Dissertations / Theses: 'Forests and forestry Soil surveys'

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Fabian, Christopher J. "Application of a digital terrain model for forrest land classification and soil survey." Diss., Columbia, Mo. : University of Missouri-Columbia, 2004. http://hdl.handle.net/10355/4107.

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Thesis (M.S.) University of Missouri-Columbia, 2004.
The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Title from title screen of research.pdf file viewed on (June 30, 2006). Vita. Includes bibliographical references.

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Habermann, Birgit. "Ways of knowing of farmers and scientists : tree and soil management in the Ethiopian Highlands." Thesis, University of Sussex, 2014. http://sro.sussex.ac.uk/id/eprint/49648/.

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The Ethiopian Highlands have been studied extensively, hosting a large amount of research for development projects in agriculture and forestry over several decades. The encounters in these projects were also encounters of different ways of knowing that were negotiated by the actors meeting in the space provided by the projects. This research explores these encounters and the social worlds they are embedded in, drawing on actor-oriented approaches as well as theories of narratives and framing. Ways of knowing and citizen epistemologies are taken as a lens to understand the role of identities in knowledge production and use. The two case studies were agroforestry research projects in the Ethiopian Highlands. The research followed a range of qualitative and ethnographic research methods. Different types of farmers and scientists meet in the case studies. I recognise that they all have individual agency, nevertheless I use the terms ‘scientist' and ‘farmer' in this thesis. I use the terms to describe certain groups of actors who all draw on different ways of knowing, and different value systems, when interacting with each other and their environment. The results indicate that the importance of social worlds at different scales and the contexts of research projects tend to be underestimated. In spite of good intentions scientific methodologies, terminologies and narratives tend to dominate. Scientists in the case studies acknowledged the existence of farmers' ‘indigenous' knowledge, but they determined the value of knowledge by its scientific applicability and the replicability of experiments. Research systems force the scientists into a certain modus operandi with limited possibilities to experiment and to respond to the complexities and diversities of people's social worlds. Farmers in the case studies preferred observation from their parents, observing from others or the environment as a way of learning and gaining knowledge. Depending on their personalities and their life histories they also relied on alternative ways of knowing rooted in spirituality, emotions and memories. Powerful influences on ways of knowing resulted from the way languages and authority had been used. These often led to the exclusion of marginalised community members from access to knowledge and technologies. Unfortunately, common narratives prevailed in the case studies, and alternative ways of knowing were often marginalised. By acknowledging different ways of knowing and the importance of different social worlds and different ways of doing research, both scientists and farmers could benefit and develop more sustainable pathways for agricultural and forestry land use.

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Newmann, Sarah McCarthy. "Plant-soil feedbacks in temperate and tropical forests." Diss., Connect to online resource - MSU authorized users, 2008.

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Thesis (Ph.D.)--Michigan State University. Dept. of Forestry Program in Ecology, Evolutionary Biology and Behavior, 2008.
Title from PDF t.p. (viewed on July 13, 2009) Includes bibliographical references (p. 170-184). Also issued in print.

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Amichev, Beyhan Y. "Comparison of Techniques for Estimation of Forest Soil Carbon." Thesis, Virginia Tech, 2003. http://hdl.handle.net/10919/9915.

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Soil organic carbon represents the largest constituent of the global C pool and carbon budgets are studied by researchers and modelers in C cycling, global climate change, and soil quality studies. Pedon and soil interpretation record databases are used with soil and ecological maps to estimate regional SOC even though these databases are rarely complete for surface litter and mineral subsurface horizons. The first main objective of the project is to improve the ability to produce soil organic carbon estimates from existing spatial soils datasets, such as STATSGO. All records in the STATSGO Layer table that were incomplete or appeared to be incorrectly filled with a null or zero value were considered invalid. Data sorting procedures and texture lookup tables were used to identify exiting correct (valid) data entries that were used to substitute invalid records. STATSGO soil property data were grouped by soil order, MLRA, layer number, and texture to produce replacement values for all invalid data used to calculate mass SOC. Grouping criteria was specific to each variable and was based on texture designations. The resulting filled and unfilled tables were used with procedures assuming Normal and Lognormal distribution of parameters in order to analyze variation of mass SOC estimates caused by using different computation techniques. We estimated mass SOC to 2 m in Maine and Minnesota using filled and unfilled STATSGO data tables. Up to 54% of the records in Maine and up to 80% of the records in Minnesota contained null or zero values (mostly in fields related to rock fragments) that were replaced. After filling, the database resulted in 1.5 times higher area-weighted SOC. SOC calculated using the Normal distribution assumption were 1.2 to 1.5 times higher than those using the Lognormal transformation. SOC maps using the filled tables had more logical geographic SOC distribution than those using unfilled tables. The USDA Forest Service collects and maintains detailed inventory data for the condition and trends of all forested lands in the United States. A wide range of researchers and landowners use the resulting Forest Inventory and Analysis (FIA) database for analytical and decision making tasks. FIA data is available to the public in transformed or aggregate format in order to ensure confidentiality of data suppliers. The second main objective of this project was to compute SOC (kg m-2) results by FIA forest type and forest type group for three depth categories (25 cm, 1 m, and 2 m) at a regional scale for the 48 contiguous United States. There were four sets of results derived from the filled STATSGO and FIA datasets for each depth class by region: (1) SOC computed by the Lognormal distribution approach for (1a) all soil orders, (1b) without Histosols; and (2) SOC computed by the Normal distribution approach for (2a) all soil orders, (2b) without Histosols. Two spatial forest cover datasets were relevant to this project, FIA and AVHRR. We investigated the effects of FIA inventory data masking for Maine and Minnesota, such as plot coordinates rounding to the nearest 100 arc-second, and the use of 1 km resolution satellite-derived forest cover classes from AVHRR data, on SOC estimates to 2 m by forest type group. SOC estimates by soil mapping unit were derived from fixed STATSGO database tables and were computed by the Lognormal distribution approach including all soil orders. The methods in this study can be used for a variety of ecological and resource inventory assessments and the automated procedures can be easily updated and improved for future uses. The procedures in this study point out areas that could benefit the most during future revisions of STATSGO. The resulting SOC maps are dynamic and can be rapidly redrawn using GIS whenever STATSGO spatial or tabular data undergo updating. Use of pedon data to define representative values for all properties in all STATSGO layers and correlation of STATSGO layers to soil horizons will lead to vast improvement of the STATSGO Layer table and promote its use for mass SOC estimation over large regions.
Master of Science

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Hart, Tim. "Stem profile equations for several commercially important timber species in Wisconsin /." Link to full text, 2009. http://epapers.uwsp.edu/thesis/2009/Hart.pdf.

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Thesis (M.S.)--University of Wisconsin--Stevens Point, 2009.
Submitted in partial fulfillment of the requirements of the degree Master of Science in Natural Resources (Forestry), College of Natural Resources. Includes bibliographical references (leaves 82-87).

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Stum, Alexander Knell. "Random Forests Applied as a Soil Spatial Predictive Model in Arid Utah." DigitalCommons@USU, 2010. https://digitalcommons.usu.edu/etd/736.

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Initial soil surveys are incomplete for large tracts of public land in the western USA. Digital soil mapping offers a quantitative approach as an alternative to traditional soil mapping. I sought to predict soil classes across an arid to semiarid watershed of western Utah by applying random forests (RF) and using environmental covariates derived from Landsat 7 Enhanced Thematic Mapper Plus (ETM+) and digital elevation models (DEM). Random forests are similar to classification and regression trees (CART). However, RF is doubly random. Many (e.g., 500) weak trees are grown (trained) independently because each tree is trained with a new randomly selected bootstrap sample, and a random subset of variables is used to split each node. To train and validate the RF trees, 561 soil descriptions were made in the field. An additional 111 points were added by case-based reasoning using aerial photo interpretation. As RF makes classification decisions from the mode of many independently grown trees, model uncertainty can be derived. The overall out of the bag (OOB) error was lower without weighting of classes; weighting increased the overall OOB error and the resulting output did not reflect soil-landscape relationships observed in the field. The final RF model had an OOB error of 55.2% and predicted soils on landforms consistent with soil-landscape relationships. The OOB error for individual classes typically decreased with increasing class size. In addition to the final classification, I determined the second and third most likely classification, model confidence, and the hypothetical extent of individual classes. Pixels that had high possibility of belonging to multiple soil classes were aggregated using a minimum confidence value based on limiting soil features, which is an effective and objective method of determining membership in soil map unit associations and complexes mapped at the 1:24,000 scale. Variables derived from both DEM and Landsat 7 ETM+ sources were important for predicting soil classes based on Gini and standard measures of variable importance and OOB errors from groves grown with exclusively DEM- or Landsat-derived data. Random forests was a powerful predictor of soil classes and produced outputs that facilitated further understanding of soil-landscape relationships.

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Brown, Ian K. "Wisconsin statewide urban forest assessment : development and implementation /." Link to full text, 2007. http://epapers.uwsp.edu/thesis/2007/Brown.pdf.

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Holmström, Hampus. "Data acquisition for forestry planning by remote sensing based sample plot imputation /." Umeå : Swedish Univ. of Agricultural Sciences (Sveriges lantbruksuniv.), 2001. http://epsilon.slu.se/avh/2001/91-576-6086-7.pdf.

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Schelling, Lisa R. "Soil seed banks in mixed oak forests in Southeastern Ohio." Ohio : Ohio University, 2006. http://www.ohiolink.edu/etd/view.cgi?ohiou1141850222.

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Abdo, Maria Teresa Vilela Nogueira [UNESP]. "Caracterização da vegetação arbórea e atributos do solo da Reserva Biológica de Pindorama, SP." Universidade Estadual Paulista (UNESP), 2009. http://hdl.handle.net/11449/105249.

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O Pólo Regional de Desenvolvimento Tecnológico do Agronegócio da Região Centro Norte em Pindorama, SP, com 532,8 ha possui quatro fragmentos florestais distribuídos em 120 ha classificados como floresta tropical estacional semidecidual do bioma Mata Atlântica. Transformados em Reserva Biológica (Lei Estadual nº 4960/86) detêm grande diversidade das espécies de ocorrência regional. O presente trabalho teve por objetivo caracterizar a vegetação arbórea de dois fragmentos pertencentes à Reserva Biológica de Pindorama - SP e sua possível variação florística e estrutural decorrente dos atributos de solos, de relevo, distância da borda e infestação da área. Foram demarcados dois transectos com parcelas sequenciais de 20 m x 20 m em fragmentos e solos distintos. Foi realizado um levantamento planialtimétrico usando as variáveis: declividade, altitude e disposição das parcelas ao longo do transecto. Foi sorteado um quadrante de 10 m x 10 m por parcela, para realizar as avaliações de granulometria e fertilidade do solo, bem como de identificação e classificação dos indivíduos arbóreos com diâmetro a altura do peito (DAP) ≥ 5,0 cm e dos seguintes descritores fitossociológicos: frequência, dominância e densidades relativas e absolutas, valor de importância (VI), Índice de Diversidade de Shannon (H`), Coeficiente de Equabilidade de Pielou (J) e o Índice de Similaridade de Jaccard (ISJ) entre as duas áreas. Em cada parcela de 20 m x 20 m foi avaliado o grau de infestação por plantas invasoras, a altura, o DAP, a área basal, e o distanciamento da borda das quatro maiores árvores. A caracterização da vegetação arbórea foi feita com o uso de análises estatísticas multivariadas dos dados obtidos. O Índice de Diversidade de Shannon (H’) calculado foi 3,38 para as duas áreas e se encontra dentro da média para fragmentos de...
The Pólo Regional Centro Norte in Pindorama, SP, has a 120 hectares area constituted of forest remainders transformed into Biological Reserve by the law nº 4960/86 since a great diversity of regional occurrence species was withhold. These forest remainders are classified as seasonal semi-deciduous tropical forest of the Atlantic Forest biome. This work aimed carry out a phytosociological survey of two toposequences in different remainders and its possible soil attributes due variation and relief. To such work two transects were demarcated with sequential parcels of 20 m x 20 m. A topographic survey was carried out using the following variables: slope, height and localization of the plots throughout the profile. A quadrant of 10 m x 10 m was chosen randomly in each parcel and in its area an evaluation of the physical and chemical soil attributes using samples in the 0-20 cm depth composed of 20 sub-samples. In this quadrant the individuals with breast height diameter (DBH) ≥ 5,0 cm were identified, marked, classified and their phytosociology describers calculated: relative and absolute frequency and densities, value of importance (VI), Shannon Diversity Index (H `), Equability (J) and the Jaccard Similarity Index (ISJ) between the two areas. For each parcel the degree of weeds was evaluated adopting ten classes according the infestation percentage varying from null to very high. The hierarchic grouping test based on the soil physical and chemical attributes allowed a division in five groups of parcels. For each group the average values of each characteristic were determined, as well as recalculated the diversity species index, equability and the similarity between the groups index. It could be concluded that the hierarchic method grouping analysis showed efficient to separate groups of phytosociology sampling parcels in seasonal semi-deciduous tropical forest when it was ... (Complete abstract click electronic access below)

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Abdo, Maria Teresa Vilela Nogueira. "Caracterização da vegetação arbórea e atributos do solo da Reserva Biológica de Pindorama, SP /." Jaboticabal : [s.n.], 2009. http://hdl.handle.net/11449/105249.

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Resumo: O Pólo Regional de Desenvolvimento Tecnológico do Agronegócio da Região Centro Norte em Pindorama, SP, com 532,8 ha possui quatro fragmentos florestais distribuídos em 120 ha classificados como floresta tropical estacional semidecidual do bioma Mata Atlântica. Transformados em Reserva Biológica (Lei Estadual nº 4960/86) detêm grande diversidade das espécies de ocorrência regional. O presente trabalho teve por objetivo caracterizar a vegetação arbórea de dois fragmentos pertencentes à Reserva Biológica de Pindorama - SP e sua possível variação florística e estrutural decorrente dos atributos de solos, de relevo, distância da borda e infestação da área. Foram demarcados dois transectos com parcelas sequenciais de 20 m x 20 m em fragmentos e solos distintos. Foi realizado um levantamento planialtimétrico usando as variáveis: declividade, altitude e disposição das parcelas ao longo do transecto. Foi sorteado um quadrante de 10 m x 10 m por parcela, para realizar as avaliações de granulometria e fertilidade do solo, bem como de identificação e classificação dos indivíduos arbóreos com diâmetro a altura do peito (DAP) ≥ 5,0 cm e dos seguintes descritores fitossociológicos: frequência, dominância e densidades relativas e absolutas, valor de importância (VI), Índice de Diversidade de Shannon (H'), Coeficiente de Equabilidade de Pielou (J) e o Índice de Similaridade de Jaccard (ISJ) entre as duas áreas. Em cada parcela de 20 m x 20 m foi avaliado o grau de infestação por plantas invasoras, a altura, o DAP, a área basal, e o distanciamento da borda das quatro maiores árvores. A caracterização da vegetação arbórea foi feita com o uso de análises estatísticas multivariadas dos dados obtidos. O Índice de Diversidade de Shannon (H') calculado foi 3,38 para as duas áreas e se encontra dentro da média para fragmentos de ... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: The Pólo Regional Centro Norte in Pindorama, SP, has a 120 hectares area constituted of forest remainders transformed into Biological Reserve by the law nº 4960/86 since a great diversity of regional occurrence species was withhold. These forest remainders are classified as seasonal semi-deciduous tropical forest of the Atlantic Forest biome. This work aimed carry out a phytosociological survey of two toposequences in different remainders and its possible soil attributes due variation and relief. To such work two transects were demarcated with sequential parcels of 20 m x 20 m. A topographic survey was carried out using the following variables: slope, height and localization of the plots throughout the profile. A quadrant of 10 m x 10 m was chosen randomly in each parcel and in its area an evaluation of the physical and chemical soil attributes using samples in the 0-20 cm depth composed of 20 sub-samples. In this quadrant the individuals with breast height diameter (DBH) ≥ 5,0 cm were identified, marked, classified and their phytosociology describers calculated: relative and absolute frequency and densities, value of importance (VI), Shannon Diversity Index (H '), Equability (J) and the Jaccard Similarity Index (ISJ) between the two areas. For each parcel the degree of weeds was evaluated adopting ten classes according the infestation percentage varying from null to very high. The hierarchic grouping test based on the soil physical and chemical attributes allowed a division in five groups of parcels. For each group the average values of each characteristic were determined, as well as recalculated the diversity species index, equability and the similarity between the groups index. It could be concluded that the hierarchic method grouping analysis showed efficient to separate groups of phytosociology sampling parcels in seasonal semi-deciduous tropical forest when it was ... (Complete abstract click electronic access below)
Orientador: Sergio Valiengo Valeri
Coorientador: Antônio Sérgio Ferraudo
Banca: Rinaldo César de Paula
Banca: Teresa Cristina Tarlé Pissarra
Banca: Sidney Rosa Vieira
Banca: Luiz Fernando Duarte de Moraes
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Latifah, Sitti. "Inventory and quality assessment of tropical rainforests in the Lore Lindu National Park (Sulawesi, Indonesia) /." Göttingen : Cuvillier, 2005. http://bvbr.bib-bvb.de:8991/F?func=service&doc_library=BVB01&doc_number=013215823&line_number=0001&func_code=DB_RECORDS&service_type=MEDIA.

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Chan, Wing-ho Michael. "Characteristics and genesis of soils in Hong Kong's Fung Shui woodlands." Hong Kong : University of Hong Kong, 2000. http://sunzi.lib.hku.hk/hkuto/record.jsp?B2275362X.

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Stow, Nicholas. "Effects of selection cutting on soil chemistry, plant community composition and structural features of northern hardwood forests." Thesis, University of Ottawa (Canada), 2003. http://hdl.handle.net/10393/28968.

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Selection-cutting is the preferred method of logging in northern hardwood forests, because it is thought to favor the regeneration of valuable, shade-tolerant trees, maximize long-term productivity, and increase the health, quality and economic value of residual trees. Claims have also been made for the ecological sustainability of selection cutting, in particular that it: (a) preserves soil fertility; (b) maintains natural canopy composition; (c) protects plant and animal habitat. I evaluated these claims by studying the effects of selection-cutting on several measures of soil fertility (Ca, Al, Ca/Al molar ratios, pH), canopy composition and tree regeneration, herbaceous layer composition, and structural features related to habitat quality (cavity trees, snags, coarse woody debris) in 55 stands ranging from newly cut to old-growth (not all data overlaps). I found that forest growth after selection-cutting depletes soil solution calcium and lowers soil solution Ca/Al molar ratios, posing a threat to long-term forest health and productivity, particularly at higher elevations and in sites on siliceous bedrock. I found that selection-cut stands dominated by red oak (Quercus rubra) are converting to sugar maple (Acer saccharum) stands, posing a threat to both canopy and herbaceous layer diversity. I found no lasting effects of selection-cutting on herbaceous layer composition, diversity or quality, but I found indirect threats from the conversion of red oak stands to sugar maple and from depletion of soil solution calcium. Finally, I found that current selection-cutting practices generally do not meet published targets for large trees, cavity trees, snags and coarse woody debris, but that they probably could meet those targets with minor changes to cutting practices. I conclude by discussing the implications of these results for the management of northern hardwood forests.

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McCarthy, Dawn R. "Belowground Carbon Processes in Managed Oak-Hickory Forests of Southeastern Ohio." Ohio University / OhioLINK, 2008. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1226451729.

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Bender, John Richard. "Identifying structural differences in mixed mesophytic and northern hardwood forests on the Monongahela National Forest using remote sensing data." Morgantown, W. Va. : [West Virginia University Libraries], 1999. http://etd.wvu.edu/templates/showETD.cfm?recnum=976.

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Thesis (M.A.)--West Virginia University, 1999.
Title from document title page. Document formatted into pages; contains viii, 55 p. : ill. (some col.), maps. Includes abstract. Includes bibliographical references (p. 44-48).

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Almond, Peter C. "Soils and geomorphology of a lowland rimu forest managed for sustainable timber production." Lincoln University, 1997. http://hdl.handle.net/10182/1782.

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Saltwater Forest is a Dacrydium cupressinum-dominated lowland forest covering 9000 ha in south Westland, South Island, New Zealand. Four thousand hectares is managed for sustainable production of indigenous timber. The aim of this study was to provide an integrated analysis of soils, soil-landform relationships, and soil-vegetation relationships at broad and detailed scales. The broad scale understandings provide a framework in which existing or future studies can be placed and the detailed studies elucidate sources of soil and forest variability. Glacial landforms dominate. They include late Pleistocene lateral, terminal and ablation moraines, and outwash aggradation and degradation terraces. Deposits and landforms from six glacial advances have been recognised ranging from latest Last (Otira) Glaciation to Penultimate (Waimea) Glaciation. The absolute ages of landforms were established by analysis of the thickness and soil stratigraphy of loess coverbeds, augmented with radiocarbon dating and phytolith and pollen analysis. In the prevailing high rainfall of Westland soil formation is rapid. The rate of loess accretion in Saltwater Forest (ca. 30 mm ka⁻¹) has been low enough that soil formation and loess accretion took place contemporaneously. Soils formed in this manner are known as upbuilding soils. The significant difference between upbuilding pedogenesis and pedogenesis in a topdown sense into an existing sediment body is that each subsoil increment of an upbuilding soil has experienced processes of all horizons above. In Saltwater Forest subsoils of upbuilding soils are strongly altered because they have experienced the extremely acid environment of the soil surface at some earlier time. Some soil chronosequence studies in Westland have included upbuilding soils formed in loess as the older members of the sequence. Rates and types of processes inferred from these soils should be reviewed because upbuilding is a different pedogenic pathway to topdown pedogenesis. Landform age and morphology were used as a primary stratification for a study of the soil pattern and nature of soil variability in the 4000 ha production area of Saltwater Forest. The age of landforms (> 14 ka) and rapid soil formation mean that soils are uniformly strongly weathered and leached. Soils include Humic Organic Soils, Perch-gley Podzols, Acid Gley Soils, Allophanic Brown Soils, and Orthic or Pan Podzols. The major influence on the nature of soils is site hydrology which is determined by macroscale features of landforms (slope, relief, drainage density), mesoscale effects related to position on landforms, and microscale influences determined by microtopography and individual tree effects. Much of the soil variability arises at microscales so that it is not possible to map areas of uniform soils at practical map scales. The distribution of soil variability across spatial scales, in relation to the intensity of forest management, dictates that it is most appropriate to map soil complexes with boundaries coinciding with landforms. Disturbance of canopy trees is an important agent in forest dynamics. The frequency of forest disturbance in the production area of Saltwater Forest varies in a systematic way among landforms in accord with changes in abundance of different soils. The frequency of forest turnover is highest on landforms with the greatest abundance of extremely poorly-drained Organic Soils. As the abundance of better-drained soils increases the frequency of forest turnover declines. Changes in turnover frequency are reflected in the mean size and density of canopy trees (Dacrydium cupressinum) among landforms. Terrace and ablation moraine landforms with the greatest abundance of extremely poorly-drained soils have on average the smallest trees growing most densely. The steep lateral moraines, characterised by well drained soils, have fewer, larger trees. The changes manifested at the landform scale are an integration of processes operating over much shorter range as a result of short-range soil variability. The systematic changes in forest structure and turnover frequency among landforms and soils have important implications for sustainable forest management.

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Luizao, Regina C. C. "Soil biological studies in contrasting types of vegetation in central Amazonian rain forests." Thesis, University of Stirling, 1994. http://hdl.handle.net/1893/2274.

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Studies were carried out in a lowland evergreen rain forest (LERF), on an ultisol, in the 'Reserva da Campina', 45 km north of Manaus, and in two facies of the highly distinct formation called heath forest, on spodosols. The spodosols had a layer of mor humus of thickness varying from nil in some parts in the smaller facies of heath forest (SHF) to 35 cm in the taller facies (THF). The overall aim was to investigate the forest soil biota and its role in nutrient turnover by comparing the SHF, THF and LERF. Microbial biomass, soil respiration and nitrogen transformation rates were measured in the three forest types in both wet and dry seasons. Field and laboratory fertilization experiments were made to investigate potential limiting nutrients for microorganisms and plants. The role of fine roots in decomposition and litter animal colonization was assessed in litter bag studies. SHF soils have a small microbial population with no net nitrification in any season. THF soils showed a variable microbial population adapted to high acidity, which immobilises nitrogen during the wet season, but which allows a net release during the dry season. LERF showed the most diverse population which causes mineralization and nitrification in both seasons. A bioassay with nutrient addition showed that the low pH, and nitrogen and sulphur supply were likely to be limiting nitrogen dynamics in all forest types, but especially in THF and LERF. The ingrowth bags showed that despite the lower values of fine root growth in the SHF (particularly when the white sand of the spodosol was used as the substrate), the roots showed in all plots an increased production with added calcium as carbonate or sulphate. In the decomposition bioassay to evaluate the role of roots in the nutrient turnover it was shown that in all forest types there was no effect of roots on the mass loss of Clitoria leaves but there was a significant effect on concentrations of some nutrients. In general, roots contributed to the accumulation of aluminium and iron and to a faster release and uptake of calcium, magnesium and zinc. A survey of the mycorrhizal associations in all forest types showed that both VAM and ECM fungi with some unknown VAM fungal species are common. VAM and ECM adaptation to low pH and high phenolic compounds in the soils may be important in the maintenance of these ecosystems.

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Sørensen, Rasmus. "Influence of topography and forestry on catchments : soil properties, runoff regime, and mercury outputs /." Uppsala : Department of Aquatic Sciences and Assessment, Swedish University of Agricultural Sciences, 2009. http://epsilon.slu.se/200985.pdf.

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Subburayalu, Sakthi Kumaran. "Application of machine learning for soil survey updates a case study in southeastern Ohio /." Columbus, Ohio : Ohio State University, 2008. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1199992659.

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Holmgren, Eva. "Forest commons in boreal Sweden : influences on forest condition, management and the local economy /." Umeå : Dept. of Forest Resource Management and Geomatics, Swedish University of Agricultural Sciences, 2006. http://epsilon.slu.se/10124692.pdf.

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Miesel, Jessica Rae. "Restoring Mixed-Conifer Forests with Fire and Mechanical Thinning: Effects on Soil Properties and Mature Conifer Foliage." Columbus, Ohio : Ohio State University, 2009. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1239375425.

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Kamwi, Jonathan Mutau. "The use of high-resolution satellite imagery in forest inventory : a case of Hans Kanyinga Community Forest - Namibia." Thesis, Link to the online version, 2007. http://hdl.handle.net/10019/650.

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McClain, Mark Stephen. "The forest composition and the pedology of the undisturbed soils in an old-growth virgin beech-maple forest in east-central Indiana." Virtual Press, 1985. http://liblink.bsu.edu/uhtbin/catkey/426369.

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The edaphic and pedologic factors of forest soils and their influence on the naturally occurring climax vegetation in an old-growht forest in east-central Indiana were examined. The northern portion of this woods is a virgin remnant of the presettlement forest that Braun (1950) described as the BeechMaple Forest Region. This remnant is best classified as a sugar maple-American beech-slippery elm association. The undisturbed soils found were the moderately well drained Glynwood soils (Aquic Hapludalfs, fine, illitic, mesic), the somewhat poorly drained Blount soils (Aeric Ochraqualfs, fine, illitic, mesic), the poorly drained Lenawee Variant soils (Typic Haplaquepts, fine, nonacid, mixed,mesic), and the very poorly drained Lenawee (taxajunct) soils (Mollic Haplaquepts, fine-loamy, nonacid, mixed, mesic). The seasonal high water table and internal soil drainage of the soils appear to influence the survival and importance of the dominant tree species. There were 25 tree species sampled.The three most important tree species were sugar maple (Acer saccharum, Marsh.), American beech (Fagus qrandifolia Ehrh.), and slippery elm (Ulmus rubra Muhl.)on the Blount, Glynwood, and Lenawee Variant soils. The fourth most important tree species was silver maple (Acer saccharinum L.) which was restricted to the lowland-depressional forest type (Lindsey and Schmelz, 1970) inclusion represented by the Lenawee (taxajunct) soils. The distribution of tree species occurring on each of the four soils was statistically examined at the 0.05 level of significance. Sugar maple had a significantly higher mean average basal area on the Glynwood soils; American beech had a significantly higher average number of trees on the Blount soils; and slippery elm had a significantly higher proportion of trees on the Glynwood soils.Ball State UniversityMuncie, IN 47306

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Holmgren, Eva. "Forest commons in boreal Sweden aims and outcomes on forest condition and rural development /." Umeå : Dept. of Forest Resource Management, Swedish University of Agricultural Sciences, 2009. http://epsilon.slu.se/200996.pdf.

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Jones, Philip Scott. "Restoration of Juniperus excelsa Bieb. and Olea europaea L. subsp. africana (Mill.) P.S. Green woodlands in Eritrea." Thesis, University of Stirling, 1991. http://hdl.handle.net/1893/25422.

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The research aim was to assess the vegetation and soils of the Rora /' Habab plateau, Eritrea and to develop methods of propagating the native tree species, juniper and olive. The research consisted of vegetation and soil surveys, interviews with local people, archival research, and experiments on propagation of olive and juniper. Junipers are now confined to the north of the plateau. Olives are more abundant in the north but have very few individuals in the centre, where there are many dead trees, or south. Soil erosion was ubiquitous and often severe. Soil morphology and nutrient status were related to vegetation, topography, land use, and erosion status, and varied greatly over short distances. Soil texture was coarser and most chemical factors (except total Ca and exchangeable Na) were lower in the south. Organic C, total N, exchangeable Ca, percent day, CEC and the sum of bases were higher in soils from grazed land than in cultivated fields. Germination of olive seeds was 92% when the endocarp was removed; stratification had little effect. Rooting of olive stem cuttings attained 76% under mist when parent plants were fertilised and cuttings were treated with rooting hormone. Germination for juniper was 56% after stratification at 5°C for 30 to 60 days. Juniper stem cuttings rooted in only one of three experiments, where rooting was 78% in a well ventilated, cool, low-mist environment. Olive seedlings which were fertilised and watered every 7, 14, or 21 days for two months, were taller, had lower root:shoot ratios and soil moisture than unfertilised plants. Fertilised seedlings watered every 28 days died. Root volume was less for plants watered every 21 days but watering interval had little effect on other variables in unfertilised seedlings. Ecological restoration is urgently required to rehabilitate the Rora plateau, which has Africa's most northerly remnant juniper / olive woodlands.

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Vleminckx, Jason. "The influence of soil factors and anthropogenic disturbances on tree species assemblages in central African forests." Doctoral thesis, Universite Libre de Bruxelles, 2015. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/209100.

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La diversité végétale exceptionnelle des forêts tropicales a toujours suscité une part d’incompréhension chez les scientifiques qui tentent de comprendre les processus à l’origine de cette diversité, ainsi que les mécanismes expliquant les changements spatiaux de composition spécifique. Une des clés de ce dernier mystère résiderait dans l’influence de la différentiation des niches écologiques, mais aussi de la dispersion limitée des graines et d’événements stochastiques (purement aléatoires et non prévisibles). La niche d’une espèce contraint celle-ci à s’établir dans un habitat présentant des gammes de conditions bien délimitées en termes de propriétés du sol (disponibilité en nutriments et toxicité de certains éléments) et d’intensité lumineuse. Par exemple, certaines espèces sont plus tolérantes à l’ombrage (espèces « sciaphiles ») que d’autres qui ne peuvent s’établir que dans des trouées forestières offrant suffisamment de lumière (espèces « héliophiles »). En Afrique centrale, les communautés d’arbres sont aujourd’hui en grande partie composées de ces espèces dites « héliophiles », alors que les ouvertures forestières naturelles sont rares. Il est fortement suspecté que la dominance de ces espèces soient la conséquence de trouées générées par l’homme qui, jusqu’au début de la période coloniale (vers 1900), occupait de vastes surfaces de forêt où il pratiquait l’agriculture sur brûlis. Cependant, peu d’études ont jusqu’à présent déterminé dans quelle mesure ces pratiques agricoles ont influencé la composition spécifique des forêts à l’échelle régionale comme à l’échelle locale.

L’objectif du présent travail est de faire la lumière sur l’impact de ces perturbations humaines mais aussi plus généralement sur l’influence relative de la niche écologique des espèces d’arbres par rapport à d’autres facteurs (dispersion limitée et facteurs stochastiques) sur leur distribution spatiale. Pour cela nous avons utilisé des données botaniques et environnementales provenant d’inventaires réalisés dans une forêt tropicale située en République Démocratique du Congo (quatre transects parallèles mesurant chacun 500 à 600 m de long), ainsi que des données similaires complémentées d’inventaires anthracologiques (estimation de la quantité de charbons de bois dans le sol, utilisée comme indicateur de feux passés d’origine anthropique) récoltées dans trois régions du sud du Cameroun (208 parcelles de 0,2 ha chacune).

Les données récoltées nous ont permis de mettre en évidence un impact significatif des propriétés physico-chimiques du sol sur la composition en espèces d’arbres. Plus précisément, nous avons pu constater une différence floristique marquée entre deux habitats très contrastés (sol sableux vs. sol argileux, Rép. Dém. Du Congo), et cela à une échelle spatiale locale (< 1 km²) où l’on pensait que de l’influence des facteurs stochastiques et de dispersion limitée étaient prépondérante. Mes analyses ont également démontré que cette différence était plus marquée pour les arbres de la canopée que pour les arbres des strates inférieures (« sous-canopée »), ce qui est sans doute lié au fait que de nombreux individus de la sous-canopée sont composés de juvéniles régénérant la canopée, parmi lesquels de nombreux arbres subissent une exclusion compétitive en cours (brouillant ainsi les signaux d’association espèce-habitat).

À une échelle spatiale beaucoup plus large cette fois (de 5 à 100 km, inventaires du Sud Cameroun), nous avons démontré que la diversité floristique était également influencée de manière significative par l’hétérogénéité spatiale de propriétés abiotiques du sol, notamment par les concentrations en (i) certains nutriments essentiels pouvant présenter des valeurs potentiellement limitantes (K, Mg, Ca et P) ainsi qu’en en (ii) élements pouvant être présents en quantités toxiques (Al et Mn). Cependant, alors que le signal environmental a été clairement détecté à l’échelle communautaire, seule les abondances d’une minorité d’espèces (< 15%) ont répondu significativement à la variation des conditions de sol. En outre, le nombre de réponses significatives a augmenté avec l’échelle d’observation ainsi qu’avec le degré d’hétérogénéité environnementale et/ou floristique. Pour mettre en évidence cet effet du sol, nous avons introduit une nouvelle approche permettant de tester la fraction d’une analyse de partition de variance correspondant à la part de variation floristique expliquée par l’effet de conditions édaphiques spatialement structurées (co-variation entre effets spatiaux et édaphiques), en combinant l’analyse de partition de variance avec des vecteurs propres de Moran (« Moran’s eigenvector maps ») et des translations toroïdales. Bien que cette méthode nous ait permis de déterminer si la fraction en question était significative, nous avons également mis en doute son interprétation habituelle suggérant que cette fraction représente une structure floristique directement induite par des structures spatiales de conditions de sol. Grâce à des simulations de populations végétales liées à des propriétés environnementales, nous avons mis en évidence que la valeur de la fraction étudiée ne semble finalement pas influencée par le degré de structuration spatiale des conditions environnementales, remettant donc en question l’utilité de l’analyse de partition de variance pour inférer des effets de processus écologiques sous-jacents sur la distribution spatiale des espèces d’arbres.

Enfin, les données floristiques et anthracologiques du Sud Cameroun ne nous ont pas permis de démontrer statistiquement l’hypothèse que les perturbations humaines passées sont en partie responsables de la dominance actuelle des espèces héliophiles. L’absence de corrélation significative entre l’abondance relative de ces espèces et la quantité de charbons de bois dans le sol peut s’expliquer par le fait que la majorité de ces charbons (60%) étaient trop vieux (1500 à 3000 ans) pour refléter des perturbations ayant influencé la diversité végétale présente.

Les conclusions générales de ma thèse de doctorat soutiennent que la niche écologique des espèces d’arbres des forêts tropicales africaines contribue de manière significative à déterminer leur assemblage dans l’espace, mais aussi que ces effets de niche dépendent fortement du contexte environnemental étudié ainsi que de l’échelle spatiale d’observation. Ce travail lève donc en partie un voile sur l’écologie des écosystèmes forestiers d’Afrique centrale qui restent largement méconnus par rapport à ceux d’Asie du Sud-Est et des régions néotropicales.

Doctorat en sciences, Spécialisation biologie végétale
info:eu-repo/semantics/nonPublished

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Ratliff, Tera Jean. "Nitrogen and Phosphorus Availability in Forests of Varying Ages in the Bartlett Experimental Forest White Mountains, New Hampshire." Miami University / OhioLINK, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=miami1343771632.

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Ndlovu, Nomzamo Bonisiwe. "Quantifying indigenous forest change in Dukuduku from 1960 to 2008 using GIS and remote sensing techniques to support sustainable forest management planning." Thesis, Stellenbosch : Stellenbosch University, 2013. http://hdl.handle.net/10019.1/85622.

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Thesis (MSc)--Stellenbosch University, 2013.
ENGLISH ABSTRACT: This study aimed to understand how Dukuduku Forest in Kwa-Zulu Natal has changed from 1960 to 2008 and whether the change in political regimes, during and post apartheid eras might have contributed to changes in forest extent. To achieve the aims, the following analyses were made: - Qualitative and quantitative spatial analyses of forest change; - Analyses of the correspondence of change with political changes in the country; - Assessment of perception of people living in the Dukuduku forest area. The Dukuduku land cover was mapped from aerial photos using ArcGIS 9.3 to determine whether or not there has been a significant change in the area from 1960-2008, in response to resource use pressures and to come up with the strategic sustainable management plan from the results found. Five aerial photographs were used to determine the changes in land cover from the year: 1960, 1970, 1992, 2005 and 2008. The Land cover types were classified into four classes, Indigenous Forests, Plantation Forests, Water Bodies and Other (open areas, cultivated land, and all the human disturbed and transformed land). The percentage of cover per class was compared across the years to determine overall change in land cover and the rate of change per year was also calculated. The results from the study showed that: - Natural Forest increased by 11% (700 ha), at the rate of 20.56 hectares per year between 1960 and 1992, which is the apartheid era. Between 1992 and 2008, the democratic era, the forest decreased by 34.4% (2472.31ha), at the rate of 168 hectares per year. - The Dukuduku forest community gains resources (timber and grass for construction, art, firewood, medicinal plants, grazing of livestock and food) from the forest. The people are willing to contribute in protecting the forest only if the governing authorities would include them in decisions made, as the NFA demands Participatory Forest Management, but which does not currently exist in Dukuduku.
AFRIKAANSE OPSOMMING: Hierdie studie ondersoek die verandering van die Dukuduku woud in Kwa-Zulu Natal vanaf 1960 tot 2008, en vernaamlik of die verandering in politieke regimes tydens en in die postapartheid eras tot verandering bygedra het in die woud se vorm. Om hierdie doelwitte te breik is die volgende analises gedoen: - Kwalitatiewe en kwantitatiewe ruimtelike analises van woudverandering; - Analises van die korrelasie tussen hierdie fisiese omgewingsverandering en politieke verandering in die land; - Analise van die persepsie van mense wat in die Dukuduku woudgebied woon. Die Dukuduku gronddekking is gekarteer met behulp van lugfotos, waarvoor ArcGIS 9.3 gebruik is om te bepaal of daar noemenswaardige verandering in die gebied plaasgevind het van 1960 tot 2008, in reaksie op hulpbrongebruike, en om ‘n volhoubare bestuursplan gestel voor wat op die bevindinge gebaseer is. Vyf lugfotos is gebruik om verandering in gronddekking te bepaal vir die jare: 1960, 1970, 1992, 2005 en 2008. Die Gronddekking tipes is geklassifiseer in vier klasse naamlik Inheemse Woude, Plantasiebosse, Waterliggame en Ander (oop gebiede, landerye en al die mens-versteurde en getransfomeerde gebiede). Die persentasie van elke dekkingsklas is oor die jare vergelyk om die verandering in algehele grond-dekking te bepaal, en die tempo van verandering is ook bepaal, asook die tempo van verandering. Die resultate van die studie wys dat: - Die natuurlike woud toegeneem het met 11% (700 ha), teen ‘n tempo van 20.56 hektaar per jaar tussen 1960 en 1992, tgedurende die apartheidsera. Tussen 1992 en 2008, die demokratiese era, het die woude verminder met 34.4% (2472.31 ha), teen ‘n tempo van 168 hektaar per jaar. - Die gemeenskap wat in die Dukuduku woud woon verkry hulpbronne van die woud (hout en gras vir konstruksie, kuns, brandhout, medisinale plante, weiding vir vee, en voedsel). Die mense is gewillig om by te dra tot beskerming van die woud indien die owerhede hulle sou betrek in besluite wat geneem word, veral omdat die nasionale Wet op Bosse voorsiening maak vir Deelnemende Bosbestuur, wat tans nie by Dukuduku gebeur nie.

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Anning, Alexander K. "Prescribed Fire and Thinning Effects on Tree Growth and Carbon Sequestration in Mixed-Oak Forests, Ohio, U.S.A." Ohio University / OhioLINK, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1384948011.

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Maphiri, Stella. "Forest biomass energy use and perceptions on tree planting and community woodlots in households of two rural communities in Keiskammahoek, Eastern Cape, South Africa." Thesis, Stellenbosch : University of Stellenbosch, 2009. http://hdl.handle.net/10019.1/1503.

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Thesis (MScFor (Forest and Wood Science))--University of Stellenbosch, 2009.
ENGLISH ABSTRACT: Access to secure energy supplies is widely acknowledged as a critical foundation for sustainable development. Rural households are highly dependent on forest resources for their livelihoods including energy needs. Fuelwood is a non-timber forest product (NTFP) that accounts for one of the main uses of forests and woodlands. Despite substantial household electrification programmes in South Africa, the use of fuelwood as a source of energy continues. This study aimed to analyze fuelwood use patterns of two rural villages situated in Keiskammahoek in the Eastern Cape Province of South Africa in order to understand the perceptions of the community members regarding communal tree planting. The study was conducted in two rural villages, namely, Cata and Tshoxa. A total of 120 respondents from both villages were interviewed using semi-structured questionnaires to collect data on the use of fuelwood and evaluate their perception on tree planting. The study revealed that up to 77% of the people living in Keiskammahoek used fuelwood as a major source of energy and that women were the main collectors and users of fuelwood. In the rural Cata, food is cooked in three-legged pots over open fires while in Tshoxa food is mainly cooked over paraffin and electric stoves. The respondents from both villages did not have energy conservation measures in place and improved wood stoves have not been introduced in this region. The local community of Cata was also involved in tree planting on a community level, while both villages were also involved in tree planting at a household level. The study concluded that fuelwood was the most important product from the forests in both rural areas and natural forests were a valuable source of other NTFPs; most notably indigenous fruit products. In addition most of the fuelwood was used for cooking and heating purposes but that there was no deliberate use of energy efficient methods. On tree planting, the study showed that communities from both rural villages have an interest in planting trees around their households; with preference for fruit and shade trees.
AFRIKAANSE OPSOMMING: Toegang tot betroubare energieverskaffing word algemeen erken as 'n uiters belangrike grondslag vir volhoubare ontwikkeling. Plattelandse huishoudings is hoogs afhanklik van bosbronne vir hul bestaan, met inbegrip van energiebehoeftes. Brandhout is 'n nie-hout bosproduk (NHBP) wat beskou word as een van die hoofgebruike van woude en boslande. Nieteenstaande wesenlike elektrifiseringsprogramme vir huishoudings in Suid-Afrika, duur die gebruik van brandhout as 'n bron van energie voort. Hierdie studie het beoog om die gebruikspatrone van brandhout van twee plattelandse dorpe in Keiskammahoek in die Oos-Kaapse Provinsie van Suid-Afrika te ontleed en om die begrip van die gemeenskap aangaande die gemeenskaplike plant van bome te verstaan. Die studie is in twee plattelandse dorpe, naamlik Cata en Tshoxa, uitgevoer. Onderhoude is gevoer met 'n totaal van 120 respondente van beide dorpe deur die gebruik van halfgestruktureerde vraelyste om gegewens oor die gebruik van brandhout in te samel en die respondente se begrip van die plant van bome te evalueer. Die studie het aan die lig gebring dat tot 77% van die mense wat in Keiskammahoek woon, brandhout as 'n hoofbron van energie gebruik en dat vrouens die hoofgaarders en gebruikers van brandhout is. In die landelike Cata word kos in driepootpotte op oop vure gekook terwyl kos in Tshoxa hoofsaaklik op paraffien- en elektriese stowe gekook word. Die respondente van beide dorpe het nie energiebesparingsmaatreëls in plek gehad nie en verbeterde houtstowe is nog nie in hierdie streek ingebring nie. Die plaaslike gemeenskap van Cata was ook betrokke by die plant van bome op 'n gemeenskapsvlak, terwyl beide dorpe ook betrokke was by die plant van bome op 'n huishoudelike vlak. Die studie het tot ’n gevolgtrekking gekom dat brandhout die belangrikste produk van die woude in beide plattelandse gebiede is en dat die natuurlike woude 'n belangrike bron van ander NHBP’s is; veral inheemse vrugteprodukte. Daarbenewens is meeste van die brandhout gebruik vir kook- en verhittingsdoeleindes, maar daar was geen doelbewuste gebruik van energiedoeltreffende metodes nie. Op die gebied van die plant van bome het die studie getoon dat die gemeenskappe van beide plattelandse dorpe belange het in die plant van bome rondom hulle huishoudings; met voorkeur aan vrugte- en skadubome.

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Chan, Wing-ho Michael, and 陳永浩. "Characteristics and genesis of soils in Hong Kong's Fung Shui woodlands." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2000. http://hub.hku.hk/bib/B29758166.

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Schutz, Christopher John. "Site relationships for Pinus patula in the Eastern Transvaal escarpment area." Thesis, University of Oxford, 1990. http://hdl.handle.net/10413/9535.

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The largest area of commercial timber plantations in southern Africa is situated along the Eastern Transvaal Drakensberg Escarpment north of Nelspruit. The site requirements of tree species in this area are poorly understood. The purpose of this study was to examine site-tree relationships in the region and the implications of such relationships for the science of forestry. Pinus patula Schiede & Deppe in Schlecht. & Cham. was selected for the study as it is the most widely planted species in the region. In Chapter 1 the geology, geomorphology, climate, soils and vegetation of the study area are described. A geological map was compiled. Soil descriptions were based on 439 soil pits distributed so as to cover the range of site conditions in the area. The regression techniques used to identify key environmental factors and to model their relationships with tree parameters are described in Chapter 2, in which site-growth relationships specifically are investigated. In mature stands of P. patula 159 plots were established in such a way as to cover the widest variation in both site conditions and tree growth. The relationship between site index (mean top height at 20 years) and 100 site plus 10 stand parameters recorded at each plot was modelled by means of best-subsets, multiple and ridge regression. Several candidate models were compared on the basis of coefficient of determination and validation using independent data. The best model predicted the site index of the validation plots within 60 cm of the measured site index. The possible roles of the site variables identified by the models are discussed. In Chapter 3 site-foliar nutrient relationships are described. A close relationship was found between foliar and soil nutrient levels for the six major geological substrates. Site index was more accurately predicted from concentrations of individual foliar nutrients than from ratios of these nutrients. The Diagnosis and Recommendation Integrated System (DRIS), however, appeared to have greater potential for nutrient diagnosis. Provisional ORIS norms for P. patula were computed. In Chapter 4 the excessive accumulation of litter in P. patula stands was examined. Undecomposed litter layers were greater than 15 cm in thickness on nearly 25% of the 159 sites studied. Average litter layers contained greater amounts of nutrients than the underlying topsoil. Due to the colonization of the litter by tree roots, the degree of immobilization of nutrients in litter is not known. Environmental factors associated with variation in litter thickness were identified by models which explained up to 73% of the total variation. These factors are considered to act indirectly by promoting or retarding decay organisms. The possible implications of litter accumulation for the maintenance of site productivity are discussed. In Chapter 5 relationships between site and some wood properties are described. Although between-tree variation was larger than between-site variation, some important relationships with site were identified. 10% of all trees on the 159 plots had severe stem bumps. Most of the variables in a model to predict the severity of bumps could be interpreted as being associated with stem stability or exposure. The conclusion was that wind is probably the major cause of this defect. The findings of the study are summarized in Chapter 6. Particular attention is given to a synthesis of the possible roles of site factors in their relationships with the tree parameters investigated. There were strong relationships between tree parameters and mainly rainfall, altitude, soil wetness, exchangeable bases, effective rooting depth, slope position and geology. The single most deficient nutrient element appeared to be calcium. The implications for both research and management are outlined.
Thesis (Ph.D.)-University of Natal, Pietermaritzburg, 1990.

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Busse, Nielsen Anders. "Understanding and communicating forest stand structures : lifting barriers for nature-based forest management." Hørsholm : Forest & Landscape, 2006. http://www.sl.kvl.dk/upload/flr36.pdf.

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Dohou, Hontongnon Expédit Léon. "L'évolution du droit de l'environnement au regard du concept de développement durable dans les pays de l'Afrique de l'Ouest francophone." Thesis, Lyon 3, 2015. http://www.theses.fr/2015LYO30011.

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Le concept de développement durable fut promu à la Conférence de Rio de 1992avec l’adoption d’un certain nombre d’instruments juridiques. Le droit africain s’estprobablement adapté aux règles et aux principes inhérents au concept avec, commeconséquence, la refonte ou la révision des codes ou lois de protection del’environnement. Face aux problèmes environnementaux récurrents, à la difficilegestion intégrée des ressources en eau, à l’opérationnalisation critique de la solidaritéà l’eau potable pour tous, à la gouvernance environnementale défaillante, la questionde l’évolution efficiente du droit de l’environnement africain au regard du conceptde développement durable se pose. Il se révèle un insuccès de la saisie du conceptpar le droit africain. Au final, un nouveau modèle de droit de l’environnement, auprofit des pays de l’Afrique de l’Ouest, s’avère nécessaire
The concept of sustainable development was promoted in the Rio Conference in1992 with the adoption of a number of legal instruments. African law has probablyadapted to the rules and principles inherent to the concept with, as a consequence,consolidation or revision of codes and laws to protect the environment. Facingrecurrent environmental problems, the difficult Integrated water resources, criticaloperationalization of solidarity drinking water for all, the failed environmentalgovernance, the question of the efficient development of the law of the Africanenvironment in relation to the concept of sustainable development arises. It proves afailure in the seizure of the concept by the African law. Finally, a new model ofenvironmental law in favor of the countries of West Africa is necessary

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James, Barry Mark. "Vegetation succession and soil properties following the removal of pine plantations on the eastern shores of Lake St Lucia, South Africa." Thesis, 1998. http://hdl.handle.net/10413/10302.

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Pine plantations have been established on secondary grassland on the dune systems of the Eastern Shores of Lake St Lucia, KwaZulu-Natal, South Africa for the past 40 years. These plantations have been progressively felled for the past six years, and will continue to be felled until the year 2011, by which time they will be eliminated. Space-for-time substitution was used to determine the direction of both woody and herbaceous vegetation succession and to predict possible future management implications for the Eastern Shores. Soil samples were taken from undisturbed grassland, grassland with trees, dune forest, pine plantations, and clearfelled areas at various successional stages. To determine the effects of the pine plantations on the soils of the area, soils were subjected to particle size analysis, and determination of pH, organic carbon, phosphorus, exchangeable bases, iron and aluminium. Minimal modification of the sandy soils by the pine plantations was found to have occurred. That which did occur was shown to be short-term, and to be ameliorated by the establishment of an indigenous woody understorey, resembling pioneer dune forest. Soil under plantations was shown to have a lower pH and cation exchange capacity than under opposite indigenous vegetation but no other direct effects were observed. The direction of succession was determined by the nature of the indigenous vegetation adjacent to the plantation. Pine plantations were shown to facilitate succession towards dune forest by the exclusion of fire, provision of perches and refugia for forest-dwelling animals, and creation of a forest environment for the establishment of trees. However, the extent of re-establishment of indigenous dune forest under pine plantations was shown to be directly related to the nature of the adjacent indigenous vegetation, be it grassland, grassland with trees or dune forest.
Thesis (M.Sc.)-University of Natal, Pietermaritzburg, 1998.

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Isaac, Marney Elizabeth. "Ecological and social interactions in sustainable agroforestry management: Cocoa in Ghana /." 2008. http://proquest.umi.com/pqdlink?did=1647790691&sid=5&Fmt=2&clientId=12520&RQT=309&VName=PQD.

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McClellan, Michael H. "Soil carbon and nutrient dynamics of windthrow chronosequences in spruce-hemlock forests of southern Alaska /." 1990. http://hdl.handle.net/1957/13377.

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Wang, Sen. "Multitemporal classification of vegetation in the Oregon Coastal Range using landsat multispectral scanner data /." 1988. http://hdl.handle.net/1957/10421.

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Horswell, Michael Wilbur. "Spatial modelling to establish priorities for erosion control in commercial forestry plantations." 2002. http://hdl.handle.net/10413/4514.

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Commercial forestry is recognized for both its economic contribution as well as its environmental impact. Of particular concern, is the soil erosion and sedimentation of watercourses associated with forestry plantations. Environmental laws regulate many of the activities of the forestry sector. It is critical that the forestry sector ensure that its operations are compliant with the legal requirements that govern its use of natural resources. In pursuing legal compliance it is necessary to ensure that erosion control strategies are developed so as to ensure the positive effects of any interventions are optimised. The identification of areas that are particularly at risk to erosion or contribute to sediment delivery is an essential component in prioritising areas for management interventions. Establishing the erosion potential for commercial forestry areas is readily accomplished through the application of existing models. Process based erosion models generally have greater data requirements than the empirically derived USLE-based models. Given the paucity of data available, the latter approach was adopted. Two methods of topographic sub-factor derivation were investigated, those associated with the RUSLE (Renard, Foster, Weesies & McCool1991) and the Unit Stream Power method presented by Moore and Burch (1986). Since no existing methods identifying delivery risk areas existed, a method was developed based on principles and factors identified in the literature. Additionally, methods for identifying topographic assets, in terms of sediment attenuation, were developed. From these models three indices were derived; sediment supply, delivery risk and sediment attenuation. Thereafter, the mean Sediment Supply Index was divided by stream length for small catchments defined within the landscape to derive an index of sediment loading to streams. This index is used to identify priorities for management intervention across the landscape. The mean slope and sediment supply is used to develop buffer width recommendations for the streams draining the catchments, using a method developed by Karssies and Prosser (2001). Using the three indices in conjunction it is possible to make on-site and off-site erosion control recommendations as well as identify and exploit any natural features that can be utilized in erosion control.
Thesis (M.Sc.)-University of Natal, Pietermaritzburg, 2002

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Govender, Pramanathan. "Soil invertebrate pests in the re-establishment of plantations in South Africa." Thesis, 2003. http://hdl.handle.net/2263/26064.

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Please read the abstract provided for each separate chapter and the General Summary (Chapter 9) added to the section 00front
Thesis (PhD (Entomology))--University of Pretoria, 2005.
Zoology and Entomology
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42

Wilkinson, Melanie. "Soil and water criteria and indicators for the sustainable management of industrial plantations." Thesis, 1999. http://hdl.handle.net/10413/5409.

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43

Savitri, Endang. "The use of GIS and remote sensing to identify areas at risk from erosion in Indonesian forests : a case study in central Java : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Natural Resource Management at Massey University, Palmerston North, New Zealand." 2006. http://hdl.handle.net/10179/1506.

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Environmental degradation and soil erosion begins when production forests are harvested. Unfortunately, logging cannot be avoided in plantation forests and since this operation can render the land more susceptible to erosion, any negative impacts need to be addressed properly. Erosion potential is predicted by evaluating the response of land cover, soil and slope to the impact of rainfall and human activities. The role of remote sensing and geographical information systems (GIS) in erosion prediction is to collect information from images and maps; combine and analyse these data so that it is possible to predict the erosion risk. The objective of this study was to produce a method to identify areas most susceptible to erosion and predict erosion risk. It is intended that the method be used particularly by forestry planners and decision makers so that they can improve forest management, especially during logging. The study area was within Kebumen and Banjarnegara districts of Central Java, Indonesia. Imagery used included a Landsat 7 satellite image (28th April 2001) and panchromatic aerial photos (5th July 1993). Other data was derived from topographical, soil, and geological maps, and 10 years of daily rainfall data from 17 rainfall stations. Predicting erosion in this study was done by combining rainfall, slope, geology, and land cover data. The erosion risk was predicted using land cover and soil type and depth. A rainfall map was generated using a thin plate spline method. A slope map was derived from a DEM which was generated by digitizing contours and spot heights from topographic maps. A geological map was derived from Landsat image classification with assistance from a 1:100000 scale geological map; and a land cover map was produced from an interpretation of the Landsat image and aerial photographs. A stratified classification technique was used to delineate land covers in the study area with an accuracy of 44%. The low accuracy could be attributed to the complexity of the area and the temporal variation in the data acquisition. The analysis of erosion risk showed that mixed forests and monotype forest experienced high and moderately high erosion risk. This condition supported the contention that harvest plans must incorporate soil conservation measures.

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Dissertations / Theses on the topic 'Forests and forestry Soil surveys'

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