Dissertations / Theses on the topic 'Agroforestry system'

This study reports the results of experiments on growth and physiology of an agricultural annual (French bean) and a young tree (poplar) in relation to limited soil water. Competition and complementarity between the species were evaluated in a model agroforestry experiment. The experiments were carried out in a greenhouse and growth cabinet with plants grown in pots containing sandy-loam compost. The species studied were Phaseolus vulgaris cv. Argus and Populus trichocarpa X P. deltoides cv. Raspalje. The main aim of the study was to characterise the responses of both species to different soil water supply regimes, shoot water supply by roots and chemical signalling from the roots in drying soil and to show how these responses could be used in the selection of suitable agroforestry for dry regions. Bean and poplar plants showed differential growth responses although both the species performed better in mixed stands than in monoculture when soil water was severely limited. Beanplants were more competitive than poplar, although both species showed complementarity in exploration for soil water. As the soil dried leaf water potential declined. Stomatal conductance of both species was more closely related to pre-dawn leaf water potential than to mid-day leaf water potential, indicating the importance of soil water status. Experiments with both vertically and horizontally divided root systems showed that bean and poplar plants with at least half of their root system in moist soil were able to maintain leaf water status as well as plants with all their root systems in moist soil. Furthermore, stomatal conductance and leaf expansion of both species were affected directly by soil drying independent of leaf water potential.

Informal agroforestry is a traditional practice in Solomon Islands, mostly intercropping food crops with fruit trees. Agroforestry systems that intercrop food crops with rows of hardwood species for the purposes of timber production have not been practiced. In response to the common problem that growers of valuable hardwood species such as teak (Tectona grandis) are reluctant to thin their trees, the Australian Centre for International Agricultural Research (ACIAR) established project FST/2007/020 to develop novel silvicultural systems to overcome this problem. Flueggea flexuosa (flueggea) is a local hardwood species that is widely utilized for housing and fencing applications. The project team established several agroforestry trials testing the hypothesis that teak and flueggea could be successfully grown together with the local tree being progressively harvested for local use, effectively thinning the plantation and allowing the teak to develop through to harvestable size. The trees could be intercropped with food crops allowing for multiple land use and income generating opportunities whilst the trees grow through to maturity. The model was based on the assumption that trees and crops, when properly managed, complement each other rather than compete in the capture and efficient use of available growth resources. This system is a hybrid of the informal agroforestry traditionally practiced in Solomon Islands and the silvicultural management techniques applied to production forestry. However, teak and flueggea have not been previously grown together under an agroforestry regime and little is known of the species interaction or of the effect of growing different food and cash crops in the interrow. Traditional practices for growing food crops in Solomon Islands begin with forest clearance and burning of debris, a slash and burn system. Mounds are made using man-made hoes or picks to give crops better growing spot away from competing weeds and surface water flow during rainy seasons. Most root crops and vegetables are planted in their own blocks and kept separate from other crops. Mixing of food crops is not a usual practice in most parts of the Solomon Islands. Other crops and trees are usually planted at the boundaries of each crop’s patch or along the boundary. Most food crops reach harvesting age after 3 months. When crops are harvested, the whole plant is uprooted, plant parts and debris are piled at a location and are burnt when dry. Where the area available for gardening area is large, the harvested plot is left to fallow but if the available area is small, crops are replanted straight after harvest, leaving no time for the soil to be replenished with nutrients through decomposition of plant materials. Amongst several silvicultural trials established in Solomon Islands, this study focuses on trials established at Ringgi and Poitete which are located at the southern and northern parts of Kolombangara Island in Western Province. These silvicultural trials were established for the purpose of examining the effect of stocking rate and species mix on teak and flueggea growth and on their potential influence over the hybrid agroforestry system. Two mixed species spacing trials and one hybrid agroforestry trial of teak and flueggea were established to test the hybrid model. The two main mixed species spacing trials have 5 treatments with 4 replicates each, treatments are a combination of stocking rate and species mix. The five different treatments include teak being grown as a monoculture (Treatment 1); and then in rows interspersed with 2 rows of flueggea at different stocking rates (Treatments 2, 3, and 4); and alternating rows of teak and flueggea at standard spacing (Treatment 5). The hybrid agroforestry trial was based on the standard 4 x 3 m spacing (Treatment 5) and further intercropped with food crops. Only Treatment 3 (4 x4m) and Treatment 4 (4 x 6m) have wider planting spaces. Standard stocking is 833 stems per hectare for Treatments 1, 2 and 5, and 625 and 416 stems per hectare for Treatments 3 and 4. This research examined the interactions occurring between teak and flueggea, and between teak, flueggea and food crops grown in the inter-row with respect to competition for nitrogen (N), light and water, resource access, changes in system interactions with the development of the canopy, nutrient loss and issues of sustainability related to harvesting of food crops, biogeochemical cycling of carbon (C) and N, root architecture and growth and yield. Total carbon (TC), total nitrogen (TN) and stable isotope δ13C and δ15N, and 15N-labelled tracer were analyzed using field sampled soil, foliage, branch, stem, root and litterfall from the stands to examine soil nutrient uptake, biomass content and cycling as a result of the intraspecific and interspecific interactions with relation to tree growth and productivity of the hybrid system over time and space. Root architecture, tree mean total height (THt) and diameter at breast height (DBH) were measured and assessed over the study period. We investigated the competition between teak and flueggea for N using a 15N-labelled tracer in a field trial in a 2 year old and a 4 year old mixed species stand. The study also reports the acquisition and allocation of TC and C isotope composition (δ13C) in different tree components of teak and flueggea. Seven pairs of trees, one of each species, were isolated using an impermeable membrane 60 cm deep and 15N-labelled tracer was applied to the soil surface. The first four plots were sampled for a period of 18 months and the age of the trees at final excavation was 4 years. The final three plots were sampled for 12 months and the age of the trees at final excavation was 2 years. Each tree was measured, felled and roots excavated, divided into the components: roots, stem, branch and foliage, and then weighed for biomass, samples of each component were oven dried at 60° C to constant weight, ground to a fine powder and analysed for TN, TC, 15N enrichment, and δ13C. There was no significant difference in component 15N enrichment between teak and flueggea at both ages, suggesting that there could be equal uptake of added 15N-labelled tracer by both species. The 15N -labelled tracer concentration was greater in the foliage followed by the root, stem and branch for teak and flueggea. However, stem had significantly greater biomass and therefore had greater 15N enrichment mass (kg) than other components of teak in the 2 years trial and with teak and flueggea at 4 years trial. Approximately 55 % of added 15N tracer was recovered in the 4 years trial and 43 % was recovered in the 2 years trial, suggesting that higher uptake is possible with well-established root structure with age. Although teak had significant growth, 15N tracer uptake and enrichment were not statistically different to those of flueggea which may mean that competition in growth resources was still at minimum stage and growth rates were species specific. TN was not significantly different between teak and flueggea components at age 2 and 4 years and may indicate equal access to available N belowground and with similar allocations. TC was not significantly different between components of teak and flueggea in either age and may indicate equal access to atmospheric C and similar allocations of photosynthates. Higher δ13C in teak components than those of flueggea indicated that teak has higher water use efficiency per kg of tree and does not discriminate against 13C as strongly as flueggea during photosynthesis. Similar 13C values in tree components within the species may be the result of subsequent partitioning of the photosynthates synthesized during photosynthesis. The litter production and C and N cycling in both teak monoculture and teak and flueggea mixed species plantings in the two trials were studied over 18 months period. Leaf litter samples were collected monthly from the five treatments. Monthly litterfall production ranged from 250.51 to 541.61 kg ha-1 depending on treatment and trial. Treatment 1 produced significantly higher total litter than Treatment 4 at Ringgi but this difference will have been due to stocking rates. When based on individual tree productivity, teak in Treatment 4 at both trials produced significantly higher litter per tree than the teak in Treatments 3, 2, 5 and 1 while there was no significant difference with flueggea productivity. Although teak and flueggea TC and TN, and δ13C and δ15N varied over the study period, their mean values were not statistically different except for teak in T4 having significantly lower values at Ringgi. Teak and flueggea C/N ratios were not statistically different at both trials except for flueggea in Treatment 2 at Ringgi which was significantly higher. The highest annual TC and TN returned to the soil from total litterfall were observed in Treatment 1 followed by Treatments 3, 5, 2 and 4 for Ringgi. The highest at Poitete was Treatment 5 followed by Treatments 1, 3, 2 and 4. When comparing each treatment and using individual tree productivity, Treatment 4 produced and returned the significantly highest litter and nutrient than Treatments 3, 2, 5 and 1. Overall, individual tree productivity demonstrated that mixed species stands have significant potential for cycling higher rates of C and N than monoculture teak stand, therefore establishment of mixed species stands especially using the stocking rates of Treatment 3 and Treatment 4 is recommended as a practical measure in forest rehabilitation and agroforestry systems to realize sustainable development of community forestry in the Solomon Islands. The spatial distribution of the root systems of teak and flueggea were examined by excavating pairs of trees of each species that had been grown in isolation plots for 2 (3 pairs) and 4 (4 pairs) years. Additional trees grown without a barrier were partly excavated to ensure that the effect of the barrier on root architecture was not significant. The root architecture of both species had similar patterns of development but showed a different topology and distribution. Teak had extensive horizontal and vertical roots and occupied a larger portion of the soil volume than flueggea. Both species had similar root biomass increment of 87 % between 2 and 4 years and roots made up 20-22 % of total tree biomass at both ages. Teak and flueggea roots occupied different depths within the soil volume, which would promote nutrient uptake efficiency and therefore minimize competition. The study evaluated the effects of stocking rate and species mix on early growth of teak in a mixed species system. Intercropping with flueggea promoted diameter, height and form of teak. Teak diameter and basal area growth significantly increased with wider planting spacing though height was not statistically different to teak in single-species stands. Intercropping with flueggea resulted in teak developing smaller branches which facilitated a self-pruning habit that promoted clear wood production. Differences in teak height between all treatments were not significant though it is interesting to note that sixty months after planting, teak in T1 at Ringgi and teak in T5 at Poitete had the greatest height as had Flueggea in T5 at Ringgi though again differences in height of flueggea was not significantly throughout the treatments. Diameter and basal area were greatest at the lower stocking than at the higher stocking for teak and flueggea. Teak of T4 had the significant diameter and basal area growth than other treatments at age 60 months. Teak form was best at the pure and mixed species stands due to self-pruning while larger crown and big branches occurred at lower stocking rates. While this can be corrected with timely silviculture, a 4 x 3 m spacing would seem to optimise the benefits of higher stocking and lower maintenance. Overall, mixed species and agroforestry systems promoted reduction and delay of competition for growth resources in the early phase of the systems compared to monocultures. Both single and mixed species systems promoted similar C and N cycling in the plantation establishment phase. Growth in basal area was significantly higher at the mixed species stands at the lowest stocking rate, which also enable longer period of intercropping of food crops. However, as the present investigation was confined to the first 5 years, which is considered as establishment phase for teak, more studies are needed as the systems mature to fully understand the systems development and interactions to maturity.
Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
School of Natural Sciences
Science, Environment, Engineering and Technology
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The spatial variation of tree growth and site factors was studied in a silvopastoral system at Glensaugh in Northeast Scotland. Sycamore (Acer pseudoplatanus L). Hybrid larch (Larix x eruolepsis Henry) and Scots pine (Pinus sylvestris L) were planted at 5 m x 5 m, 7.1 m x 7.1 m and 10 m x 10 m spacings on plots replicated over three blocks in a Randomised Complete Block design on a rye grass (Lolium perenne L) pasture which was grazed by sheep yearly from April to October. Included in the design were an agricultural control, forestry control and mowed plots. The agricultural control had no trees but grazed pasture and the mowed plots had trees but the pasture was not grazed, instead it was cut at intervals and left to decompose on site. The forestry control plots had no pasture and as such were not given fertiliser treatments and soil samples were not collected from them, in these the trees were planted at the standard 2 m x 2 m spacings and fenced off from the animals. Pastures received 160 kg N/ha^-1 annum^-1 in four equal applications. The objective of this work is to study at tree-scale the spatial variation of tree growth and site factors in grazed and ungrazed silvopastoral system plots. Total soil N, available Mg and Ca, as well as organic matter (OM), %C, pH in water and Calcium chloride increased significantly with distance from the tree while P decreased significantly with distance from the tree in grazed plots. The presence of trees or animals alone in a treatment did not significantly influence soil nutrient redistribution in a silvopastoral system. Therefore it takes the combined presence of trees and animals in a silvopastoral treatment for a significant redistribution of soil nutrients around the tree to occur.

A 3 x 2 factorial experiment was conducted to examine the outcome and some of the competitive mechanisms between P. radiata (D. Don) and pasture for N and soil moisture. The factors examined were the monthly addition of 30 kg N/ha versus no additional N, and the manipulation of the level of pasture competition by spraying and simulated-grazing to give three levels of pasture competition. The experiment coincided with a period of severe drought which greatly increased the competition for soil moisture. Removal of pasture competition by spraying released a large amount of N into the soil mineral N pool. It also reduced overall demand for N and water because of the reduction in competition resulting in improved tree growth and greater N uptake by trees. However, it was apparent that moisture was the main limiting factor for tree growth in the plus-pasture treatments because, whilst trees did take up some of the applied N in the plus-pasture treatments, they showed no increase in growth and N uptake. A localized effect of trees on pasture dry matter production and N content occurred. Directly beneath trees and in the area predominantly occupied by tree roots competition for water and N was intense. Pasture response to N was greatest away from the tree rooting zone. Pasture appeared to compete successfully due to the nature of its root system which consists of a large biomass of very fine roots compared to the small biomass of fine pine roots in the surface soil. Competition between pasture and trees was further examined using the stable isotope 15N to trace a single 15N-labelled application of N fertilizer in spring. Recovery of 15N during the split fertilizer application program was assessed by periodic pasture harvests in the simulated-grazing treatment and by obtaining a complete balance sheet after 249 days. The dynamics of plant availability of applied 15N and retention of 15N in the soil was also followed. The recovery and retention of 15NO3- and 15NH4+ in particular were compared in the simulated-grazing treatment. Larger quantities of 15NO3- remained available to plants than 15NH4+ and 15N was still found in the KCl-extractable mineral N pool at 154 and 249 days after application. P. Radiate assimilated the same amount of 15N when added as 15NO3- or 15NH4+ in the simulated-grazing treatment but uptake into the aboveground biomass of pasture was greater for 15NO3- than for 15NH4+. However, pasture uptake of 15NO3- and 15NH4+ was not significantly different when pasture stubble and roots were include in the total recovery for all harvests. Removal of pasture competition increased the availability of 15N for the period just after application but 15N uptake by P. radiata was only doubled. There were no significant differences in 15N recovery between treatments in the 0-20 cm depth of soil; on average this was 49% of that applied. Total system recovery was 107, 92, 76, and 71% for the 15NO3-treated, 15NH4+ -treated simulated-grazing treatments, 15NH4+ -treated rank, and sprayed treatments, respectively. The loss of 15N from the system was not accounted for by leaching although this was not directly measured. In the sprayed treatment where the loss of 15N was greatest, it was thought that 15N loss may have been due to denitrification. The root systems of neighbouring trees did not overlap and midway between the trees there was apparently no competition between trees and pasture since no effect of tree roots on pasture growth and 15N uptake could be shown. Uptake by artificially-grazed pasture did not seem to reduce 15N movement into the canopy to the same extent as uptake by rank pasture. In the simulated-grazing treatment the increased cycling of N or reduced pasture root growth may have provided some benefit to tree uptake of 15N.

The general goal of this research was to understand the agronomic and physiological changes of a lucerne crop in distinct physical radiation environments and to verify the potential of lucerne to grow under shaded conditions. To achieve this, the research was conducted in four main steps: (i) firstly, experimental data collection in the field using two artificial shade materials (shade cloth and wooden slats) under inigated and non-irrigated conditions; (ii) a second experiment with data collection in a typical temperate dryland agroforestry area under non-irrigated conditions; (iii) generation of a light interception sub-model suitable for shaded crops and (iv) a linkage between the light interception sub-model and a canopy photosynthesis model for agroforestry use. In experiments 1 and 2, lucerne crop was exposed to 6 different light regimes: full sunlight (FS), shade cloth (FS+CL), wooden slats (FS+SL), trees (T), trees+cloth (T +CL) and trees+slats (T+SL). The FS+SL structure produced a physical radiation environment (radiation transmission, radiation periodicity and spectral composition) that was similar to that observed in the agroforestry site (f). The mean annual photosynthetic photon flux density (PPFD) was 41 % under the FS+CL, 44% under FS+SL and 48% under T compared with FS in clear sky conditions. Plants were exposed to an intermittent (sun/shade) regime under both FS+SL and T, whereas under FS+CL the shaded light regime was continuous. The red to far-red (RIFR) ratio measured during the shade period under the slats was 0.74 and under the trees was 0.64. However, R/FR ratio increased to 1.26 and 1.23 during the illuminated period under FS+SL and T, respectively, and these were equivalent to the ratio of 1.28 observed under the FS+CL and 1.31 in FS. The radiation use efficiency (RUE) of shoots increased under the 5 shaded treatments compared with full sunlight. The pattern of radiation interception was unchanged by radiation flux, periodicity and spectral composition and all treatments had a mean extinction coefficient of 0.82. However, the magnitude of the decrease in canopy growth was less than those in PPFD transmissivity. The mean lucerne annual dry matter (DM) yield was 17.5 t ha⁻¹ in FS and 10 t ha⁻¹ under the FS+CL, FS+SL and T regimes. This declined to 3.4 t DM ha⁻¹ under T+CL (22% PPFD transmissvity) and 4.1 t DM ha⁻¹ under T+SL (23% transmissivity). A similar pattern of response was observed for leaf net photosynthesis (Pn) rates under the shade treatments compared with full sun. In addition, spectral changes observed under the trees and slats affected plant motphology by increasing the number of long stems, stem height and internode length compared with full sunlight. Thus, there were two main explanations for the increase in RUE under shade compared with full sun: (i) preferential partition of assimilates to shoot rather than root growth and/or (ii) leaves under shade were still operating at an efficient part of the photosynthetic light curve. The changes proposed for the canopy Pn model were appropriate to simulate the radiation environment of an agroforestry system. However, the model underestimated DM yields under the continuous and intermittent shade regimes. These were considered to be mainly associated with plant factors, such as overestimation in maintenance respiration and partitioning between shoots and roots in shade and the intermittency light effect on leaf Pn rates. Further investigation in these topics must be addressed to accurately predict crop yield in agroforestry areas. Overall, the lucerne crop responded typically as a sun-adapted plant under shade. It was concluded that lucerne yield potential to grow under intermediate shade was superior to most of C3 pastures previously promoted in the literature.

1. This research project on small mammals was carried out between December 1994 and August 1997 at the Leeds University Farms in West Yorkshire. 2. Densities of captures were assessed using weekly live trapping and mark- release-recapture (MRR) methods. One hundred and thirty two Longworth traps were set out in a complex fanning landscape consisting of four replicate blocks of silvoarable agroforestry designed as a series of tree rows planted at low density (178 trees/ha) and separated by arable alleys cropped with cereals (wheat or barley). Adjacent to each of these agroforestry systems is an area of trees planted at forestry density (2500 trees/ha), an arable field and a mature hedgerow. 3. Overall 1680 captures were obtained, 70% of which were of Apodemus sylvaticus, 20 % of Sorex araneus and only 10% of Clethrionomys glareolus. 4. A. sylvaticus and S. araneus showed preferences for the agroforestry system, whereas C. glareolus prefered the mature hedgerows. Overall, the highest density of capture was found in the tree rows (13.4 animals per 100 trap nights) and the least in the arable field (4.2 animals per 100 trap nights) 5. Densities of captures of A. sylvaticus were greater in Autumn than the other seasons, notably in the tree rows when the arable areas provide little cover. 6. Population densities were calculated and showed the same seasonal pattern as densities of captures. The highest population density was in October 1996 (36 mice/ha). 7. Male A. sylvaticus bred extensively from mid-Winter until early Summer. The female had a longer and more sporadic breeding period. Overall, the animals showed little or no breeding condition during the phase of population increase in the Autumn-Winter period. 8. Radiotracking of A. sylvaticus was carried out from May 1996 until June 1997. Home ranges were estimated using cluster analysis. 9. Home range sizes of A. sylvaticus, estimated using 95% of the density distribution, were between 0.04 and 0.30 ha. Home ranges of males were larger than those of females and showed seasonal patterns, with larger ranges during the Spring-Summer period which corresponds to the breeding season. 10. All the individuals tracked had overlapping home ranges spreading over the different habitats, particularly in the agroforestry system (tree rows and arable alleys) where most of the activity of the animals was recorded throughout the year.

Zea mays L. is an important food crop and common intercrop species grown in semi-arid agroforestry systems in Kenya, East Africa. A preliminary field study showed that AMF spores occurred in particularly high number in this system compared with that reported for other less disturbed ecosystems. The same spore types occurred in tree and alley soil, however spore number and composition were variable, between host species, in fallow and cropped areas of the system and between wet and dry seasons. At the end of the dry season (February, 1991), fallow areas had significantly higher spore numbers than cropped areas of the system. Lower numbers of spores were found in soil in the dry season than in the wet season, when spore numbers were significantly higher in tree soil in the cropped area than in soil from other areas. The first experiment was established to determine the influence of host and fallowing on the effectiveness of AMF populations occurring in this system on mycorrhizal formation, growth and nutrition of plants. These results showed that plants inoculated with tree soil from the cropped area of the system had significantly higher mycorrhizal infection formation in roots, however this was not reflected in the growth and nutrient uptake of plants which were unaffected by AMF inoculation. The effects of soil type, soil volume and soil phosphorus were thought to have influenced the response of plants to inoculation in the previous experiment and so the influence of these factors on growth and nutrition of inoculated and uninoculated plants were investigated. Results from this experiment showed that plants had significantly different mycorrhizal infection in roots when grown in different soils. Mycorrhizal infection was higher in plants grown in smaller pots, decreasing significantly with incremental increases (1, 4 and 10 litre pots) in soil volume.

Mestrado Mediterranean Forestry and Natural Resources Management (MEDFOR) - Instituto Superior de Agronomia - UL
Ethiopia economy strongly depends on coffee (Coffea arabica L.) production. Coffee, like many other agricultural crops, is sensitive to climate change. Future changes in climate will have a negative impact on coffee yield and quality. Studies have called for an urgent development of coffee’s adaptation strategies against climate change and agroforestry systems have received attention as an adaptation and mitigation strategy for coffee production under future climate. This study contributes to the assessment of coffee production in 1) monoculture and in 2) agroforestry systems, under different climate scenarios, in four different regions, providing insights for preliminary recommendations for coffee growers and policy makers. The Yield-SAFE processbased model was used to predict yield of coffee in monoculture and under agroforestry systems for forty years of current and future climate (Representative Concentration Pathways (RCP) 4.5 and 8.5 - HadCM2 model). In monoculture system, coffee yield was estimated to decrease between 4-38 % and 16-58 % in RCP 4.5 and 8.5, respectively from its current yield of 1000-1600 kg ha-1 yr-1. However, in agroforestry system the decrease was between 4-13 % and 13-25 % in RCP 4.5 and 8.5, respectively from its current yield of 1200-2200 kg ha-1 yr-1, showing that agroforestry systems have a higher resilience when facing future climate change.
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Sistemas agroflorestais abrigam grande biodiversidade quando comparados a outros usos da terra e representam uma ferramenta importante para conciliar produção agrícola e conservação de recursos naturais em paisagens modificadas pelo homem. Esta tese é composta de três capítulos que sintetizam e ampliam o conhecimento a respeito da influência do manejo das agroflorestas e da cobertura florestal remanescente sobre a distribuição dos organismos e apontam ações visando a conservação de biodiversidade em mosaicos agroflorestais. No primeiro capítulo revisamos a informação científica publicada até 2008 sobre a diversidade da fauna e flora nativas nas agroflorestas de cacau do sul da Bahia. Com base nesta síntese, identificamos recursos chave presentes nessas plantações que se relacionam com a maior riqueza de espécies ou presença de táxons ameaçados e evidenciamos a importância da manutenção de florestas nativas em mosaicos agroflorestais. Finalizamos esta revisão com recomendações para um manejo adaptativo visando a conservação de biodiversidade em propriedades e mosaicos agroflorestais e levantamos questões para serem respondidas por estudos futuros. Nos capítulos 2 e 3, apresentamos dois estudos empíricos realizados a partir da amostragem de mamíferos por armadilhas fotográficas em 30 agroflorestas e remanescentes florestais adjacentes a nove delas. No segundo capítulo, construímos e testamos hipóteses que descrevem quais espécies de mamífero de maior porte com ocorrência na região devem ser positiva e negativamente influenciadas pela conversão de florestas em agroflorestas e como estas respostas diferenciais deveriam se refletir na estrutura, composição e diversidade das assembléias. O valor de conservação das agroflorestas é apoiado pela presença de espécies endêmicas ou ameaças de extinção e pela composição de espécies similar entre florestas e agroflorestas. Entretanto, ao identificar que espécies caçadas e mortas por retaliação são raras ou ausentes na nossa amostragem e que agroflorestas são menos usadas por espécies arborícolas e mais usadas por espécies exóticas do que as florestas, nós explicitamos porque o valor de conservação das agroflorestas deve ser visto com cuidado, destacando questões que podem contribuir para a viabilidade das populações de mamíferos de maior porte em paisagens agroflorestais. No terceiro capítulo, contrastamos a importância relativa da intensificação do manejo e da cobertura florestal do entorno sobre o uso das agroflorestas de cacau por mamíferos de maior porte. Nossos resultados indicam que, na paisagem de estudo, fatores diretamente e indiretamente relacionados à intensificação do manejo das agroflorestas são mais importantes para a distribuição das espécies de mamíferos do que a quantidade de florestas remanescentes no entorno. A taxa de registro de cães domésticos (fator indireto) teve efeito negativo sobre várias espécies de mamíferos, enquanto a redução da conectividade do dossel das agroflorestas (diretamente associada ao manejo do sombreamento) teve um efeito negativo sobre espécies arborícolas e a redução da altura do estrato herbáceo (diretamente associada à freqüência de roçagem) um efeito positivo pequeno sobre espécies generalistas. Por outro lado, nesse mosaico agroflorestal com grande quantidade de florestas nativas remanescentes, apenas as espécies generalistas responderam à variação da quantidade de florestas no entorno, sendo mais comuns em agroflorestas circundadas por menor quantidade de floresta. Assim, em mosaicos agroflorestais com elevada cobertura florestal, restringir os efeitos negativos decorrentes da intensificação do uso da terra, como o controle das populações de cães domésticos e das atividades de caça e o planejamento cuidadoso do sombreamento das agroflorestas, deve resultar em maiores benefícios para o uso das agroflorestas por mamíferos de maior porte do que alterações na configuração espacial dos remanescentes florestais. Entretanto, a importância da cobertura florestal em relação a intensificação do manejo deve aumentar em paisagens mais desmatadas. Em conjunto, os três capítulos desta tese mostram que o conhecimento científico atual pode embasar o desenho de práticas e políticas públicas para conciliar produção agrícola e conservação em mosaicos agroflorestais. Tais práticas devem ser continuamente avaliadas, contribuindo e sendo repensadas com o avanço do conhecimento científico
Agroforestry systems harbor high levels of biodiversity if contrasted to other land uses and represent an important tool to reconcile agricultural production and conservation in humanmodified landscapes. This thesis is composed of three chapters that synthesize and expand the knowledge on the influence of agroforest management and remaining forest cover on the distribution of organisms, and highlight practices aiming biodiversity conservation in agroflorestry mosaics. In the first chapter we review the scientific information published until 2008 on the diversity of native fauna and flora in cacao agroforests in southern Bahia. Based on this synthesis, we identify key agroforest resources associated with higher species richness or the presence of threatened taxa, and emphasize the importance of Forest cover maintenance in agroforestry mosaics. We end this review with recommendations to an adaptive management aiming biodiversity conservation on farms and agroforestry mosaics and consider issues to be developed by future studies. On chapters 2 and 3 we present two empirical studies based on photographic records of large mammals in 30 agroforests and forest remnants adjacent to nine of them. In the second chapter we constructed and tested hypotheses describing which mammals from the regional species pool should be positively and negatively influenced by the conversion of forest to agroforests and how these differential responses should change assemblage structure, composition, and diversity. The high conservation value of agroforests is supported by the presence of species of conservation concern, and a similar species composition between forests and agroforests. However, by identifying that hunted and persecuted species are rare or absent in our samples, and that agroforests are less used by arboreal species and more used by non-native species than forest, we explicit why the conservation value of agroforests should be viewed with caution and underline issues that should be addressed to improve the viability of large mammal populations in agroforestry mosaics. In the third chapter we contrast the relative importance of management intensification and surrounding forest cover for the use of agroforests by large mammals. Our results indicate that, in the studied landscape, factors directly and indirectly related to management intensification are more important to define large mammal distribution than the amount and spatial arrangement of surrounding forest cover. High domestic dog capture rate (an indirect factor) had a negative effect on several species, while low canopy connectivity (directly associated to shade management) was negative correlated to the distribution of arboreal species and lower herbaceous vegetation (directly associated to ground vegetation clearance) had a minor positive influence on generalist species. On the other hand, in this agroforestry mosaic highly covered by native forests, only generalist species responded (positively) to the decrease in surrounding forest cover. In agroforestry mosaics from highly forested regions, restricting the negative effects of land-use intensification, such as the control of domestic dog populations and overhunting, and the careful planning of shade management, is likely to bring greater benefit to large mammal use of agroforests than the spatial arrangement of forest remnants. However, the importance of forest cover relative to management intensification is likely to be higher as deforestation increases. The three chapters show that current scientific knowledge can already support policy and management practices to conciliate agricultural production and biodiversity conservation in agroforestry mosaics. Such practices should be continuously evaluated, contributing to and being supported by improvement of scientific knowledge

Face aux besoins croissants pour une production agricole durable, les systems de culture évoluent vers des systèmes qui accomplissent des objectifs environnementaux et agricoles multiples. La recherche en conception de systèmes de cultures (CSC) s'intéresse à l'effet des pratiques et de l'environnement sur les systèmes de culture et leur performance. L'interaction entre production et services ecosystémiques, et la quantification de ces relations, sont un aspect clé de ce domaine de recherche. Une variété d'approches ont été théorisées, tels que l'utilisation de modèles et la mobilisation de connaissances expertes. Les modèles permettent de tester rapidement et à faible coût l'effet de pratiques agricoles dans une variété de conditions, mais l'application de conclusions théoriques à la parcelle peut être limitée par des contraintes locales ainsi que des obstacles à la communication chercheur-agriculteur. Mobiliser les agriculteurs et autres acteurs pertinents pour la CSC peut aider à surmonter ces obstacles ; cependant, cela limite l'innovation au cadre des connaissances expertes.L'objectif de cette thèse est de combiner la modélisation et des méthodes participatives pour une méthode de CSC qui exploite le potentiel de la modélisation numérique tout en s'assurant que les solutions proposées prennent en compte les contraintes environnementales et socioéconomiques. Après avoir revu l'état d'avancement de la recherche en prototypage et en CSC, nous proposons un cadre méthodologique divisé en quatre parties ; a) combiner une typologie des pratiques et un modèle conceptuel pour évaluer la diversité des pratiques, contraintes et trade-offs dans une zone de production ; b) acquérir des données de terrain pour quantifier les trade-offs pertinents entre production et services écosystémiques ; c) sélectionner et préparer un modèle numérique approprié pour simuler les effets des pratiques sur la production et l'apport de services ; et d) évaluer si l'interaction d'agriculteurs avec le modèle numérique peut générer des systèmes de culture potentiels qui répondraient aux objectifs agro-environnementaux posées (apport d'un service écosystémique) ainsi qu'être acceptables pour les agriculteurs qui les adapteraient à l'expérimentation dans leurs parcelles.The systèmes agroforestiers à base de café (cafés/arbres d'ombrage) du Costa Rica central ont étés le système de culture choisi pour répondre à ces questions. Les systèmes agroforestiers offrent de nombreuses occasions d'étudier et évaluer les services écosystémiques apportés, en plus de la production principale. L'association de deux cultures pérennes place l'évaluation de la performance à long terme et de la durabilité des systèmes au centre de la question. La culture du café au Costa Rica fait vivre une part importante de la population, et est aussi basée sur la gestion intensive d'une culture à haute valeur d'exportation, vulnérable aux fluctuations des prix sur le marché mondial ainsi qu'au changements climatiques. Des pentes raides et une saison des pluies importante créent des problèmes d'érosion significatifs ; cependant, certaines pratiques de contrôle de l'érosion (utilisation d'arbres d'ombrage et d'adventices) impactent la production de café. La réconciliation de ces deux aspects nous offrent l'occasion de tester notre cadre méthodologique dans une situation où une solide argumentation technique serait nécessaire pour encourager les expérimentations dans les parcelles. Enfin, le dernier chapitre porte une réflexion d'ensemble sur l'importance de choisir et préparer correctement un modèle agronomomique adéquat, les application potentielles de cette méthodologie, ainsi que les recommandations que nous avons pu effectuer en termes de pratiques de contrôle de l'érosion dans la zone d'étude
In the face of increasing concerns about sustainability of agricultural production, cropping systemsare evolving towards systems that fulfill multiple agronomic and environmental objectives. Researchin cropping systems design (CSD) is concerned with studying the effect of farming practices oncropping systems and their performance. The interaction between production and ecosystemservices, and quantification of trade-offs between the two, is a key aspect of this research. A varietyof approaches have been theorized, such as use of models and mobilization of expert knowledge.Models allows fast and low-cost testing of the effect of farming practices under a variety ofconditions, but the application of theoretical outcomes to on-farm changes can be limited by localconstraints and researcher-farmer communication. Mobilizing farmers and other relevantstakeholders for CSD can help overcome these obstacles; however this limits innovation to the scopeof expert knowledge.The objective of this thesis is to combine modeling and participatory methods for a CSD frameworkthat harnesses the potential of numerical modeling while ensuring the proposed solutions take intoaccount socioeconomic and environmental constraints. After an overview of current advances inprototyping and CSD, we propose an methodological framework divided into four parts; a) combininga typology of farming practices and a conceptual model to appraise the diversity of farming practices,constraints and trade-offs at the plot scale in a defined production area; b) collection of field data forquantifying relevant trade-offs between production and ecosystem services; c) selecting andpreparing an appropriate numerical model for simulating the effects of farming practices onproduction and provision of ecosystem services; and d) evaluating whether the interaction of farmerswith a numerical model can generate candidate cropping systems that fulfill our agro-environmentalobjectives (provision of ecosystem service) as well as being suitable for the farmers who will adaptthem for on-farm experimentation.The coffee-based agroforestry systems (coffee/shade trees) of central Costa Rica were the chosenproduction system for answering these questions. Agroforestry systems offer plentiful opportunitiesfor valuing ecosystem services in addition to crop production; the combination of two perennialcrops brings long-term performance assessment and sustainability of the system to the heart of thequestion. Coffee cultivation in central Costa Rica concerns a large amount of livelihoods, but is alsobased on intensive management of a highly valued cash crop vulnerable to price fluctuations on theglobal market as well as climate change. Steep slopes and heavy rainfall also cause high levels of soilerosion; yet certain indirect erosion control practices (such as the use of shade trees of weeds) alsohave an impact on coffee production. The reconciliation of these two aspects offers the opportunityto test our methodological framework in situations where precise discussions onproduction/environment trade-offs are needed.Finally, in the last chapter we reflect on the importance of correctly choosing and preparing the rightmodel for the job, potential application of this methodology, as well as the recommendations wereable to make in terms of erosion control practices in the study area

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The rural area of the municipality of Pedreira presents its fragmented landscape caused by agricultural expansion occurred in the region at the time of deploying cafezais and then pastures. Thus a proposal for agroforestry systems with potential beekeeping presents itself as a highly recommended strategy in the recovery of degraded areas coupled with the increase of income through beekeeping addition to environmental services generated by the activity. The general objectve of this study was to draw up designs for groforestry purposes with bee and analyze the specific objective ethnobotanical knowledge of farmers and beekeepers on local conditions, as a starting point for implementation and execution of plans for recovery of degraded areas, with focus in Areas of Protection Permanent and Legal Reserve. The proposal agroforestry systems with potential beekeeping are likely to be implemented considering the multifunctional to serve, from the legal aspects, ecological, economic and social.
A zona rural do município de Pedreira apresenta sua paisagem fragmentada causada pela expansão agrícola ocorrida na região na época da implantação de cafezais e posteriormente pastagens. Assim sendo uma proposta de sistemas agroflorestais com potencial apícola apresenta-se como uma estratégia altamente recomendável na recuperação de áreas degradadas aliada ao aumento de renda através da apicultura além dos serviços ambientais gerados pela atividade. O objetivo geral desse trabalho foi a elaboração de desenhos de sistemas agroflorestais com finalidades apícolas e o objetivo específico analisar o conhecimento etnobotânico dos agricultores e apicultores sobre as condições locais, como ponto de partida para implementação e execução de planos de recuperação de áreas degradadas, com enfoque à proteção de Áreas de Preservação Permanente e Reserva Legal. A proposta sistemas agroflorestais com potencial apícola são passíveis de serem executadas considerando a multifuncionalidade a que servem, desde os aspectos legais, ecológicos, econômicos e sociais.

O experimento foi estabelecido para testar e avaliar os diferentes sistemas agroflorestais na região de Manaus, quanto à dinâmica do crescimento dos componentes arbóreos e às características físicas do solo, em uma área que foi desmatada e posteriormente estabelecido uma pastagem. O desenho experimental foi de blocos ao acaso com 5 tratamentos, 3 repetições, em parcelas de 50 x 60 m. Os 4 sistemas foram específicos para recuperação de pastagem, sendo Agrossilvipastoril Altos Insumos (ASP1), Agrossilvipastoril Baixos Insumos (ASP2) Agrossilvicultural (ASC1) e Agrossilvicultural multi-estrato (ASC2). No ASP1, foram aplicado a Calagem e P, N, K, nos demais apenas adubação de P. Os sistemas ASP1 e ASP2 foram baseados em árvores, ASC1 com base em palmeiras e ASC2 com maior diversidade es espécies. Em todos os tratamentos foram plantadas culturas anuais durante a fase de crescimento das espécies arbóreas. No ASC1, a pupunha produziu pouca liteira, a Colubrina apresentou características que são desejáveis ao sistema agroflorestal, como o crescimento do fuste reto e boa qualidade de madeira. No ASC2 o cupuaçu teve sua produtividade elevada, devido a incorporação de folhas e galhos de ingá na fase de pr-e-floração. A castanha do Pará, o mogno e genipapo tiveram um bom desenvolvimento. O cultivo do mogno combinado com outras espécies florestais, com características semelhantes à do ingá, tais como rápido crescimento e produção de biomassa, apresentou menor percentagem de ataque (27%) do inseto Hypsipyla grandella Zeller, na fase inicial, com ataques superior a 8 m de altura da planta, o que tornaria possível ofertar madeira serrada maior que 6 m de comprimento. Os resultados do tratamento ASP1 indicam melhor disponibilidade de água no solo, devido principalmente este tratamento ser manejado com gramíneas, leguminosas de cobertura como desmodium e leguminosas arbóreas como Paricá e Ingá, responsáveis pela descompactação ) do solo durante a recuperação do pasto.
The experiment was established to test and evaluate the different agroforestry systems in the region of the City of Manaus (Central Brazilian Amazonia). A test aimed at the dynamics of growth of the arboreal components and soil physical characteristics, within an area that has been deforested and subsequently turned into pasture land. The experimental design was undertaken in random blocks with 5 treatments, 3 repetitions, in parcels of 50 x 60 m. The 4 systems were specific to recovery of pasture, which were: Agrosilvopastoral High Inputs (ASP1) and Agrosilvocultural Low Inputs (ASP2), Agrosilvocultural (ASC1) and Agrosilvocultural multi-strata (ASC2). In ASP1 were applied liming and P, N, K, and the remaining only phosphorous (P). The systems ASP1 and ASP2 were based on trees; ASP1 based on palm species and ASC2 with greater diversity of species. In all treatments were planted annual crops during growth phase of the arboreal species. In the ASC1, the pupunha tree produces small quantities of litter, the Colubrina presented characteristics that are desirable to the agroforestry system, such as upright growth and good wood quality. In the ASC2, the cupuaçu increased its production, given the incorporation of Ieaves and branches of the Inga plant in the pre-flowering phase. Brazil-Nut, Mahogany and Genipapo had all good development. The cultivation of Mahogany associated with other forestry species, with similar characteristics to the Inga plant, such as fast growth and high biomass production, presented smaller of insect attack (27%) Hypsipyla grandella Zeller, in the initial phase, with attacks greater occurring at heights greater then 8 m on the plant, which would allow for the possibility of sale of Iumbered wood with 6 m of Iength. Results of treatment ASP1 indicate better availability of water in soil, mainly due to this treatment be under grasses covered soil (grass land), cover crop such leguminous desmodium and arboreal leguminous trees such as Parica and Inga, wbich are responsible for the de-compactation of soil during the process of pasture recovery.

Nos últimos 20 anos os sistemas Agroflorestais vem fazendo parte de uma proposta alternativa de produção agropecuária, em especial para agricultura familiar, porque esse modelo de produção favorece e contribui para uma produção com sustentabilidade ambiental devido suas formas de manejos. Assim o objetivo desse trabalho é demonstrar a viabilidade desse sistema de produção dentro e fora da Reserva Legal na região do Apiaú, Município de Mucajaí, Roraima, Brasil. Para tanto utilizamos como materiais e métodos visita a campo, entrevistas e observações no local de estudo, os quais foram compilados e transformados em avaliações socioeconômicas e avaliação de viabilidade econômica do SAF. Observou-se que o local de estudo tem baixa demografia, resultado de condições adversas à sobrevivência no local, seja pela falta de políticas públicas, infraestrutura, incentivo financeiro, ou por despreparo do trato com a terra por parte dos agricultores rurais e falta de tecnológica capaz de mantê-los em condições de produção proporcional com equidade ao sistema patronal. Assim, o estudo realizado propôs-se a demonstrar como alternativa de produção ao pequeno produtor, o uso do SAF em área de Reserva Legal, e o resultado obtido com as pesquisas indicam que o SAF constitui-se como uma alternativa viável, em virtude de sua capacidade de melhor aproveitamento dos recursos naturais na produção agropecuária, reduzindo ao mínimo o uso de insumos não renováveis, conservando o meio ambiente, gerando renda e ganho socioeconômico da população local.
Over the past 20 years, the agroforestry systems has been part of an alternative proposal for agriculture production, especially for family farms, because this production model favors and contributes to a production with environmental sustainability because their forms of managements. Thus the aim of this study is demonstrate the feasibility of this system of production within and outside the Reserva Legal inside the Apiaú city, Mucajaí city, Roraima, Brasil. For both we used like material and field methods, questionnaires, interviews and observations holistic. Witch were compiled and transformed into socioeconomic assessments of economic feasibility assessment of the SAF. Thus it was found that the study site there is low demographic, result of adverse conditions of survival on the local, is the lack of public policies, infrastructure, financial incentive, lack of preparation to deal with the land by the rural farmers and technology diffusion capable to keep them in production conditions with equity to patronal system. So is in this sense that had the intention to demonstrate how production alternative to small farmer in the area of legal reserve through the SAF may be an option of quantitative and qualitative, by virtue of its ability to better use natural resources in agricultural production while minimizing the use of non-renewable inputs and conserving the environment, generating income and gain socioeconomic local population.

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Agriculture is one of the activities that has impacted the environment more current day; Producing food in ways that reduce the impact of nature is a challenge to be overcome. The agroforestry system is an alternative of agricultural production associated to the cultivation of trees that reduce the devastation of nature. Through this research, possibilities of minimizing environmental impacts in agriculture were studied, based on the use of mathematical knowledge. This research has a qualitative approach, initially consisted of the application of questionnaires with open and closed questions to ten teachers and twenty students of a Technical Course in Agropecu?ria Integrated to High School in Par? Federal Institute of Education, Science and Technology, Marab? Rural Campus. During the development of the research several educational practices were carried out; In these activities, the students participated actively and in the end the action and its importance in the agricultural context was reassessed, always trying to enable those involved to perceive the importance of the knowledge built in the school in the daily activities. The objective was to investigate the view of both regarding the importance of educational practices developed in the agricultural context and the use of mathematical knowledge to reduce the damage caused to nature, particularly the agroforestry system. The results point to the importance of mathematics contents, articulated with the other areas of the curriculum, in the search for alternatives that reduce the environmental impacts on agricultural activity.
A agricultura ? uma das atividades que mais tem impactado o meio ambiente nos dias atuais. Produzir alimentos de forma que reduza o impacto causado a natureza ? um desafio a ser superado. O sistema agroflorestal, ? uma alternativa de produ??o agr?cola associada ao cultivo de ?rvores que reduzem a devasta??o da natureza. Atrav?s desta pesquisa, foram estudadas possibilidades de minimizar os impactos ambientais na agricultura, a partir do uso do conhecimento matem?tico. Esta pesquisa tem abordagem qualitativa, consistiu inicialmente na aplica??o de question?rios com perguntas abertas e fechadas a dez docentes e vinte discentes de um Curso T?cnico em Agropecu?ria Integrado ao Ensino M?dio do Instituto Federal de Educa??o, Ci?ncia e tecnologia do Par?, Campus Rural de Marab?. Durante o desenvolvimento da pesquisa v?rias pr?ticas educativas foram realizadas; nessas atividades os estudantes participavam ativamente e ao final foi reavaliada a a??o e a sua import?ncia no contexto agr?cola, procurando sempre possibilitar que os envolvidos percebessem a import?ncia dos conhecimentos constru?dos na escola nos afazeres do cotidiano. O objetivo foi investigar a vis?o de ambos em rela??o a import?ncia de pr?ticas educativas, desenvolvidas no contexto agr?cola, e o uso dos conhecimentos matem?ticos para a redu??o dos danos causados ? natureza, em particular ao sistema agroflorestal. Os resultados apontam para a import?ncia dos conte?dos de matem?tica, articulado com as demais ?reas do curr?culo, na busca de alternativas que reduzam os impactos ambientais na atividade agr?cola.

Rural people in the Sahel derive multiple benefits from local ecosystem services on a daily basis. At the same time, a large proportion of the population lives in multidimensional poverty. The global sustainability challenge is thus manifested in its one extreme here, with a strong need to improve human well-being without degrading the landscapes that people depend on. To address this challenge, knowledge on how local people interact with their landscapes, and how this changes over time, must be improved. An ecosystem services approach, focusing on benefits to people from ecosystem processes, is useful in this context. However, methods for assessing ecosystem services that include local knowledge while addressing a scale relevant for development interventions are lacking. In this thesis, such methods are developed to study Sahelian landscapes through an ecosystem services lens. The thesis is focused on village landscapes and is based on in-depth fieldwork in six villages in northern Burkina Faso. In these villages, participatory methods were used to identify social-ecological patches (landscape units that correspond with local descriptions of landscapes, characterized by a combination of land use, land cover and topography), the provisioning ecosystem services generated in each social-ecological patch, and the benefits from ecosystem services to livelihoods (Paper I). In Paper II, change in cover of social-ecological patches mapped on aerial photographs and satellite images from the period 1952-2016 was combined with population data and focus group discussions to evaluate change in generation of ecosystem services over time. In Paper III, up-scaling of the village scale assessment to provincial scale was done through the development of a classification method to identify social-ecological patches on medium-resolution satellite images. Paper IV addresses the whole Sudano-Sahelian climate zone of West Africa, to analyze woody vegetation as a key component for ecosystem services generation in the landscape. It is based on a systematic review of which provisioning and regulating ecosystem services are documented from trees and shrubs on agricultural lands in the region. Social-ecological patches and associated sets of ecosystem services are very similar in all studied villages across the two regions. Most social-ecological patches generate multiple ecosystem services with multiple benefits, illustrating a multifunctional landscape (Paper I). The social-ecological patches and ecosystem services are confirmed at province level in both regions, and the dominant social-ecological patches can be mapped with high accuracy on medium-resolution satellite images (Paper III). The potential generation of cultivated crops has more or less kept up with population growth in the villages, while the potential for other ecosystem services, particularly firewood, has decreased per capita (Paper II). Trees and shrubs contribute with multiple ecosystem services, but their landscape effects, especially on regulating ecosystem services, must be better studied (Paper IV). The thesis provides new insights about the complex and multi-functional landscapes of rural Sahel, nuancing dominating narratives on environmental change in the region. It also provides new methods that include local knowledge in ecosystem services assessments, which can be up-scaled to scales relevant for development interventions, and used to analyze changes in ecosystem services over time.

At the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 2: Manuscript. Paper 3: Manuscript.

 

A radiação fotossinteticamente ativa (RFA) é uma das variáveis mais importantes para o crescimento e desenvolvimento de plantas, estejam elas localizadas, na terra, abaixo da água ou no espaço sideral. Quando se trata de sistemas agroflorestais a RFA é uma das variáveis mais importantes, por isso nesses sistemas existe a necessidade de criar na floresta as melhores condições para o desenvolvimento das culturas abaixo desta. Condições essas dependentes da escolha da espécie, do espaçamento e dos manejos silviculturais, refletindo diretamente na radiação disponível abaixo da floresta. Em pequenas propriedades rurais o eucalipto vêm sendo utilizado como um cultivo secundário à agricultura e por se tratar de uma cultura de longo prazo o cultivo do eucalipto enfrenta dificuldades em sua permanência nessas pequenas propriedades. Uma das alternativas é o seu uso em sistemas agroflorestais, de forma que se mantenha a produção agrícola e ao mesmo tempo a floresta de eucalipto. Este trabalho teve como objetivo estudar diferentes situações de plantios de eucalipto já estabelecidos e sua relação com a RFA, e através dela obter para os eucaliptos a Taxa de interceptação (TI) e Indice de área foliar (IAF) pela Lei de Lambert-Beer. Neste trabalho foram avaliados plantios de eucalipto tendo como variáveis: espécies e as práticas de manejo de desrama e desbaste contemplando os seguintes experimentos e resultados: Avaliação de fileira dupla isolada com espaçamento 3 x 2 m, com E. urophylla x E. grandis com 24 meses de idade (Piracicaba-SP) em que fileiras duplas apresentaram de condições RFA razoáveis nas entrelinhas (200 e 799 μmol m- 2 s-1) e ideal nas linhas (maior que 800 μmol m- 2 s-1) para o desenvolvimento de plantas nas entrelinhas e melhor nas linhas; Comparativo entre espécies de eucalipto com 60 meses de idade e espaçamento 3 x 2 m (Piracicaba-SP) em que nas entrelinhas as espécies E. camaldulensis, E. robusta, E. grandis, IPEF 137, E. urophylla x E. grandis, E. urophylla e E. saligna e nas as linhas E. camaldulensis, E. robusta, E. grandis, E. urophylla x E. grandis e E. saligna apresentaram condições razoáveis de RFA para o desenvolvimento de plantas; Comparativo entre antes e depois da desrama em 7 espécies de eucalipto com 12 meses de idade e espaçamento 3 x 2 m (Piracicaba-SP) onde houve aumento da RFA depois da desrama na maioria dos casos, antes da desrama nas entrelinhas apenas as espécies H15 e E. grandis apresentaram condições razoáveis de RFA para o desenvolvimento de plantas, depois da desrama as espécies H15, I144 e E. grandis, E. urophylla e E. citriodora apresentaram essas condições, nas linhas antes da desrama nenhuma das espécies apresentaram condições razoáveis de RFA, depois da desrama as espécies I144, H13, E. urophylla e E. citriodora apresentaram condições razoáveis de RFA para o desenvolvimento de plantas; Comparativo entre três intensidades de desbaste, 55%, 70% e 85%, em eucalipto E. grandis com 228 meses de idade e espaçamento original 3 x 2 m (Itatinga-SP) em que todas as intensidades apresentaram condições razoáveis de RFA para o desenvolvimento de plantas, sendo os melhores resultados obtidos nas linhas e entrelinhas da intensidade de 70%; Comparativo entre 24 espécies de eucalipto com 12 meses de idade e espaçamento 3 x 2 m (Anhembi-SP) cujos resultados nas entrelinhas as espécies E. citriodora, E. pilularis, E. phaeothrica, E. microcorys, E. deglupta, E. paniculata, E. tereticornis, E. exserta, E. saligna, E. botryoides, E. grandis, E. urophylla, E. urophylla x E. grandis, E. pellita, E. propinqua, E. resinifera, E. dunni, E. robusta e E. camaldulensis apresentaram condições razoáveis de RFA e as espécies E. maculata, E.torelliodora e E. cloeziana apresentaram condições ideais de RFA para o desenvolvimento de plantas, nas linhas as espécies E. citriodora, E. pilularis, E. phaeothrica, E. microcorys, E. deglupta, E. paniculata, E. tereticornis, E. exserta, E. saligna, E. grandis, E. urophylla, E. urophylla x E. grandis, E. pellita, E. propinqua, E. resinifera, E. dunni, E. robusta e E. cloeziana apresentaram condições razoáveis de RFA e as espécies E. maculata, E. torelliodora apresentaram condições ideais de RFA para o desenvolvimento de plantas. Conclui-se com esse trabalho que as espécies E. camaldulensis, E. robusta, E. grandis, E. urophylla x E. grandis e E. saligna apresentaram condições razoáveis de RFA tanto aos 12 meses como aos 60 meses, porém, somente as espécies E. maculata, E. torelliodora e E. cloeziana com 12 meses apresentaram condições ideais de RFA; o desbaste teve efeito positivo no aumento da RFA com as intensidades de 70% e 85% em comparação com a de 55%; plantios de eucalipto em fileira dupla solitária permitem que a RFA seja transmitida pela copa das árvores com maior facilidade nas linhas e menor nas entrelinhas, ambas são favorecidas por não haverem fileiras de árvores em um dos lados. O cálculo do IAF pela Lei de Lambert-Beer permite a identificação dessa importante variável de forma rápida e não destrutiva. A utilização da Lei de Lambert-Beer na maioria dos casos estudados apresentou como resultado valores dentro do específico para o eucalipto 2 a 4,5 m2 m-2 (Foelkel, 2005).
The photosynthetically active radiation (PAR) is one of the most important variables for the growth and development of plants, whether they are located on the earth, under water or in outer space. When it comes to agroforestry systems PAR is one of the most important variables, so in these systems there is a need to create in the forest the best conditions for the development of the crops below it. These conditions depend on species selection, spacing and silvicultural management, directly reflecting the available radiation below the forest. In small farmers, eucalyptus has been used as a crop secondary to agriculture and because it is a long-term crop, eucalyptus cultivation faces difficulties in its permanence in these small farmers. One of the alternatives is its use in agroforestry systems, so as to maintain agricultural production and at the same time the eucalyptus forest. The objective of this work was to study different situations of eucalyptus plantations already established and their relationship with PAR, and through it to obtain for eucalyptus the Intercept Rate (IR) and Foliar Area Index (LAI) by Lambert-Beer Law. In this work, eucalyptus plantations were evaluated, with species variables and the practices of weed management and thinning, the following experiments and results were: Evaluation of an isolated double row with 3 x 2 m spacing with E. urophylla x E. grandis 24 months of age (Piracicaba-SP) in which double rows presented reasonable RFA conditions between the lines (200 and 799 μmol m-2 s-1) and ideal in the lines (greater than 800 μmol m-2 s-1) for the development of plants between the lines and better in the lines; Comparison between eucalyptus species at 60 months of age and spacing 3 x 2 m (Piracicaba-SP) in which the species E. camaldulensis, E. robusta, E. grandis, IPEF 137, E. urophylla x E. grandis, E. urophylla and E. saligna and in the lines E. camaldulensis, E. robusta, E. grandis, E. urophylla x E. grandis and E. saligna presented reasonable conditions of PAR for the development of plants; Comparison between before and after the pruning in 7 eucalyptus species at 12 months of age and spacing 3 x 2 m (Piracicaba-SP) where there was an increase in PAR after the pruning in the majority of cases, before trawling between the lines only the species H15, E. grandis, E. urophylla, and E. citriodora exhibited reasonable conditions of PAR for the development of plants. After pruning the species H15, I144 and E. grandis, E. urophylla and E. citriodora presented these conditions, in the lines before the pruning none of the species presented conditions After the pruning, species I144, H13, E. urophylla and E. citriodora presented reasonable conditions of RFA for the development of plants; Comparison between three intensities of thinning, 55%, 70% and 85%, in eucalyptus E. grandis with 228 months of age and original spacing 3 x 2 m (Itatinga-SP), where all intensities presented reasonable conditions of PAR for Development of plants, being the highest result obtained in the lines and between the lines of the intensity of 70%; Comparison between 24 species of eucalyptus at 12 months of age and spacing 3 x 2 m (Anhembi-SP), with results between the lines E. citriodora, E. pilularis, E. phaeothrica, E. microcorys, E. deglupta, E. Paniculata, E. tereticornis, E. exserta, E. saligna, E. botryoides, E. grandis, E. urophylla, E. urophylla x E. grandis, E. pellita, E. propinqua, E. resinifera, E. dunni, E. robusta and E. camaldulensis presented reasonable conditions of PAR and the species E. maculata, E.torelliodora and E. cloeziana presented ideal conditions of PAR for the development of plants, in the lines the species E. citriodora, E. pilularis, E E. pylori, E. microcorys, E. deglupta, E. paniculata, E. tereticornis, E. exserta, E. saligna, E. grandis, E. urophylla, E. urophylla x E. grandis, E. pellita, E. propinqua , E. resinifera, E. dunni, E. robusta and E. cloeziana presented reasonable conditions of RFA and E. maculata and E. torelliodora presented ideal conditions of PAR for the development of plants. It was concluded that E. camaldulensis, E. robusta, E. grandis, E. urophylla x E. grandis and E. saligna presented reasonable conditions of PAR at 12 months and at 60 months. The species E. maculata, E. torelliodora and E. cloeziana at 12 months presented ideal conditions of PAR; The thinning had a positive effect on the increase of PAR with the intensities of 70% and 85% compared to that of 55%; Solitary double row eucalyptus plantations allow the PAR to be transmitted through the tree canopy with greater ease in the lines and smaller between the lines, both are favored because there are no rows of trees on one side. The calculation of the IAF by the Lambert-Beer Law allows the identification of this important variable quickly and non-destructively. The use of the Lambert-Beer Law in the majority of the studied cases presented values within the specific for eucalyptus 2 to 4,5 m2 m-2 (Foelkel, 2005).

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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
Entre os insetos pragas que mais preocupam os citricultores no estado do Pará, a mosca-negra-dos-citros, Aleurocanthus woglumi destaca-se por acarretar danos diretos e indiretos ás plantas cítricas, além de constituir praga quarentenária presente ou A2 de alerta máximo, restringindo o comércio com outras regiões. Por ser uma praga exótica, recém introduzida, faltam conhecimentos básicos para a implementação de um manejo adequado na região amazônica. Desse modo, o objetivo do presente trabalho foi avaliar a dinâmica populacional de mosca-negra-dos-citros em pomares de citros em sistema de plantio agroflorestal e monocultura, utilizando a metodologia geoestatística. A área experimental está localizada no município de Capitão Poço onde foram realizadas 12 amostragens durante o período de setembro de 2008 a outubro de 2009, avaliando a presença ou ausência da praga nas laranjeiras em ambos os sistemas de produção. Os resultados obtidos mostraram que o sistema de plantio agroflorestal apresentou maior incidência de plantas com presença de mosca-negra-dos-citros comparado ao sistema de plantio de citros em monocultura, houve influência da temperatura na regulação da população da praga e precipitações elevadas reduziram o número de plantas com presença de A. woglumi. Observou-se que a distribuição espacial da mosca negra dá-se, predominantemente, em agrupamentos com dependência espacial descrita pelo modelo esférico, formando reboleiras de 8,5 a 34m (alcance do modelo) para ambos os sistemas de plantio adotados
Among the insect pests of most concern to citrus growers in the state of Pará (Brazil), the citrus blackfly, Aleurocanthus woglumi stands to cause direct or indirect damage to citrus plants, besides being a pest is present or A2 of this alert, restricting trade with other regions. Being an exotic pest, recently introduced, it lacks basic knowledge for the implementation of appropriate management in the Amazon region. Thus, the objective of this study was to evaluate the population dynamics of blackfly in a citrus orchards from an agroforestry and monoculture plantations, using geostatistical methodology. The experimental area is located in the municipality of Capitão Poço where 12 samples were taken during the period September 2008 to October 2009, evaluating the presence or absence of the pest in orange in both production systems. The results showed that the system of agroforestry plantation had a higher incidence of plants with the presence of citrus blackfly compared with monoculture planting citrus crop, there was influence of temperature on the regulation of pest population and heavy rain reduced the number of plants with presence of A. woglumi. It was observed that the spatial distribution of the blackfly takes place predominantly in clusters with spatial dependence described by the spherical model, forming foci of 8.5 to 34m (range model) for both planting systems adopted

The potential of agroforestry in the British uplands depends largely on the ability of system components to efficiently use resources for which they compete. A typical system would comprise conifers planted at wide spacing, with sheep grazing pasture beneath. Computer models were developed to investigate the growth of trees and pasture in a British upland agroforest system, assuming that growth is primarily a function of light intercepted. Some of the implications of growing trees at wide spacing compared to conventional spacings, and the impact of trees on the spatial and annual production of pasture, were examined. Competition for environmental resources between trees and pasture was assumed to be exclusively for light: below-ground interactions were ignored. Empirical methods were used to try and predict timber production in agroforest stands based on data for conventional forest stands, and data for widely-spaced radiata pine grown in South Africa. These methods attempted to relate stem volume increment to stand density, age, and derived competition measures. Inadequacy of the data base prevented successful extrapolation of growth trends of British stands, although direct extrapolation of the South African data did permit predictions to be made. A mechanistic individual-tree growth model was developed, both to investigate the mechanisms of tree growth at wide spacings, and to provide an interface for a pasture model to examine pasture growth under the shading conditions imposed by a tree canopy. The process of light interception as influenced by radiation geometry and stand architecture was treated in detail. Other features given detailed consideration include carbon partitioning, respiration, the dynamics of foliage and crown dimensions, and wood density within tree stems. The predictive ability of the model was considered poor, resulting from inadequate knowledge and data on various aspects of tree growth. The model highlighted the need for further research into the dynamics of crown dimensions, foliage dynamics, carbon partitioning patterns and wood density within stems, and how these are affected by wide spacing. A pasture model was developed to investigate growth beneath the heterogeneous light environment created by an agroforest tree canopy. Pasture growth was closely related to light impinging on the crop, with temperature having only a minor effect. The model highlighted the fact that significant physiological adaptation (increased specific leaf area, decreased carbon partitioned below-ground and changes in the nitrogen cycle) is likely to occur in pasture shaded by a tree canopy.

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Fundação de Amparo à Pesquisa do Estado do Amazonas
The understanding of dynamics of soil and agroforestry systems is the essential part to establish an appropriate handling of nutrients and their sustaining, since that they provide an increasing in environmental works. The purpose of this study was to evaluate the decomposition and availability of nutrients found in the phytomass of Brazilian chestnut trees, as well as cupuaçu Theobroma grandiflorum (a Brazilian plant very closely related to the cacao tree), Gliricidia sepium, and other combinations among them, based on a agroforestry pattern of system, which is nine years old now. This experiment was carried out at Campo Experimental Confiança, in Roraima, between April and September, which is the period of rainy season. The phytomass of the researched species was put in sacks of decomposition with screens made of polyethylene measuring 0,40 x 0,40, and with mesh of one millimeter in thickness. Those materials were spread on the soil surface to be gathered fortnightly over the whole evaluation period. The experimental design was made with randomized blocks with five replicates. After each gathering, the weight difference between the current gathering and the previous one was regarded as decomposition rate. The values obtained were fitted according to a no linear pattern of logistic type, and having the adjusted coefficient of determination (R2 aj) as criterion of adherence. Brazil nut, cupuaçu and gliricidia leaves showed a distruct behavior relahve to time for decomposition, as gliricidia presented rapid decomposition while cupuaçu leaves showed slowest decomposition cnnidering time assessed. There was no influence concerning association of leaves over decomposition time. Gliricidia leaves presentend high nitrogen, potassium, magnesium and phosforus relaease. Brasil nut and cupuaçu leaves shoewd low nutriente release, specialy nitrogen. Calcium was the nutriente that presentend least release for all species under study, requiring a longer time than time utilized in this study fot its complet release.
A compreensão sobre a dinâmica do sistema solo e planta dos sistemas agroflorestais é parte essencial para estabelecer o manejo adequado de nutrientes e a sua sustentabilidade, proporcionando o incremento nos serviços ambientais. O objetivo deste trabalho foi avaliar a decomposição e a liberação de nutrientes das folhas de castanha-do-Brasil (Bertholletia excelsa), cupuaçu (Theobroma grandiflorum) e gliricídia (Gliricidia sepium) e entre as mesmas, em um sistema agroflorestal com nove anos de idade. O estudo foi conduzido no campo experimental Confiança da Embrapa Roraima, de abril a setembro de 2004, que compreende o período chuvoso na região. As folhas das espécies em estudo foram alocadas em sacos de decomposição de tela de polietileno com dimensão de 0,40 x 0,40 m com malha de 1 mm, os quais foram distribuídos na superfície do solo e coletados quinzenalmente durante todo o período de avaliação. O delineamento experimental utilizado foi de blocos casualizados, com três repetições. Após cada coleta, a diferença de peso entre a coleta atual e a anterior foi considerada como taxa de decomposição. Os valores obtidos foram ajustados segundo modelo não linear do tipo logístico, tendo como critério de aderência o coeficiente de determinação ajustado (R2 aj). As folhas da castanha-do-Brasil, do cupuaçu e da gliricídia apresentaram comportamento distintos quanto ao tempo de decomposição, sendo que as folhas da gliricídia apresentaram mais rápida decomposição, enquanto que as folhas de cupuaçu apresentaram mais lenta decomposição no tempo avaliado. Não se observou influência da associação das folhas sobre o tempo de decomposição. As folhas de gliricídia apresentaram alta liberação de nitrogênio, potássio, magnésio, e fósforo. As folhas de castanha-do-Brasil e cupuaçu apresentaram baixa liberação de nutrientes, especialmente nitrogênio. O cálcio foi o nutriente que apresentou a mais lenta liberação para todos as espécies estudadas, requerendo tempo superior aquele empregado neste estudo para a sua completa liberação.

Silvopastoral systems are a kind of agroforestry system in which trees or shrubs are combined with animals and pastures. Silvopastoral systems are important to intensify pasture production and mitigate climate change effects. However, very few studies have been performed to adapt crop models to simulate these systems. The aim of this study was to parameterize and test the mechanistic crop models APSIM and CROPGRO for estimating Urochloa brizantha cv. BRS Piatã productivity under full sun and in a silvopastoral system, to evaluate the models\' performance to simulate tree-crop interactions, and to develop tools to improve these simulations. For this purpose, four field experiments were conducted under full sun to investigate cutting management under irrigated and rainfed conditions and grazing management under rainfed conditions with high and low N supply. Another experiment was carried out in a silvopastoral system with the trees arranged in simple rows, in East-West orientation, with 15 m between rows and 2 m between plants in the rows. This experiment was conducted under grazing management and rainfed conditions with the pasture variables, microclimate and soil water content being assessed at four distances from the North row (0.00 m, 3.75 m, 7.50 m and 11.25 m). The forage mass simulations for the pasture at full sun, performed using the APSIM-Tropical Pasture model, showed good agreement between observed and estimated data (R2 between 0.82 and 0.97, d between 0.92 and 0.98, and NSE ranging from 0.72 to 0.92), while the simulations with the CROPGRO-Perennial Forage model achieved good precision (R2 between 0.65 and 0.93) and good accuracy (d from 0.86 to 0.97, and NSE from 0.60 to 0.90), for the various managements and environmental conditions. Even considering the promising performance of both models for pastures under full sun, they already needs to be tested in other locations, climate conditions, soils, and grazing or cutting intensities, to prove its accuracy and reach enough confidence. The pasture growth simulations at the silvopastoral system indicated that the APSIM-Tropical Pasture was efficient when only competition by solar radiation was considered (R2 from 0.69 to 0.88, d from 0.90 to 0.96, and NSE between 0.51 and 0.85), but inefficient when considering only competition by soil water (R2 between 0.58 and 0.85, d between 0.58 and 0.82, and NSE from -4.07 to -0.14). The CROPGRO-Perennial Forage achieved good performance on pasture growth simulation at the distances 0.00 m, 3.75 m, and 7.50 m from the trees (R2 from 0.75 to 0.90, d from 0.93 to 0.96, NSE between 0.74 and 0.85). Despite the good results, improvements should be performed in both models for simulating all factors that affect forage growth in silvopastoral systems.
Os sistemas silvipastoris são um tipo de sistema agroflorestal em que árvores ou arbustos são combinados com animais e pastagens. Os sistemas silvipastoris são importantes para a intensificação de pastagens e para a mitigação dos efeitos das mudanças climáticas. Entretanto, poucos estudos vêm sendo realizados visando à adaptação de modelos para a simulação desses sistemas. O objetivo desse estudo foi parametrizar e testar os modelos mecanísticos APSIM e CROPGRO para estimar a produtividade de Urochloa brizantha cv. BRS Piatã a pleno sol e em um sistema silvipastoril, avaliar o desempenho dos modelos para simular as interações árvore-pastagem e desenvolver ferramentas para aprimorar tais simulações. Para isso, foram conduzidos quatro experimentos de campo, a pleno sol, para avaliar diferentes manejos da pastagem: corte, em irrigado e sequeiro; e pastejo, em sequeiro e com alto ou baixo suprimento de nitrogênio. Outro experimento foi conduzido em um sistema silvipastoril com as árvores arranjadas em renques simples, com orientação Leste-Oeste, com espaçamento de 15 m entre renques e 2 m entre plantas nos renques. Esse experimento foi conduzido sob pastejo e em sequeiro, com avaliações das variáveis da pastagem, microclima e água no solo em quatro distâncias em relação ao renque Norte (0,00 m; 3,75 m; 7,50 m and 11,25 m). As estimativas de massa de forragem a pleno sol, realizadas com o modelo APSIM-Tropical Pasture, apresentaram boa concordância entre os dados observados e os estimados (R2 entre 0,82 e 0,97, d entre 0,92 e 0,98 e NSE de 0,72 a 0,92), enquanto que, as estimativas geradas pelo modelo CROPGRO-Perennial Forage alcançaram boa precisão (R2 entre 0,65 e 0,93) e boa exatidão (d entre 0,86 e 0,97 e NSE de 0,60 a 0,90), para os diferentes manejos e condições ambientais. Mesmo considerando o desempenho promissor de ambos os modelos para simular pastagens a pleno sol, para confirmar a acurácia e a eficiência destes, são necessários testes em outros locais, condições climáticas, tipos de solo e intensidades de corte ou pastejo. As simulações do crescimento da pastagem no sistema silvipastoril indicaram que o modelo APSIM-Tropical Pasture, foi eficiente quando somente a competição por radiação solar foi considerada (R2 de 0,69 a 0,88, d entre 0,90 e 0,96 e NSE de 0,51 a 0,85), mas ineficiente quando somente a competição por água no solo foi considerada (R2 entre 0,58 e 0,85, d entre 0,58 e 0,82 e NSE de -4,07 a -0,14). O modelo CROPGRO-Perennial Forage atingiu bom desempenho na simulação do crescimento da pastagem para as distâncias 0,00 m, 3,75 m e 7,50 m em relação às árvores (R2 de 0,75 a 0,90, d entre 0,93 e 0,96, NSE de 0,74 a 0,85). Apesar dos bons resultados, ambos os modelos devem ser melhorados para simular todos os fatores que afetam o crescimento de pastagens em sistemas silvipastoris.

O principal objetivo do trabalho foi avaliar o impacto no bem-estar social e a viabilidade financeira de sistemas agroflorestais (SAFs) na Amazônia brasileira com a utilização de modelos de simulação desenvolvidos com dinâmica de sistemas. Para isso foi proposto um SAF teórico de referência, elaborado a partir de informações reais de experimentos de longa duração disponibilizados através de diversas publicações e a partir das características edafoclimáticas e socioeconômicas dos municípios cobertos pela Operação Arco Verde. O modelo agrossilvicultural apresentado é composto por culturas anuais, cultivadas durante implantação do sistema e em uma faixa especificamente destinada a esse fim, uma fruteira semi-perene e outra perene, uma espécie florestal e outra destinada à adubação verde. As espécies utilizadas para esse sistema foram mandioca (Manihot sculenta), milho (Zea maiz), banana (Musa spp.), cupuaçu (Theobroma grandiflorum), castanha-do-brasil (Berthollethia excelsa) e ingá (Inga edulis). Para o planejamento e análise financeira, foi desenvolvida uma planilha em Excel e simulações juntamente com análises de sensibilidade e das distribuições de probabilidade de alguns indicadores foram realizadas através de modelos de dinâmica de sistemas desenvolvidos com o Vensim DSS. O sistema de referência proposto apresentou-se capaz de gerar receitas durante todo o ciclo de cultivo, estimado em vinte anos, sendo viável financeiramente. Foi constatada a alta sensibilidade de SAFs à utilização de mão-de-obra familiar e às variações na taxa de juros. Além disso, foi verificada a baixa sensibilidade dos SAFs a variações nos preços dos produtos, caracterizando oferta inelástica. Um modelo de simulação para avaliar a adoção de SAFs em substituição a sistemas de produção não sustentáveis e suas relações com o estado do ambiente e com a oferta de serviços ambientais foi desenvolvido posteriormente. Após as simulações em vários cenários e a realização de análises de sensibilidade, com base no comportamento do modelo e na dinâmica das alterações pertinentes às éticas de consumo e de produção pode-se afirmar que, mediante à multifuncionalidade da agricultura e à produção conjunta de commodities agrícolas e de serviços ambientais pelos SAFs, aumentos na disposição a pagar, como forma de remuneração por serviços ambientais produzidos conjuntamente pelos SAFs, influenciam a dinâmica da adoção de sistemas agroflorestais e a utilização de SAFs na Amazônia brasileira promove acréscimos no bem-estar social, a partir do aumento de utilidade caracterizado por níveis mais altos de serviços ambientais.
This work had as its main objective to assess the financial viability and the impact on social welfare of agroforestry systems (AFS) in the Brazilian Amazon with the use of system dynamics simulation models. For this it was proposed a theoretical reference AFS based on information compiled from actual long-term experiments available through various publications and from the soil, climate and socioeconomic characteristics of the municipalities covered by Operação Arco Verde. The agroforestry model presented is composed of annual crops grown for system deployment and in a band specifically designated for such purposes, a fruit and a semi-evergreen perennial, one forest species and another devoted to green manure. The species used for this system were cassava (Manihot sculenta), maize (Zea maiz), banana (Musa spp.) cupuassu (Theobroma grandiflorum), brazil-nut (Berthollethia excelsa) and inga (Inga edulis). For financial planning and analysis, it was developed an Excel spreadsheet and simulations along with sensitivity analysis and probability distributions of some indicators were done using system dynamic models developed with Vensim DSS. The reference system proposed was able to generate revenue during the entire crop cycle, estimated at twenty years, being financially viable. It was noted the high sensitivity of AFS to the use of family manpower and to changes in interest rates. Moreover, there was the low sensitivity of AFS to variations in product prices, characterizing inelastic supply. A simulation model to evaluate the adoption of agroforestry systems to replace non-sustainable production systems and their relations with the state of the environment and the provision of environmental services was developed later. After the simulations in various scenarios and conducting sensitivity analysis, based on the model behavior and dynamics of the relevant amendments to the ethics of consumption and production, can be stated, upon the multifunctionality of agriculture and the joint production of agricultural commodities and environmental services, that increases in willingness to pay, as compensation for environmental services produced jointly by the AFS, influence the dynamics of the adoption of agroforestry and the use of agroforestry systems in the Brazilian Amazon promotes increases in social welfare from increasing utility characterized by higher levels of environmental services.

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Capes
A Caatinga, vegetação que cobre a maior parte da região semiárida, encontra-se sob forte pressão das atividades humanas resultante de sistemas de produção baseados em práticas agrícolas rudimentares, superpastejo e exploração de madeira indiscriminada. É necessário desenvolver um modelo de exploração que possa garantir o equilíbrio dos ecossistemas e a satisfação econômica e social do homem. Os Sistemas Agroflorestais (SAF's) apresentam-se como alternativa, pois preconizam a sustentabilidade dos ecossistemas baseada na biodiversidade e na recuperação de fragmentos florestais. O êxito implantação dos SAF's depende do conhecimento das potencialidades dos recursos da área em que se deseja aplicálo. Assim, este estudo teve como objetivo realizar um levantamento do estado atual da Fazenda NUPEÁRIDO e diagnosticar a situação ambiental nos limites da propriedade. Procedeu-se ao levantamento da área total da propriedade, classificação das características morfológica, física e química dos solos, estudos fitossociológicos da vegetação arbórea e avaliação das pastagens. Verificou-se que a fazenda possui uma área total de aproximadamente 263 ha, sendo 42% inundados pelas águas do açude Jatobá, quando se encontra no seu nível máximo. As demais áreas encontram-se distribuídas em área de Caatinga arbustiva arbórea aberta (90 ha) e pastagem (57 ha). Os solos são relativamente homogêneos e apresentam-se com limitações quanto à profundidade, estrutura, textura e fertilidade. A área florestada apresenta fisionomia aberta, sendo classificada como arbustiva arbórea aberta, apresentando considerável riqueza de espécies, destacando-se as famílias Fabaceae e Euphorbiaceae com maior número de indivíduos. As áreas de pastagem nativa compostas por vegetação herbácea apresentam-se muito degradadas devido o superpastejo contínuo de bovinos, caprinos e ovinos. O desenvolvimento dos SAF's na propriedade depende da intervenção de pesquisadores dos cursos ofertados pela UFCG/CSTR, sobretudo, na escolha de ações prioritárias que devem ser implantadas em caráter emergencial, como recuperar a mata ciliar do açude Jatobá, combater a retirada da vegetação arbórea, manejar as áreas de pastejo e recuperar áreas degradadas. Espera-se que a adoção dos SAF's seja um modelo didático a ser seguido por outras instituições, agentes de extensão e proprietários rurais da região semiárida, mas, sobretudo, a garantia da utilização sustentável dos recursos naturais desta propriedade.
Caatinga, the vegetation that covers most of the semiarid region in northeast Brazil is under heavy anthropic pressure due to production systems based on incorrect agricultural practices, overgrazing and indiscriminate logging. It is necessary to develop an exploration model that balances ecosystems and human social and economic needs. Agroforestry happens to be a viable alternative as they support the idea of ecosystem sustainability based on recovery of biodiversity and of forest fragments. Successful implementation of agroforestry depends on the knowledge of the potentialities of the resources present in the target area. Thus, this study had the objective to survey the current status of NUPEARIDO Farm and to make a diagnosis of its environmental conditions. Data were collected on the total area of the farm, morphological, chemical, and physical soil attributes, tree phytossociology, and pasture evaluation. The farm covers approximately 263 ha, 42% of them may be under water when Jatobá dam is in its highest level. Open Caatinga forest covers 90 ha and pasture57 ha. The soils in the farm are relatively homogeneous, presenting limitations regarding depth, structure, texture and fertility. The forested area was classified as open bushy-arboreal Caatinga with a relatively high tree species richness, mostly from the Fabaceae and Euphorbiaceae families. The native herbaceous pasture areas are under a heavy continuous browsing pressure by cattle, goats and sheep. The adoption of agroforestry systems at NUPEARIDO Farm needs the support of the UFCG/CSTR researcher team in order to define priorities actions that should be implemented right away, such as recovery of the degraded areas, in general, and the bordering forest around the Jatobá dam, prevention of wood and firewood collection, and adoption of proper browsing pressure on pasture areas. The expectations are that the adoption of agroforestry systems be used as a didactic model to be followed by other institutions, extension agents and local farmers, and especially that the adopted systems warrant the sustainable use of the natural resources available at NUPEARIDO Farm.

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Devido ao aumento gradativo do número de processos de licenciamento ambiental com objetivo de recuperar áreas degradadas, prevê-se uma situação de insolvência para os próximos anos na gestão ambiental. Deste modo, torna-se imperiosa a concepção de novas tecnologias baseadas na web que permitam inovação no sistema de gestão dos recursos naturais, principalmente para a recuperação de áreas degradadas. Assim, nesta pesquisa investigou-se a aplicação dos sistemas inteligentes como uma alternativa para à tomada de decisões durante a elaboração e gestão de projetos de recuperação de áreas degradadas. O objetivo desta pesquisa é analisar os impactos para a melhoria do processo de elaboração e avaliação de projetos de recuperação de áreas degradadas com a utilização do Sistema de Elaboração de Projetos de Recuperação de Áreas Degradadas. A simulação dos experimentos dos projetos de recuperação de áreas degradadas priorizou empreendimentos em propriedades rurais, os quais são responsáveis pelo maior número de processos para regularização e licenciamento ambiental. As aplicações dos experimentos no Sistema de Elaboração de Projetos de Recuperação de Áreas Degradadas resultaram, nas configurações para os projetos de qualquer situação em áreas rurais ou urbanas, na descrição dos experimentos, nas regras para permitir as recomendações técnicas através das combinações das perguntas e respostas, na descrição atual do fluxo dos processos de regularização e licenciamento ambiental com projetos de recuperação de áreas degradadas e na descrição de um sistema de gestão ambiental, exclusivo para áreas degradadas. Conclui-se, que o Sistema de Elaboração de Projetos de Recuperação de Áreas Degradadas, apresenta um impacto positivo, tanto para aqueles que analisam os projetos, quanto para os que os elaboram, e demonstrou-se uma solução educativa eficiente no gerenciamento de processos com projetos de recuperação de áreas degradadas. É uma ferramenta da inteligência artificial para auxiliar à tomada de decisões, com um banco de dados inicial, em desenvolvimento e classificado como sistema especialista de planejamento. Pois a análise mais aprofundada sobre os impactos ambientais da área degradada, compete ao especialista, recomendar as alternativas que levem ao sucesso da recuperação do passivo ambiental. Este sistema poderá ter conexão com outros sistemas utilizados na gestão ambiental, e visará garantir maior eficiência e efetividade como um todo, alinhando-se, sobretudo, às novas regras trazidas pela legislação.
Due to the gradual increase in the number of environmental licensing procedures in order to recover degraded areas, is expected to become insolvent in the coming years in environmental management. Thus, it becomes imperative to design new web-based technologies that enable innovation in the management of natural resources system, principally for the recovery of degraded areas. Thus, in this study we investigated the application of intelligent systems as an alternative to the decision-making during the development and management of degraded areas recovery projects. The objective of this research is to analyze the impacts to improve the process of preparing and assessment of degraded areas recovery projects using the System Preparation of Degraded Area Recovery Project. The simulation experiments of degraded areas recovery projects prioritized projects in rural properties, which are responsible for the greatest number of processes for regulation and environmental licensing. The applications of experiments in the Degraded Area Recovery Project Development System resulted in the settings for projects of any situation in rural or urban areas, in the description of the experiments, the rules to allow the technical recommendations through combinations of questions and answers in the present description of the flow of regularization processes and environmental licensing with degraded areas recovery projects and the description of an environmental management system, unique to degraded areas. It follows that the Area Recovery Project Development System Degraded, has a positive impact, both for those who analyze the projects, and for those who make them, and proved to be an efficient solution in educational management processes recovery projects of degraded areas. It is an artificial intelligence tool to aid decision making, with an initial database, developing and classified as expert planning system. For further analysis of the environmental impacts of the degraded area, it is for the expert, recommend alternatives that lead to successful recovery of environmental liabilities. This system may have connection with other systems used in environmental management and will aim at ensuring greater efficiency and effectiveness as a whole, lining up, especially with the new rules introduced by legislation.

Conselho Nacional de Desenvolvimento Científico e Tecnológico
The agroforestry systems offer advantages and improvements to the environment, alternative income for family farmers, providing improvement of the life quality in a more sustainable way. This study aimed to analyze the forestry component in different spatial arrangements of agroforestry systems in relation to economic and financial viability in the region of Vale do Jaguari, RS through the lifting of costs from maintenance and deployment, revenues from the sale of forest products from two different rotations of 10 and 15 years, in addition to a sensitivity analysis of the market price for the two simulations, variation of interest rate and reduction of the final production. Eight agroforestry systems were analyzed, five were implanted with only one tree species (eucalyptus) on each system, and the other three with different tree species (Eucalyptus sp. and Acacia mearnsii). The survey data was conducted in two stages: a questionnaire of the open type to producers for the preparation of the area how was the forest implanted, cultivation and other questions about the property and the second stage was conducted through the forest inventory in the eight-agroforestry systems. The indicators selected for economic and financial analysis were Net Present Value (NPV), Equivalent Annual Value (EAV), Internal Rate of Return (IRR), reason Benefit / Cost (B/C) and Production Average Cost (PAC) where the discount rate used was 7.5% per year. The price of wood as a final product for the 10 year rotation was R$ 25.00 per stereo meter, while for the rotation of 15 years was R$ 100.00 per cubic meter, product destined for sawmills. Costs in relation to forest harvesting were not counted because the forest was sold standing. The economic and financial viability in all agroforestry systems was feasible for the rotation of 10 and 15 years, however the greatest financial return was for the rotation of 15 years. As regards the sensitivity analysis, considering the variation of the selling price of the final product and reducing the final production, all simulations performed for both rotations were viable. Regarding the change in interest rate and NPV, the system was viable, remained positive to higher interest rates. This economic and sensitive analysis is very important for family farmers because it generates control and risk prevention making it feel safer to invest in this type of system and end of rotation make a new agroforestry system cycle. In addition, the benefits are not only economic but also generate improvements to the environment through the intensive use of land, most biodiversity in the same area and better acclimatization of the animals present in the system.
Os sistemas agrossilvipastoris oferecem vantagens e melhorias ao meio ambiente, alternativa de renda aos produtores rurais familiares, proporcionando melhoria na qualidade de vida de modo mais sustentável. Esse trabalho teve por objetivo analisar o componente florestal em diferentes arranjos espaciais nos sistemas agrossilvipastoris em relação a viabilidade econômico-financeira na região do Vale do Jaguari, RS por meio do levantamento dos custos de implantação e manutenção, receitas oriundas da venda dos produtos florestais para duas rotações diferentes de 10 e 15 anos, além de fazer uma análise de sensibilidade do preço de mercado para as duas simulações, variação da taxa de juro e redução da produção final. Foram analisados oito sistemas agrossilvipastoris, sendo que cinco foram implantados com apenas uma espécie arbórea (eucalipto) em cada sistema, e os outros três com diferentes espécies arbóreas (eucalipto e acácia-negra). O levantamento dos dados foi realizado em duas etapas: aplicação do questionário do tipo aberta aos produtores em relação ao preparo da área, modo de implantação da floresta, tratos culturais entre outros questionamentos sobre a propriedade e a segunda etapa através do inventário florestal nos oito sistemas agrossilvipastoris. Os indicadores selecionados para a análise econômico-financeiro foram Valor Presente Líquido (VPL), Valor Anual Equivalente (VAE), Taxa Interna de Retorno (TIR), razão Benefício/Custo (B/C) e Custo Médio de Produção (CMPr), em que a taxa de desconto utilizada foi 7,5% ao ano. O preço da lenha como produto final para a rotação de 10 anos foi de R$ 25,00 por metro estéreo, enquanto que para a rotação de 15 anos foi de R$ 100,00 por metro cubico, produto destinado para serraria. Os custos em relação a colheita florestal não foram contabilizados pois a floresta foi vendida em pé. A viabilidade econômico-financeira em todos os sistemas agrossilvipastoris foi viável para a rotação de 10 e 15 anos, porem o maior retorno financeiro foi para a rotação de 15 anos. No que se refere a análise de sensibilidade, considerando a variação dos preços de venda do produto final e redução da produção final, todas as simulações realizadas para ambas as rotações foram viáveis. Em relação a variação da taxa de juros e VPL, o sistema foi viável, ou seja, manteve-se positivo até as taxas de juros mais elevadas. Essa análise econômico-financeira e de sensibilidade é de fundamental importância para o produtor rural familiar, pois gera controle e prevenção de risco fazendo que o mesmo sinta-se mais seguro ao investir nesse tipo de sistema e no final da rotação faça um novo ciclo de sistema agrossilvipastoril. Adicionalmente, os benefícios não são apenas econômicos mas também são geradas benfeitorias ao meio ambiente por meio do uso intensivo da terra, maior biodiversidade em uma mesma área e melhor aclimatação dos animais presente no sistema.

This study had as objective to evaluate a mixed stand of Eucalyptus urograndis and Acacia mearnsii in an agroforestry system with corn (Zea mays L.). The study was conducted in Bagé county, in a partnership with VCP (Votorantim Celulose e Papel) company. The study was installed in December 2006, with five different treatments (T1- 100% eucalyptus; T2- 100% black-wattle; T3- 50% eucalyptus+ 50% blackwattle; T4- 75% eucalyptus + 25% black-wattle and T5- 25% eucalyptus + 75% black-wattle), with 4 m x 1,5 m planting space. Three lines of corn were planted, between the eucalyptus and/or black-wattle lines. 10 months after the installation, a inventory was done, where all the stem diameters and the total height were measures, for further volume determination. At the same time the biomasses from forest species were quantified, they were separated in fractions (leave, branch and stem). Corn biomass was collected in the end of the cycle and separated in fractions (leave, straw, grain, corn cob and stem). Homogeneous eucalyptus and black-wattle stands did not differ in height and stem diameter related to mixed stand. Black-wattle cylindrical volume, both in homogeneous and mixed stand was higher for eucalyptus, because showed a highest initial growth. In mixed stands, the treatment T5 (25E:75A) showed a highest biomass accumulation, being 35,1% in the leaves, 25,8% in branches and 39,1% in stem. Biomass accumulation for each fraction, had the following order, for T1 and T3: stem>branch>leaf and, for T2, T3, T4 and T5: stem>leaf>branch. The highest levels of nutrients in trees biomass, are in the leaves, followed by branches and stem. Black-wattle in homogeneous stands, showed highest nutrients accumulation, because it had the highest amount of total biomass. The highest percentage of corn grains was observed in T4 (75E:25A), with 38,4% from the total biomass of this treatment. Grains showed the highest amounts for N, P, Mg, B and Zn. In treatment T4 (75E:25A), corn exported more nutrients, because showed the highest grain production.
O objetivo deste estudo foi avaliar um plantio misto de Eucalyptus urograndis e Acacia mearnsii em sistema agroflorestal com milho (Zea mays L.). O estudo foi realizado no município de Bagé, em parceria com a VCP (Votorantim Celulose e Papel). A implantação da pesquisa foi em dezembro de 2006, com cinco tratamentos diferentes (T1- 100% eucalipto; T2- 100% acácia-negra; T3- 50% eucalipto + 50% acácia-negra; T4- 75% eucalipto + 25% acácia-negra e T5- 25% eucalipto + 75% acácia-negra), com espaçamento de 4 m x 1,5 m. Foram plantadas 3 linhas de milho, entre as fileiras de eucalipto e/ou acácia-negra. Aos 10 meses de plantio, foi realizado um inventário na área, sendo medidos, o diâmetro do colo e a altura total, para posterior determinação do volume. Na mesma ocasião foi quantificada a biomassa das espécies florestais, que foram separadas por frações (folha, galho e tronco). A biomassa do milho foi coletada no final do ciclo e separada por frações (folha, palha, grão, sabugo e colmo). O plantio homogêneo de eucalipto e acácianegra, não diferiu em altura e diâmetro do colo em relação ao plantio misto. O volume cilíndrico da acácia-negra, tanto em plantio homogêneo como misto, foi maior que para o eucalipto, pois apresentou maior crescimento inicial. Em plantio misto o tratamento T5 (25E:75A) apresentou o maior acúmulo de biomassa, sendo 35,1% nas folhas, 25,8% nos galhos e 39,1% no tronco. O acúmulo de biomassa para cada fração, teve a seguinte ordem, para T1 e T3: tronco>galho>folha e, para T2, T4 e T5: tronco>folha>galho. Os maiores teores de nutrientes da biomassa das árvores, encontram-se nas folhas, seguidas de galhos e tronco. A acácia-negra em plantio homogêneo, apresentou maior acúmulo de nutrientes, pois teve maior quantidade de biomassa total. A maior porcentagem de grãos de milho, foi observada no T4(75E:25A), com 38,4% da biomassa total deste tratamento. Os grãos, apresentaram os maiores teores para N, P, Mg, B e Zn. No tratamento T4(75E:25A), a cultura do milho exportou mais nutrientes, por apresentar maior produção de grãos.

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Nitrate leaching can cause surface water pollution due to the addition of nitrogen fertilizer, which can also generate economic losses for the farmer. This study aimed to determine the leaching of nitrate and ammonium after the addition of N-urea in different systems of land use: Coffee Agroforestry System (SAF), Coffee Full Sunlight (CPS) and Pasture System (SP), compared with Secondary Forest (M). The experiment was conducted in a completely randomized design arranged in a factorial 1 + (3x2). The Secondary Forest was a reference and three agricultural systems used two doses of N-urea (50 and 200 kg ha-1) in SP and two doses of N-urea (200 and 450 kg ha-1) in SAF and CPS, with three replications each. The experiment was conducted on the property of family farmers in the Municipality of Araponga Zona da Mata of Minas Gerais, in a Red Yellow Latosol clay. Soil solution was collected at depths of 0.2 and 0.6 m. after each rainfall to analyze NO3- and NH4+ concentrations. At the end of the experiment, the accumulated contents of NO3- with high doses of N-urea at a depth of 0.6 m were measured at 2.18 mg/835.67 mL of soil solution in the SP, 13.28 mg/494.67 mL of soil solution in SAF and 23.6 mg/729 mL of soil solution in CPS. There was no effect of N-urea rate within the system. We concluded that the reduced NO3- loss in SP, SAF and CPS at a depth of 0.6 m was associated with higher soil clay content. It was not influenced by management systems or by high doses of N in the coffee culture under the conditions studied. Therefore, there is not a risk of groundwater contamination by leaching of NO3- and NH4+.
A lixiviação de nitrato pode causar poluição das águas superficiais devido à adição de fertilizantes nitrogenados, gerando também perdas econômicos ao agricultor. O presente trabalho teve como objetivo determinar a lixiviação de nitrato e amônio após adição de N-uréia em diferentes sistemas de uso do solo: Café Sistema Agroflorestal (SAF), Café Pleno Sol (CPS) e Sistema pastagem (SP), comparados com a Mata Secundaria (M). O experimento foi conduzido em delineamento experimental inteiramente casualizado organizado em esquema fatorial 1 + (3x2), sendo a Mata Secundaria como referência e três sistemas agrícolas, com duas doses de N-uréia (50 e 200 kg ha-1) no SP e duas doses de N-uréia (200 e 450 kg ha-1) no SAF e CPS, com três repetições. O experimento foi realizado na propriedade de agricultor familiar, no município de Araponga - Zona da Mata de Minas Gerais, num solo Latossolo Vermelho Amarelo de textura argilosa. Para a coleta da solução de solo se instalou, nas profundidades de 0,2 e 0,6 m, extratores de cápsulas porosas de cerâmica, as soluções de solo foram coletadas depois de cada ocorrência de chuva e levadas ao laboratório para o analises de NO3- e NH4-. No final do experimento os conteúdos acumulados de NO3-, com alta doses de N-uréia, na profundidade de 0,6 m foram: 2,18 mg/835,67 ml de solução de solo no SP; 13,28 mg/494,67 ml de solução de solo no SAF e 23,6 mg/729,33 ml de solução de solo no CPS. Não houve efeito de dose de N-uréia dentro dos sistemas. Conclui-se que A reduzida perda de NO3- no SP, SAF e CPS, na profundidade de 0,6 foi associada ao maior teor de argila do solo e não pela influencia do sistema de manejo e que as aplicações de altas doses de N na cultura de café baixo as condições estudadas, não são um risco de contaminação do lençol freático pela lixiviação do NO3- e NH4+.

Resumo: Entre os insetos pragas que mais preocupam os citricultores no estado do Pará, a mosca-negra-dos-citros, Aleurocanthus woglumi destaca-se por acarretar danos diretos e indiretos ás plantas cítricas, além de constituir praga quarentenária presente ou A2 de alerta máximo, restringindo o comércio com outras regiões. Por ser uma praga exótica, recém introduzida, faltam conhecimentos básicos para a implementação de um manejo adequado na região amazônica. Desse modo, o objetivo do presente trabalho foi avaliar a dinâmica populacional de mosca-negra-dos-citros em pomares de citros em sistema de plantio agroflorestal e monocultura, utilizando a metodologia geoestatística. A área experimental está localizada no município de Capitão Poço onde foram realizadas 12 amostragens durante o período de setembro de 2008 a outubro de 2009, avaliando a presença ou ausência da praga nas laranjeiras em ambos os sistemas de produção. Os resultados obtidos mostraram que o sistema de plantio agroflorestal apresentou maior incidência de plantas com presença de mosca-negra-dos-citros comparado ao sistema de plantio de citros em monocultura, houve influência da temperatura na regulação da população da praga e precipitações elevadas reduziram o número de plantas com presença de A. woglumi. Observou-se que a distribuição espacial da mosca negra dá-se, predominantemente, em agrupamentos com dependência espacial descrita pelo modelo esférico, formando reboleiras de 8,5 a 34m (alcance do modelo) para ambos os sistemas de plantio adotados
Abstract: Among the insect pests of most concern to citrus growers in the state of Pará (Brazil), the citrus blackfly, Aleurocanthus woglumi stands to cause direct or indirect damage to citrus plants, besides being a pest is present or A2 of this alert, restricting trade with other regions. Being an exotic pest, recently introduced, it lacks basic knowledge for the implementation of appropriate management in the Amazon region. Thus, the objective of this study was to evaluate the population dynamics of blackfly in a citrus orchards from an agroforestry and monoculture plantations, using geostatistical methodology. The experimental area is located in the municipality of Capitão Poço where 12 samples were taken during the period September 2008 to October 2009, evaluating the presence or absence of the pest in orange in both production systems. The results showed that the system of agroforestry plantation had a higher incidence of plants with the presence of citrus blackfly compared with monoculture planting citrus crop, there was influence of temperature on the regulation of pest population and heavy rain reduced the number of plants with presence of A. woglumi. It was observed that the spatial distribution of the blackfly takes place predominantly in clusters with spatial dependence described by the spherical model, forming foci of 8.5 to 34m (range model) for both planting systems adopted
Orientador: Arlindo Leal Boiça Junior
Coorientador: Paulo Roberto Silva Farias
Banca: José Carlos Barbosa
Banca: José Roberto Scarpellini
Mestre

While the light regimes of closed forest strands and open pasture have been quantitatively described and modelled, agroforestry involves greater complexity and spatial variability. This research involved intensive measurement of quantum flux density (QFD) above and below re-spaced tree strands of Sitka spruce (Picea sitchensis [Bong.] Carr.) and hybrid larch (Larix x eurolepis Henry) in conjunction with measurement of tree growth. QFD was also measured above and below pasture growing in boxes in imported soil sunk to ground level beneath the trees. The Monteith hypothesis that crop growth in unstressed conditions is linearly related to the amount of QFD intercepted by its canopy was found to hold for above ground growth of trees at agroforestry spacings. The overall dry matter: QFD quotient (e) for Picea sitchensis across the range of tree frequencies was 0.32 g mol^-1 which is lower than typical values reported for agricultural crops, young container grown trees of Salix viminalis and Populus trichocarpa and closed-canopy Picea sitchensis, but comparable with previous estimates for a range of mature tree stands. e was unaffected by tree spacing, but was significantly higher for the tall tree stand which had been pruned. The mean annual QFD transmitted to the understorey varied from 39% to 96% of that in the open across the agroforestry treatments. The mean transmittance was similar but spatial variability of QFD was significantly higher in tree stands with crown to ground level when compared with stands having similar crown dimensions but which had been pruned to approximately 1.3 m height. More than 90% of seasonal pasture growth could be explained by a regression of growth on incident QFD.

Air pollution can lead to environmental impacts. Over the past decades there have been some success stories reducing pollutant emission, namely sulphur dioxide (SO2). However, impacts on ecosystems from atmospheric nitrogen (N) pollution are still seen as a major threat for European biodiversity. Across Europe over 70% of Natura 2000 sites are at risk for eutrophication with over 70% of the Natura 2000 area in Europe (EU28( exceeding critical loads for nutrient nitrogen deposition. Agricultural ammonia is a key contributor to the threat to these sites due to the close proximity of agricultural activities and protected sites. Source attribution modelling using an atmospheric transport model showed that agricultural livestock production in the UK is the dominant nitrogen source for N disposition across the UK Natura 2000 network. Nearly 90% of all sites had livestock as their dominant source, contributing 32% of the total nitrogen deposition across the whole network. 76% of all Special Areas of Conservation (SAC) sites exceeded their critical load for nutrient nitrogen, representing 74% of the entire SAC area. The extent of exceedance is also notable with many sites experiencing depositions of >50 kg N/ha/yr over the critical load. the situation for acidity critical load exceedance is less sever, by 51% of sites are still exeeded. Legislation to regulate pollutant emissions to air and protect biodiversity are often not integrated, and there has been no common European approach for determining the impacts of nitrogen deposition on individual Natura sites, or on conservation status. Off-site sources of air pollution present difficulties in assessing and attributing impacts, because deposition can result from local sources (1-2 km), or very far away sources (>1000 kms). Managing nitrogen losses on the farm and improving the efficient use of nitrogen are key components for overall reduction in NH3 emissions. Many nitrogen management options are available to abate ammonia from agricultural activities. On the one hand, technical and management measures include controlling emissions from manure storage and spreading, livestock feeding strategies, and improving housing systems. Trees, on the other hand, are effective scavengers of both gaseous and particulate pollutants from the atmosphere, making tree belts potentially effective landscape features to support ammonia abatement strategies. Using a coupled deposition and turbulence model the recapture efficiency of tree planting around ammonia sources was estimated. Using different canopy structure scenarios, tree depths and differing leaf area density (LAD) and leaf are index (LAI) were adjusted for a main canopy and a backstop canopy. Recapture efficiency for ammonia ranged from 27% (trees planted around housing systems), up to 60% (under-story livestock silvopastoral systems). Practical recapture potential was set at 20% and 40% for housing and silvopastoral systems respectively. Model results from scaling up to national level suggest that tree planting in hot spot areas of ammonia emissions would lead to reduced N deposition on nearby sensitive habitats. Scenarios for on-farm emission control through tree planting showed national reductions in nitrogen deposition to semi-natural areas of 0.14% (0.2 kt N-NHx) to 2.2% (3.15 kt N-NHx). Scenarios mitigating emissions from cattle and pig housing yielded the highest reductions. The afforestation strategy showed national-scale emission reductions of 6% (8.4 kt N-NHx) to 11% (15.7 kt N-NHx) for 25% and 50% afforestation scenarios respectively. Increased capture by the planted trees also generated an added benefit of reducing long-range transport effects, including a decrease in wet deposition of up to 3.7 kt N-NHx (4.6%) and a decrease in export from the UK of up to 8.3 kt N-NHx (6.8%). Agroforestry measures for ammonia abatement were shown to be cost-effective for both planting downwind of housing and in silvopastoral systems, when costs to society were taken into account. Planting trees was also cost-effective from a climate change perspective. Comparing the cost per kg of NH3 abated showed that planting trees is a method of ammonia emission mitigation comparable with other (technical) measures. The costs for planting trees downwind of housing were calculated at €2.6-7.3/kg NH3. Agroforestry for ammonia abatement offers multiple benefits for the farmer and synergistic effects for society as a whole including i) carbon sequestration. ii) visibility screening around housing units, iii) imporved animal welfare for silvopastoral systems, iv) reducing critical load exceedance on protected sites, v) price advantage of 'woodland chick' productions, vi) supporting the Industrial Emission Directive (IED) requirements for emission reduction, vii) supporting national afforestation policies. The results of this work support the notion that in the emerging discussion about the values of ecosystem services and the role of nature-based solution to tackle persistent environmental challenges, tree planting has a large potential in rural and urban environments.

A produção de café é uma atividade importante para a economia do Brasil, maior produtor e também principal exportador. O cafeeiro apresenta ciclo bienal de produção, cuja oscilação é acentuada no Brasil dada às condições climáticas e ao sistema de cultivo predominante a pleno sol. Pesquisas envolvendo avaliação do estado nutricional do cafeeiro em sistemas agroflorestais são raras, o que dificulta as recomendações de adubação para esta condição. Objetivou-se neste estudo, o melhor entendimento da fertilidade do solo e do estado nutricional do cafeeiro em relação aos teores de N e K no microclima gerado pelo sistema agroflorestal e em monocultivo. A pesquisa foi conduzida no período de março de 2006 a maio de 2008, no campo experimental pertencente ao Departamento de Produção Vegetal da Escola Superior de Agricultura Luiz de Queiroz da Universidade de São Paulo (ESALQ/USP) em Piracicaba SP, localizada nas coordenadas geográficas 220 42 20 S, 470 37 22 W e altitude 565 m. O experimento foi composto de seringueiras do clone PB 235, plantada em dezembro de 1991, no espaçamento de 8,0 x 2,5 m e cafeeiros cv. Obatã IAC 1669-20, plantado em janeiro de 2002, no espaçamento de 3,4 x 0,9 m, sob diferentes condições de sombreamento: no sub-bosque e interfaceando as árvores da seringueira e em monocultivo. O delineamento experimental adotado foi o inteiramente casualizado com quatro repetições. O experimento de avaliação da fertilidade do solo constou de seis tratamentos, constituídos pelas radiações sobre o solo: 1) 6,4%; 2) 7%; 3) 35,4%; 4) 47,5%; 5) 60,9%; 6) 64,9%. O experimento de avaliação dos teores foliares de N e K do cafeeiro constou de quatro tratamentos, constituídos pelas radiações sobre os cafeeiros: 1) 35%; 2) 45%; 3) 90%; 4) 100%. O estudo constou, adicionalmente, dos experimentos de deposição e avaliação da velocidade de decomposição da serapilheira, frações da matéria orgânica, crescimento, peso foliar específico, anatomia foliar, maturação dos frutos e produção do cafeeiro e qualidade da bebida do café. As variáveis analisadas no experimento de fertilidade do solo foram; pH, P, K, Ca, Mg, soma de bases, H+Al, CTC, V % e matéria orgânica; a avaliação do estado nutricional constou das análises das variáveis N e K foliar. Os atributos de fertilidade do solo (pH e V %), foram mais elevados nos tratamentos 6,4%, 7% e 35,4%, especialmente nas camadas superficiais (0-2 e 2-7 cm) e o teor de matéria orgânica na camada de 0-2 cm, proporcionados pelas seringueiras. Menores teores de K do solo ocorreram nos tratamentos 7% e 35,4%, devido a absorção pelas seringueiras. A característica de CTC elevada do solo não foi modificada pelos tratamentos. Os teores foliares de N e K do cafeeiro a pleno sol alcançaram valores mais elevados e mais baixos, respectivamente, do que aqueles dos cafeeiros à sombra. Os cafeeiros sob 45% de irradiância mantiveram estado nutricional adequado em relação aos teores foliares de N e K.
Coffee production is an important activity in the economy of Brazil, first world producer and exporter. Coffee trees present biennial production cycles, with oscillation accentuated due to the climatic conditions and the production system in monocrop under full natural radiation. Studies involving the evaluation of nutritional status of coffee in agroforestry systems are scarce, what difficult the fertilization recommendations for this conditions. The objective of the this study was of getting a better understanding of the soil fertility and nutritional status, specially for the N and K content, of coffee trees under agroforestry system and monocrop. The research was conducted from March 2006 to May 2008, at the experimental field of the Plant Production Department of the Escola Superior de Agricultura Luiz de Queiroz of the Universidade de São Paulo (ESALQ/USP), in Piracicaba SP (220 42 20 S, 470 37 22 W) at the altitude of 565 m. The experiment was composed of rubber trees, clone PB 235, planted in December 1991, in the spacing of 8.0 x 2.5 m and coffee trees cv. Obatã IAC 1669-20, planted in January 2002, in the spacing of 3.4 x 0.9 m, under different shading conditions: undertorey or interfacing the rubber trees and in monocrop. The experimental design was completely randomized with four replications. The soil fertility experiment had six treatments, done by the different radiation regimes reaching the soil surface: 1) 6.4%; 2) 7%; 3) 35.4%; 4) 47.5%; 5) 60.9%; 6) 64.9%. The coffee nutritional status, in terms of the N and K leaf content had four treatments, done by the different radiation regime reaching the coffee canopy: 1) 35%; 2) 45%; 3) 90%; 4) 100%. Additionally, the study involved the evaluation of the litter deposition and decomposition rates, the soil organic matter fractions, coffee trees growth, its specific leaf area and anatomy, beans maturation, coffee yield and beverage quality. The variable under analysis in the soil fertility experiment were; pH, P, K, Ca, Mg, bases sum, H+Al, CTC, V % and organic matter; in the nutritional status were the N and K leaf content. The soil fertility attributes of pH and V % were improved in the treatments 6.4%, 7% e 35.4%, specially in the upper soils layers (0-2 e 2-7 cm) and organic matter content in the top soil layer (0-2 cm), due to the effect of the rubber trees. Lower K contents in the soil occurred in the treatments 7% e 35.4%, due to the rubber root uptake. The natural high CTC of the soil was not modified by treatments. N and K leaf content of coffee trees under full natural radiation (monocrop) reached the highest and lowest levels, respectively, in comparison with coffee trees under shade. Coffee at 45% of natural radiation maintained appropriate nutritional status in terms of N and K leaf content.

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In the first chapter the objective was to evaluate in laboratory the allelopathic effect of the aqueous extract of ingá leaves on germination, initial development and antioxidant activity of maize seedlings and in the second chapter the objective was to evaluate in greenhouse the allelopathic effect of the ingá on the emergency, initial growth and antioxidant response of corn seedlings. For the allelopathic effect on germination, we analyzed the percentage of germination, germination speed index, mean germination time, frequency and synchronization of the germination of the maize seeds exposed to the different proportions of the aqueous extract of the dried leaves of ingá. For the effect on the initial development, we analyzed the weight of the dry mass and the average length of the roots and aerial parts of the maize seedlings. The enzymes involved in oxidative stress, Superoxide dismutase, Catalase and Peroxidase, as well as lipid peroxidation, measured by the levels of malondialdehyde (MDA), were also quantified. For the greenhouse emergency test the treatments were also constituted by the different proportions of the aqueous extract of ingá, being evaluated the percentage of emergency, average time of emergency, index of emergency speed, synchronization and relative frequency. In the initial greenhouse growth test, a control was obtained and the treatment two that received ground cover with dry leaves of ingá, evaluating the aerial part dry mass, root dry mass, average length of aerial part and length root mean. For the evaluation of oxidative stress on initial growth, enzymes, superoxide dismutase, peroxidase and catalase, besides lipid peroxidation by malondialdehyde levels were quantified. The aqueous extract of the ingá leaves did not interfere in the germination variables of the corn, however, caused inhibition of root mean length, inhibited root and shoot catalase activity and increased root MDA contents. There were no statistical differences between treatments for the variables evaluated in the emergence and initial growth of corn seedlings in greenhouse. However, we observed that there was greater expression of catalase in both root and aerial part and lower lipid peroxidation in the aerial part of the seedlings submitted to treatment two. In this way we propose that the consortium among the species in Saf's is viable.
A presente dissertação foi dividida em dois capítulos. No primeiro o objetivo foi avaliar em laboratório o efeito alelopático do extrato aquoso das folhas de ingá, sobre germinação, desenvolvimento inicial e atividade antioxidante de plântulas de milho. No segundo capítulo o objetivo foi avaliar em casa de vegetação o efeito alelopático do ingá sobre a emergência, crescimento inicial e resposta antioxidante de plântulas de milho. Para o efeito alelopático sobre a germinação, analisou-se a porcentagem de germinação, índice de velocidade de germinação, tempo médio de germinação, frequência e sincronização da germinação das sementes de milho expostas as diferentes proporções do extrato aquoso das folhas secas de ingá. Para o efeito sobre o desenvolvimento inicial, analisamos o peso de massa seca e o comprimento médio de raízes e partes aéreas das plântulas de milho. Também foi quantificado a atividade das enzimas envolvidas no estresse oxidativo, superóxido dismutase, catalase e peroxidase, além da peroxidação lipídica, medida pelos teores de malondialdeido. Para o teste de emergência em casa de vegetação os tratamentos também foram constituídos pelas diferentes proporções do extrato aquoso de ingá, sendo avaliada a porcentagem de emergência, tempo médio de emergência, índice de velocidade de emergência, sincronização e frequência relativa. No teste de crescimento inicial em casa de vegetação foram obtidos uma testemunha e o tratamento dois que recebeu cobertura do solo com pó das folhas secas de ingá, avaliando a massa seca de parte aérea, massa seca de raiz, comprimento médio de parte aérea e comprimento médio de raiz. Para avaliação do estresse oxidativo sobre crescimento inicial foram quantificadas as enzimas, superóxido dismutase, peroxidase e catalase, além da peroxidação lipídica pelos níveis de malondialdeido. Em laboratório o extrato aquoso das folhas de ingá não interferiu nas variáveis de germinação do milho, no entanto, causou inibição do comprimento médio das raízes, inibição da atividade da catalase na raiz e parte aérea e aumentou os teores de MDA radicular. Em casa de vegetação não houve diferenças estatísticas entre os tratamentos para as variáveis avaliadas na emergência e crescimento inicial das plântulas de milho. No entanto, registramos que houve maior expressão da catalase tanto em raiz como em parte aérea e menor peroxidação lipídica na parte aérea das plântulas submetidas ao tratamento dois. Apesar de ser registrado efeito alelopático prejudicial em laboratório, o extrato não prejudicou o desenvolvimento das plântulas de milho em casa de vegetação. Sendo assim, propomos que o consórcio entre as espécies em SAFs é viável.

A prototype agroforestry system, which combined the low-input features and environmental benefits of the traditional Indonesian multi-species 'jungle rubber' system with high yielding rubber clones developed in monoculture plantations, was tested under on-farm conditions. Secondary forest was allowed to regenerate between weeded rows of clonal rubber. Clonal rubber establishment was studied, and the interactions between it, secondary forest species and farmer management were investigated using a combination of researcher- and farmermanaged weeding trials. In one trial, alteration of below-ground resources (using root barriers and trenches to create three soil volumes) did not affect above or below-ground growth of clonal rubber, although weeding significantly increased stem diameter and volume. It was concluded that secondary forest regrowth interfered with resource capture at the level of individual roots; interference was not due to depletion of total available resources. Shoot:root ratios and ratios of horizontally- to vertically-oriented proximal roots were not affected by weeding. Growth of clonal rubber in N-fertilised plots, in the presence of weeds, was significantly greater than in corresponding unfertilised plots, indicating that N-addition may overcome some negative effects of competition in the system. However, a bioassay of nutrient limitation showed no significant differences in root biomass or root-length density, for either rubber or weed rootingrowth into soil cores enriched with various nutrients. The second researcher-managed trial, on steep slopes, showed that the survival rate of clonal rubber was 33% higher than that of the 'seedling' rubber variety traditionally used, and that mean stem height and diameter of clonal rubber trees were significantly greater than those of seedling rubber, 21 months after planting. Damage to trees by banded leaf monkeys (Presbytis melalophos nobilis) and feral pigs (Sus barbatus) was severe, unexpected, and greater for seedling than for clonal rubber. For undamaged trees, weeding frequency within the rubber-tree row had no significant effect, indicating that the major influence on rubber tree growth was interference from secondary forest regrowth between rows, operating both aboveand below-ground. In a farmer-managed, trial, vertebrate pest damage was the major influence on clonal rubber establishment, explaining almost 70% of the variation in rubber growth. The amount of labour invested in weeding was positively correlated with rubber growth. However, fanners generally decided to completely cut back the secondary forest regrowth between rows of rubber trees, including potentially valuable trees, rather than weeding within the rows and selectively pruning inter-row trees. Farmers considered that the inter-row vegetation may harbour vertebrate pests and compete with the clonal rubber, and they had access to fruits, firewood and non-timber forest products on other land. Thus, contrary to expectations, when offered clonal germplasm, these 'progressive' farmers opted to use plantation methods to protect what they considered a valuable asset suited to monoculture, rather than maintain the traditional multispecies strategy they use with local germplasm. Thus, although clonal rubber can technically be established in a 'jungle rubber'-like system (albeit with lower growth rates than achieved in plantations), not all farmers may be prepared to adopt this type of system.

Mestrado em Gestão de Sistemas de Informação
A necessidade de gestão agroflorestal é cada vez mais real. A exploração de propriedades, agrícolas ou florestais, carece de planeamento e metodologia. Os sistemas de informação têm vindo a ganhar relevo e importância na georreferenciação e apoio à tomada de decisão. Da recolha, arquivo e análise de dados geográficos, características do solo e clima, fatores sócio económicos e de gestão, podem criar-se sistemas de suporte à decisão que promovam a utilização da terra de uma forma sustentável e rentável. Este trabalho estudou a componente tecnológica de um Sistema de Informação orientado à gestão de recursos agroflorestais, propondo e integrando as tecnologias selecionadas. Implementado em 4 fases distintas, permite registar os dados das propriedades, realizar estudos de casos e propor metodologias para a sua exploração e promoção, trazendo valor acrescentado para todos os stakeholders envolvidos.
The need for agroforestry management is increasingly real. The exploration of properties, agricultural or forestry, lacks planning and methodology. Information systems have been gaining relevance and importance in georeferencing and in supporting decision making. The collection, storage and analysis of spatial data, soil and climatic characteristics, socio economic and management factors, can create decision support systems that promote the use of land in a sustainable and profitable way. This work studied the technological component of an Information System oriented to agroforestry resource management, proposing and integrating the selected technologies. Implemented in four phases, allows the data register of properties, conduct study-cases and propose methodologies for their exploration and promotion, bringing added value to all stakeholders involved.

Resource capture and utilisation were studied in two agroforestry systems at the International Centre for Research in Agroforestry (ICRAF) Research Station at Machakos, Kenya. The agroforestry systems examined contained two contrasting tree species, leucaena (Leucaena leucocephala (Lam.) de wit) and grevillea (Grevillea robusta), and the C3 and C4 crops, cowpea (Vigna unguiculata) and maize (Zea mays, Katumani composite). The leucaena-based trial was established in November 1989 and the trees were grown with ten maize crop rows on either side of a pruned hedgerow (HM) or unpruned tree row (LM). A sole maize control (SM) was also grown. Paired sets of treatments were irrigated to eliminate below-ground competition for water (HMI, LMI and SMI respectively). Interception of photosynthetically active radiation (PAR) by leucaena and maize was measured on a row-wise basis in all treatments at 7-10 day intervals using a sunfleck ceptometer. Sap flux was measured for the maize and both pruned and unpruned leucaena using heat balance gauges. Results are presented for the 1992 April-July rainy season. Total PAR interception was 30 % greater in LM and LMI than in the SM and SMI sole maize treatments. However, little more than 30 % of the light intercepted by the LM and LMI systems was captured by the crop component, and competition for light alone reduced maize yields by over 30 %. Total water uptake by the LM leucaena and maize comprised 60 % of the seasonal rainfall (237 mm) as compared to 30 % for sole maize. However, as for light interception, only 30 % of the water transpired in LM was used by the intercropped maize, and competition from the trees for soil water reduced maize yields at distances of over 6 m from the leucaena. The leucaena was more effective at resource capture, yet less efficient in resource utilisation since it exhibited a lower dry matter:radiation quotient and a lower transpired water:dry matter ratio than maize. Thus the leucaena in the agroforestry systems captured more of the resources that could have been used more effectively by the maize, causing the performance of the mixture to be sub-optimal; these results suggest that the two components would be best grown separately. Intensive monitoring of resource capture and use by trees and crops was subsequently transferred to the Complementarity In Resource Use on Sloping land trial (CIRUS). Although it had been intended to study both trials during the long rains of 1993, the leucaena trees were almost completely defoliated by psyllid (Heteropsylla cubana) infestation shortly before the onset of the rains: in subsequent seasons, CIRUS was studied in preference to the leucaena trial as the trees had only partially recovered. CIRUS was designed to investigate the effects of competition and the extent of complementarity between grevillea and associated crops using the following treatments; sole crops (Cg) of cowpea during the short rains and maize during the long rains, dispersed-planted trees with (CTd) and without crops (Td), and across (CTa) or on-contour-planted (CTc) tree rows with crops. Light interception and water use were monitored using a similar measurement regime to that employed in the leucaena trial. Results are presented for the 199213 and 1993/4 short rainy seasons; the failure of the 1993 long rains forced the abandonment of experimental measurements during this season. Light interception by the Td and CTd grevillea increased greatly between the two short rainy seasons. Thus, total seasonal interception of PAR was three times greater in sole cowpea than in sole grevillea during the 1992/3 short rains, but by the following short rainy season was over 50 % greater in the grevillea than in the cowpea. Cumulative interception of PAR by the CTd grevillea and cowpea combined was more than twice that of the sole cowpea and over 40 % greater than that for sole grevillea during the 1993/4 short rains. Experiments involving artificially imposed shade showed that there was no reduction in total above-ground dry matter production in cowpea until 75 % shading was imposed. To quantify the degree of below-ground complementarity in water use between grevillea and cowpea, sap flux was measured using heat balance gauges attached to the stems of young grevillea (10-18 months old), both before and after excavating the crop rooting zone (upper 60 cm of soil) around the stem base. The crop rooting zone was removed to establish the capability of the grevillea to extract water from deeper horizons. After excavation, the trees maintained sap fluxes of up to 85 % of the unexcavated values. During both short rains, soil evaporation was by far the largest component of the water balance in all treatments. However, continued extraction of water by the trees during the dry season greatly increased resource capture~ thus total water uptake was three times greater for the sole trees than for the sole crop when dry season water use was included. During the 1993/4 short rains, water use was greatest in the CTd treatment, in which 25 % of the total seasonal rainfall was transpired by the trees and crops. Although transpiration by the CTd trees exceeded interception losses, the latter may have had a greater effect on crop growth by reducing the total quantity of water available within the system. The existence of below-ground complementarity and the shade tolerance of the cowpea suggest that deep-rooted tree species and certain C3 crops may be combined successfully in the semi-arid tropics, but the sensitivity of crop yield to any reduction in water availability within the system demonstrates the need for caution when implementing such systems. The results obtained are discussed in relation to previous research on intercropping and agroforestry and their implications for the successful adoption of agroforestry systems in the semi-arid tropics.

The aim of the study was to establish whether clones could be selected for single or multipurpose products by conducting studies involving the evaluation of phenotypic characteristics and their influence on biomass production using Sesbania sesban (L.) provenances and clones. The study initially examined the extent of genetic variation in phenotypic characteristics and biomass production in S. sesban provenances at Maseno, in Kenya. The study showed that significant differences existed between provenances and that it was possible to select of outstanding individual trees in the best provenances for testing on different sites as clones. Significant allometric relationships were established between dry mass, and tree dimensions for the different tree components. Stem diameter at 0.15 m provided a reliable estimation of biomass in the provenances. The provenance repeatabilities (0.31-0.41) and potential genetic gain (40%) highlight the expected returns due to selection. Plant growth analysis results helped in understanding the growth of young S. sesban clones in the field at Maseno, particularly the distribution of biomass into components. Clones performed similarly in the initial stages of growth and differences were only detected when competition set in. Clone net assimilation ratios were found to be sensitive to moisture stress. Leaf area was found to be the major determinant of clonal differences and was a good indicator of plant growth and productivity. The results from the genetic variation and productivity study of S. sesban clones grown at Maseno, Kisii and Machakos revealed a differential response of the clones to different environmental conditions. Although there was lack of genotype by environmental interaction among clones, biomass production was higher at Maseno and Kisii than Machakos. S. sesban clones differed greatly in absolute biomass but showed similar percentage distribution of dry mass among the different tree components with branches being a major preferred sink.