Academic literature on the topic 'Agroforestry Models'

The successful adaptation of cocoa clones from Sulawesi in Lampung Province, especially since the release of the MCC clone in 2015, has increased farmers' interest in rehabilitating cocoa plantations, carrying out cloning and replanting using these superior clones. This study aims to study the structure of young cocoa agroforestry vegetation and farmer income in Air Naningan District, Tanggamus Regency.The research was conducted using a survey method. The sample agroforestry gardens selected purposively as models were young agroforests with complex vegetation structures and agroforests with simple vegetation structures. The results of this study indicate that the rehabilitated young cocoa-based agroforestry vegetation structure is affected by the previous tree stands. In addition, the vegetation is dominated by banana plants as productive shade so that the main crops are cocoa and bananas. In complex agroforestry systems, more types of associated crops are found than in simple agroforestry systems. Important structures as characteristics of young cocoa agroforestry are young interplanting which will later become the main crops, namely cocoa, coffee and avocado. In addition, in complex agroforestry types, tree structures with stump sprouts (regrowth trees) are found which are often pruned as goat fodder. In both types of agroforestry, various types of understorey crops were found from the food crop group, vegetables, fruit, and spices. Weekly revenue for rehabilitated cocoa-based agroforestry come from cocoa and banana yields. Palm sugar (Arenga pinnata) production is an important source of daily revenue for agroforestry farmers who manage palm trees. Key words : Agroforestry, Arenga, banana, cacao, coffee, rubber, rehabilitation, revenue, taro

This study analyses the contribution of agroforestry to the achievement of SDGs based on the performance of agroforestry and North Korea's Voluntary National Review (VNR). Since the early 2000s, North Korea has promoted agroforestry and worked with the Swiss Agency for Development Cooperation (SDC), the World Agroforestry Centre (ICRAF), and the FAO to expand agroforestry projects. Agroforestry has contributed to the achievement of food security and land restoration in SDG2 and SDG15. The achievement of SDGs from individual agroforestry pilot projects since the early 2000s allows the assessment of agroforestry's contribution to SDGs. North Korea is likely to restore degraded forests by sustainable forest management (SDG15), which emphasises the need for new land cultivation in the VNR to strengthen food security (SDG2). Because agroforestry practices can simultaneously enhance food, nutrition, environmental, and energy security, agroforestry can further contribute to the achievement of other SDGs by discovering models that reflect local characteristics and inducing residents to participate through a strict evaluation of their effectiveness and the use of 'sloping land' management accompanied by the development of cultivation technologies suitable for mixed management with various trees and crops.

Climate change, increasing environmental pollution, continuous loss of biodiversity, and a growing human population with increasing food demand, threaten the functioning of agro-ecosystems and their contribution to people and society. Agroforestry systems promise a number of benefits to enhance nature’s contributions to people. There are a wide range of agroforestry systems implemented representing different levels of establishment across the globe. This range and the long time periods for the establishment of these systems make empirical assessments of impacts on ecosystem functions difficult. In this study we investigate how simulation models can help to assess and predict the role of agroforestry in nature’s contributions. The review of existing models to simulate agroforestry systems reveals that most models predict mainly biomass production and yield. Regulating ecosystem services are mostly considered as a means for the assessment of yield only. Generic agroecosystem models with agroforestry extensions provide a broader scope, but the interaction between trees and crops is often addressed in a simplistic way. The application of existing models for agroforestry systems is particularly hindered by issues related to code structure, licences or availability. Therefore, we call for a community effort to connect existing agroforestry models with ecosystem effect models towards an open-source, multi-effect agroforestry modelling framework.

Chhattisgarh state has very diverse forest ecosystem and long history of traditional agroforestry. An agroforestry practice is location specific and depends on nature of agro-climatic zone. In Chhattisgarh, farmers are doing this farming practices based on fulfilling their diverse need and improvement of socioeconomic condition but stilldata is insufficient to explore more agroforestry practices in the state. In this context, assessment of different agroforestry models gives not only sufficient data but also open a door for conservation of biological diversity.. Different models like’s Boundary plantations, Agri-silviculture system, Horti-silvicuture, Silvi-pasture, Kitchen garden and Block plantation are used by farmers in Dhamtari. All models are dependent on location characteristic, land use type, soil type, climate and market requirement. This paper highlights the different models of Agroforestry, specific model for the specific sites, lacuna in models faced by farmers and role of agroforestry models in socioeconomic upliftment.

Cocoa-based agroforests play an important role in farmer livelihood and the global environment; however, despite these facts, their low yields and tree aging put at risk their fate. This project investigated the carbon storage potential, productivity, and economics of different agroforestry arrangements of cocoa (Theobroma cacao) with Melina (Gmelina arborea) trees, in the southwest of Colombia. We established the experiment under a Randomized Complete Blocks design with seven treatments and three repetitions. Different allometric models were tested. Allometric models were made for G. arborea trees with dbh, ranging between 30.24 and 50.11 cm. The total carbon accumulation fluctuated between 49.2 (Treatment 4) and 88.5 t ha−1 (Treatment 2), soil organic matter (SOM) ranged between 9 and 17%, bulk density decreased from 0.83 to 0.77 g cm−3. Cocoa yield ranged between 311 kg ha−1 year−1 (Treatment 7, traditional farm) and 922 kg ha−1 year−1 (Treatment 6). Treatment 6 showed the best performance with a net present value (NPV) of COP 1,446,467 (US $337.6), an internal rate of return (IRR) of 42%, and a cost-benefit ratio (B/C) of 1.67%. The benefits of AFS were also evidenced in some of the physical and chemical soil properties. Despite local marginality, these cocoa agroforest arrangements are a viable alternative to improve the traditional (local) cocoa systems because cacao agroforest arrangements increased cacao yield and carbon storage becoming a suitable alternative to improve traditional systems.

Abstract The forest land has great potential to provide food and also contributes to achieving Indonesia’s forest and other land uses (FOLU) Net Sink 2030, as a concrete contribution of the forestry sector to addressing national and global needs, which can be done by promoting smart agroforestry. This research aims to provide smart agroforestry model of sengon (Falcataria moluccana) with arrowroot and cardamom, to analyze the sengon growth, the arrowroot and cardamom biomass productivities under the agroforestry models. The split-plot design was employed with six cropping pattern as the main plot, in three agroforestry models (sengon-arrowroot; sengon-cardamom; sengon-arrowroot-cardamom) and three monoculture plots, and three levels of the dosage of manure as subplots (0; 250; 500 g). The results showed that higher growth of sengon was found in the three agroforestry models (3.0-3.5 m3.ha−1) compared to monoculture (2.1 m3.ha−1). The highest dry weight of leaf, stem, root, tuber, fruit bunch and total biomass of arrowroot and cardamom was produced in the monoculture. These agroforestry models have the potential to support food security and Indonesia’s FOLU Net Sink 2030, which will be prospective mainstreaming in implementing Social Forestry programs.

Agroforestry practices play an inevitable role in reinforcing the livelihood of millions of small-scale farmers while ensuring sustainable food security throughout the world. The significance of practicing various strategies of agroforestry models in densely populated countries like Bangladesh is highly recognized according to livelihood functionalities. To achieve the sustainable goals of the United Nations, identifying potential agroforestry practices along with their impacts towards socio-economic, and ecological demands is crucial. Socio-economic interactions are highly influenced by livelihood improvement and assurance of food security for the participants. Madhupur Sal forest is one of the major sources of diversified combination agroforestry systems practiced by the people around it. Age, education, annual income, and agroforestry knowledge had a significant relationship with the farmers' opinions on socio-economic development through agroforestry practices. Sustainable livelihood capitals (Human, Social, Physical, Financial, and Natural) were improved in each model we determined, and agroforestry multi-functionally increased food security ensuring 94% yearly food sufficiency, and 6% sufficiency for two-thirds of the year according to the response variables. This study depicted various prospects for livelihood enhancement and food security concerning diverse agroforestry models.

Domestication of forest resources and artificialization of forest ecosystems in tropical forest areas are often encompassed in a linear way: from wild resources to genetically improved trees, from complex ecosystems to controlled tree plantations. This linear evolution might be true for professional forestry or horticulture. However, it does not embrace the complexity of smallholder farmers practices for forest resources utilization. Incorporating forest resources in production systems is not a new practice in the tropics, it even constitute the very basis of a whole facet of indigenous agricultures. But this agroforestry practice is not usually considered as a full domestication process. And, in spite of an increasing amount of academic interest for indigenous forest-like plantation models, agroforestry research is not yet fully considering the prospects of these models as far as forest species are concerned. The paper focuses on the discussion of Indonesian examples of ecosystem manipulation and plant domestication. Complex agroforestry systems have been developed by local people for the management of resources ranging from locally consumed forest fruits to highly valuable industrial products such as resins and latexes. This indigenous agroforestry is presented as an elaborate process of total transfer, not only of selected forest resources, but also of true forest structures, from the sphere of 'nature' to that of 'agriculture'. This process is analysed as a particular domestication strategy which integrates conventional species domestication techniques to an original attempt of ecosystem domestication. Prospects for further developing this 'agroforest strategy' for the domestication of forest species are then discussed.

Land and forest management practices in developing countries have resulted in millions of hectares of degraded lands. This is caused by policy implementation unable to synergize between conservation-ecological goals, and the economic needs of farmer households. This study aims to showcase a model for bringing together economic and ecological interests more closely in line with one another. Furthermore, the study also presents an institutional structure of a program that could help to establish agroforestry-based land rehabilitation policies. The research employed includes a combination of Farming Income Analysis and Interpretative Structural Modeling Analysis. The results show that farming income, when employing agroforestry technology is higher than non-agroforestry approaches. Furthermore, agroforestry technology supports critical land rehabilitation and provides conditions for longer term sustainability. Therefore, a programmatic institutional approach is needed to support these dual goals. We identify that a programmatic approach would include: (1) applying conditions of an agroforestry system as a holistic structured unit, (2) improvement of farmer knowledge and skills, (3) increasing the role and capacity of relevant institutions, (4) improving coordination between sectors, (5) developing conservation agriculture systems, (6) improving bureaucratic support systems, and (7) strengthening control and supervision functions. These elements imply that implementation of agroforestry technology requires institutional support in designing policy for critical land rehabilitation, of which would have significant economic and ecological outcomes on critical lands.

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.<br>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.

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 <i>Phaseolus vulgaris</i> cv. Argus and <i>Populus trichocarpa</i> X <i>P. deltoides</i> 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.

[EN] The aim of this Thesis is to establish methodologies to improve agricultural produc-tion techniques, biodiversity conservation, and forecast of air quality, through the analytical capacity of Geographic Information Systems. Several methodologies are proposed to integrate both the geographic component of data and methods, in order to provide a practical, transferable, and integrated solution to the increasing need for environmental studies at larger scales. Initially, a plot-based approach to detect fraction of tree cover from high spatial resolution images in an Irrigation Community is proposed. The calculation of quality rates for the management of Irrigation Communities is important, and requires accurate and up-to-date knowledge of water requirements of each specific crop. The computation of the shadow fraction of vegetation cover on large areas needs of systems to able to integrate the spatial component and enable accurate results. This study presents a shadow fraction approach based on classification of high spatial resolution orthoimages acquired within the Spanish National Plan of Survey of the Territory (PNOT). The results of the classification are subsequently used in a Geographic Information System for irrigation management. Secondly, methodology for the integration of geospatial data from different sources is presented. This method aims to predict actual vegetation models, on a forested Natural Park. The quantitative spatial information is used to characterize a 25 x 25 m grid, includes: (1) topographic descriptors and the solar irradiation metrics, (2) texture features computed from aerial photography, and (3) vegetation indices informing about the vegetation status. A multivariate method is proposed by overlapping layers in a GIS. The results, are tested using independent samples, and point out to the potential of these techniques to provide and to estimate actual vegetation maps as guide in the restoration of forest ecosystems. The last study, is a forecast and evaluation of air pollution related to transport systems in urban areas. The method relies on three different geospatial data sourcess: meteorology conditions, traffic emissions, and street geometry. An inverse model calculation of dispersion of pollutants to determinate emissions of the actual car feet to provide factor emission the methodology uses. A cartographical model is defined in to integrate the geospatial data sets (i.e. measured CO concentrations, Cadastral data, and LIDAR data) with mathematical applied. The results of factor emissions have been tested in other cities. The defined model is used to estimate spatial distribution air pollutant in streets of Valencia city center and the results are represented via maps. The integration of spatial components to traditional methods allows to predict and to describe as working the phenomena in the nature. Additionally, the production of maps of phenomena improves the potential of the analysis, enable to reach more meaningful results. In order to understand and research interactions on them, these systems enable to combine different analysis disciplines and methods. For example, the atmosphere and the environment can be integrated throughout scale in space and time. This Thesis opens up various lines of research to improve our knowledge on agriculture, natural environment, and air quality. Future research may combination and fusion of methodologies to better understand the influence of vegetation cover on air quality, in order to improving the forecast of urban pollution caused by car traffic emissions.<br>[ES] Esta tesis tiene como objetivo establecer técnicas de análisis espacial para el desarrollo de métodos dirigidos a mejorar las técnicas de producción agraria, la conservación de la biodiversidad y evaluar el pronóstico de la calidad de aire, a través de la capacidad analítica de los Sistemas de Información Geográfica (SIG). Se proponen diversas metodologías para incorporar la componente geográfica a los datos y métodos, ofreciendo una solución práctica, transferible e integrada, a la creciente necesidad del estudio del medio que nos rodea, a escalas más amplias. El primer lugar, se propone una metodología basada en la clasificación de imágenes para automatizar la determinación de la cobertura arbórea de un cultivo en las parcelas de una comunidad de regantes. El cálculo de los índices de calidad en la gestión de riego requiere tener un conocimiento preciso de los consumos efectuados y de las necesidades de los cultivos en cada parcela. La determinación de la fracción promedio de suelo cubierto por la vegetación en grandes extensiones, como el caso de una comunidad de regantes, hace necesaria la utilización de sistemas que aporten un aspecto espacial, de manera que faciliten y hagan más preciso el cálculo de la misma. En el presente estudio, se propone un método para determinar la cobertura arbórea en cada parcela a través de una clasificación de imágenes cedidas por el Plan Nacional de Observación del Territorio (PNOT), que permite implementarlo de forma sencilla en un Sistema de Información Geográfica para la gestión del riego. A continuación, se expone una metodología para la obtención de un modelo de distribución de vegetación, (en un Parque Natural de gran valor paisajístico), a partir de datos de la presencia de vegetación forestal y variables ambientales obtenidas de diversas fuentes (modelos digitales de elevación y fotografía aéreas). La información cuantitativa extraída de cada variable es extraída a escala de pixel de 25x25 m y consiste en: (1) descriptores espaciales del relieve y de la radiación, obtenida de modelos digitales de elevación, (2) características texturales extraídas de imágenes aéreas, y (3) índices de vegetación que informan de sus características. Se aplica un método clásico multivariante al que se le incorpora la componente espacial a través de la superposición de capas en un SIG. Los resultados son cotejados con muestras independientes y evidencian la potencialidad del método para construir mapas de vegetación con el objetivo de servir de orientación para la restauración del ecosistema forestal. Finalmente, se presenta una metodología para el pronóstico de la contaminación del aire relacionada con el tráfico rodado en áreas urbanas. El método se basa principalmente en medidas de tres factores: (1) las condiciones meteorológicas, (2) la intensidad de tráfico vehicular, y (3) la geometría de la vía y la aplicación de dos modelos de dispersión de contaminante mediante modelización inversa, (con el objetivo de determinar las emisiones de la actual flota de vehículos). Se utilizan herramientas de información geográfica que integran, a través de un modelo cartográfico, información de diversas fuentes (medidas de concentración de CO, datos catastrales y datos LIDAR) y uso de varios modelos matemáticos. Los resultados de los factores de emisión han sido comparados con los resultados obtenidos en otros estudios desarrollados con la misma metodología, tras su validación se han aplicado los dos modelos de dispersión para estimar la distribución espacial del contaminante en algunas vías del centro de la ciudad de Valencia. La incorporación de la componente espacial a métodos tradicionales sirve de base para predecir y conocer cómo funcionan los fenómenos en la naturaleza, a la vez que permite la creación de una cartografía de los elementos utilizados para el análisis, la investigación y la divulgación<br>[CAT] Aquesta tesi té per objectiu establir tècniques d'anàlisi espacial per al desenvolupament de mètodes dirigits a millorar les tècniques de producció agrària, la conservació de la biodiversitat i per avaluar el pronòstic de la qualitat de l'aire, mitjançant la capacitat analítica dels Sistemes d'Informació Geogràfica. Es proposen diferents metodologies per tal d'incorporar la component geogràfica a les dades i mètodes, oferint una solució pràctica, transferible i integrada a la necessitat creixent de l'estudi del medi que ens envolta, a escales més amplies. Primerament, es proposa una metodologia basada en la classificació d'imatges per tal d'automatitzar la determinació de la cobertura arbòria d'un cultiu a les parcel¿les d'una comunitat de regants. El càlcul del índexs de qualitat de la gestió del reg requereix tindre un coneixement precís del consum efectuat i de les necessitats dels cultius en cada parcel¿la. La determinació de la fracció mitjana de sol cobert per la vegetació en grans extensions, com és el cas d'una comunitat de regants, fa necessària la utilització de sistemes que aporten l'aspecte espacial, de manera que faciliten i augmenten la precisió del càlcul d'aquesta fracció. Al present estudi, es proposa un mètode per determinar la cobertura arbòria a cada parcel¿la mitjançant una classificació de les imatges cedides pel Pla Nacional d'Observació del Territori (PNOT), que permet la implementació senzilla del mètode en un Sistema d'Informació Geogràfica per a la gestió del reg. Seguidament, s'exposa una metodologia per a l'obtenció d'un model de distribució de vegetació, en un Parc Natural de gran valor paisatgístic, a partir de dades sobre la pre-sència de la vegetació forestal i variables ambientals obtingudes de diferents fonts (models digitals d'elevació i fotografies aèries). La informació quantitativa extreta de cada variable és referida a escala de píxel de 25x25 m i consisteix en: (1) descriptors espacials del relleu i de la radiació, obtinguda de models digitals d'elevació, (2) característiques texturals extretes d'imatges aèries, i (3) índexs de vegetació multivariant que informen de les característiques d'aquesta. A més a més, s'utilitza un mètode clàssic multivariant al que s'incorpora la component espacial mitjançant la superposició de capes en un Sistema d'informació Geogràfica. Els resultats són comparats amb mostres independents i evidencien el potencial del mètode per construir mapes de vegetació amb l'objectiu de servir d'orientació per a la restauració de l'ecosistema forestal. Per acabar, es presenta una metodologia per al pronòstic de la contaminació de l'aire en relació al tràfic rodat en àrees urbanes. El mètode es basa principalment en les mesures de tres factors: (1) les condicions meteorològiques, (2) la intensitat del tràfic vehicular, i (3) la geometria de la via i l'aplicació de dos models de dispersió de contaminant mitjançant la modelització inversa, amb l'objectiu de determinar les emissions de la flota de vehicles actual. A més a més, s'utilitzen ferramentes d'informació geogràfica que integren, per mitjà d'un model cartogràfic, informació de diverses fonts (mesures de concentració de CO, dades cadastrals i dades LIDAR) i l'ús de diferents models matemàtics. Finalment, els resultats dels factors d'emissió es comparen amb els resultats d'altres estudis desenvolupats amb la mateixa meto-dologia. Després d'una validació, s'empren dos models de dispersió per estimar la distribució del contaminant en algunes vies del centre de la ciutat de València.<br>López Pérez, E. (2016). Modelos cartográficos en agricultura y medio ambiente: métodos de cálculo de cobertura arbórea, modelo de distribución de especies y modelo de pronostico de calidad de aire [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/62189<br>TESIS

Mestrado Mediterranean Forestry and Natural Resources Management (MEDFOR) - Instituto Superior de Agronomia - UL<br>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.<br>N/A

L'objectiu del present treball de tesi s'explica al capítol I i consisteix en la posta a punt d'un mètode de laboratori que permeti, utilitzant models a escala i mitjançant tècniques de visualització de fluids i de digitalització i tractament d'imatges, l'estudi dels mecanismes de ventilació natural en els hivernacles en condicions d'absència de vent. <br/>Al capítol II es fa una exposició dels fonaments teòrics de la ventilació natural, centrada especialment en l'estudi de l'efecte tèrmic. Es descriuen les diferents tècniques experimentals que poden ser utilitzades per al seu estudi, ja siguin a escala real o mitjançant la utilització de models a escala i en aquest darrer cas, diferenciant entre les que utilitzen aire i les que utilitzen aigua com a fluid de treball. Es fa també una breu introducció a la utilització de mètodes numèrics per l'estudi de la ventilació, així com a les tècniques experimentals més utilitzades per a la visualització de fluids. Finalment, s'indiquen les tècniques escollides per desenvolupar el mètode de laboratori objecte d'aquest treball, que consistiran en la utilització de models a escala utilitzant aigua com a fluid de treball i afegint sal per produir les diferències de densitat que serien les responsables de la ventilació per efecte tèrmic; la visualització del fluid s'aconseguirà mitjançant l'addició de colorant i les tècniques de digitalització i tractament d'imatges ens permetran quantificar les variables físiques d'interès, que seran interpretades mitjançant l'anàlisi dels criteris de semblança. <br/>L'equipament instrumental necessari tant per la simulació física del flux com per la seva visualització, obtenció d'imatges digitalitzades i processat i anàlisi d'aquestes es descriu en el capítol III i consisteix, esquemàticament, en un tanc d'aigua transparent en el que s'introdueixen les maquetes bidimensionals de l'hivernacle en posició invertida, un equip per la injecció de la solució salina i el colorant a l'interior de la maqueta, un conductímetre que permet mesurar de forma contínua la conductivitat elèctrica en un punt fix d'aquesta i enregistrar els valors obtinguts en un data-logger, una vídeo cambra amb el corresponent magnetoscopi i un ordinador personal equipat amb una targeta digitalitzadora d'imatges i amb el software adient per al processat i anàlisi de les imatges. Per als assaigs de camp s'ha construït un hivernacle a escala real, de característiques similars als utilitzats en els assaigs de laboratori, situat a l'interior d'un hivernacle de dimensions molt superiors per tal d'eliminar l'efecte eòlic; en el seu interior s'han instal·lat dos sensors de radiació neta, dues columnes de sensors per determinar la temperatura de l'aire i sensors per determinar la temperatura del sòl a diferents fondàries. <br/>El mètode experimental de laboratori es descriu amb detall en el capítol IV i consisteix en introduir la solució salina amb el colorant a través d'orificis practicats en el "sòl" del model a escala, de forma que el flux descendent provocat per la solució salina, de densitat superior a la de l'aigua del tanc, simuli el flux de flotabilitat provocat per l'escalfament de l'aire al seu contacte amb el terra, calent per l'acció de la radiació solar. S'analitzen les lleis d'escala i es defineix el paràmetre adimensional (è) que ens permet interpretar els increments de temperatura que correspondrien, a escala real, als increments relatius de densitat obtinguts en els experiments. S'indiquen també les tècniques utilitzades per l'obtenció de les imatges digitalitzades i el seu posterior processat i anàlisi i s'estudia la relació existent entre els increments d'intensitat de gris obtinguts en punts homòlegs de diferents imatges d'un mateix experiment i les concentracions de colorant dels punts esmentats; en ser menyspreable en tots els experiments l'efecte de la difussivitat tant de la sal com del colorant, podrem establir la relació existent entre els increments d'intensitat de gris observats en cada punt (píxel) de les imatges capturades i els increments de densitat corresponents. Es planteja un assaig específic per conèixer amb precisió la relació esmentada. <br/>En el mateix capítol, a fi i efecte d'obtenir, amb procediments diferents, resultats que puguin ésser contrastats amb els obtinguts amb el mètode de laboratori proposat, es planteja un model teòric que permet predir els increments de temperatura esperats en funció de les característiques geomètriques de l'hivernacle i de les condicions exteriors. Amb la mateixa finalitat, es proposen assaigs de camp destinats a fer una estimació dels fluxos de calor existents en hivernacles de característiques similars als utilitzats en els assaigs de laboratori i mesurar els increments de temperatura que en aquests es produeixen. <br/>Els resultats obtinguts en els diferents tipus d'assaigs s'agrupen en el capítol V, on en primer lloc s'indica la relació obtinguda entre la concentració de colorant i l'increment d'intensitat de gris de les imatges , que és de tipus exponencial, si bé en aquells casos en que la disminució de la intensitat de gris sigui inferior al 35% pot establir-se una relació de tipus lineal. En els assaigs de laboratori realitzats amb maquetes a diferents escales d'un mateix tipus d'hivernacle, s'obté la distribució dels valors de è en les seccions transversals dels diferents assaigs, es fa una descripció de les característiques del flux i i s'estableix el número de Reynolds a partir del qual les característiques del flux seran independents de la viscositat, que per la geometria estudiada es situa al voltant de 900. Es formula la metodologia per l'elecció de les condicions experimentals adients (escala de longituds i cabal, increment relatiu de densitat i concentració de colorant de la solució salina) que ens permetin aconseguir, d'una banda, una simulació realista de les característiques del flux i d'altra banda, que els resultats dels experiments ens surtin dins d'un rang de valors que faciliti al màxim la seva interpretació. <br/>En el mateix capítol es presenten els resultats obtinguts de l'aplicació del model teòric proposat i dels assaigs de camp realitzats, així com la comparació d'aquests amb els obtinguts en els assaigs de laboratori, no observant-se desviacions importants entre els increments de temperatura obtinguts pels diferents procediments. Finalment es presenten els resultats obtinguts en assaigs de laboratori realitzats amb altres models d'hivernacles de geometries diferents a la utilitzada com a referència per la posta a punt del mètode, indicant-se en cada cas la distribució dels valors del paràmetre adimensional è; en el cas dels hivernacles multi-túnel, tot i que per limitacions en les dimensions del dispositiu experimental no s'arriba a assolir les condicions necessàries per obtenir una simulació realista del flux, s'observa un comportament d'aquest força diferent d'aquell que seria previsible per aplicació de la teoria de l'eix neutre. <br/>El capítol VI és el dedicat a les conclusions, al mateix temps que s'indiquen alguns suggeriments de cara a la futura continuació de la recerca.<br>El objetivo del presente trabajo de tesis se explica en el capítulo I y consiste en la puesta a punto de un método de laboratorio que permita, utilizando modelos a escala y mediante técnicas de visualización de fluidos y digitalización y tratamiento de imágenes, el estudio de los mecanismos de ventilación natural en los invernaderos en condiciones de ausencia de viento. <br/>En el capítulo II se hace una exposición de los fundamentos teóricos de la ventilación natural, centrada especialmente en el estudio del efecto térmico. Se describen las diferentes técnicas experimentales que pueden ser utilizadas para su estudio, ya sean a escala real o mediante la utilización de modelos a escala y en este último caso, diferenciando entre las que utilizan aire y las que utilizan agua como fluido de trabajo. Se hace también una breve introducción a la utilización de métodos numéricos para el estudio de la ventilación, así como a las técnicas experimentales más utilizadas para la visualización de fluidos. Finalmente, se indican las técnicas elegidas para desarrollar el método de laboratorio objeto de este trabajo, que consistirán en la utilización de modelos a escala empleando agua como fluido de trabajo y añadiendo sal para producir las diferencias de densidad que serían las responsables de la ventilación por efecto térmico; la visualización del fluido se conseguirá mediante la adición de colorante y las técnicas de digitalización y tratamiento de imágenes nos permitirán cuantificar las variables físicas de interés, que serán interpretadas mediante el análisis de los criterios de semejanza. <br/>El equipo instrumental necesario tanto para la simulación física del flujo como para su visualización, obtención de imágenes digitalizadas y procesado y análisis de estas se describe en el capítulo III y consiste, esquemáticamente, en un tanque de agua transparente en el que se introducen las maquetas bidimensionales del invernadero en posición invertida, un equipo para la inyección de la solución salina y el colorante en el interior de la maqueta, un conductímetro que permite medir de forma continua la conductividad eléctrica en un punto fijo de esta y registrar los valores obtenidos en un data-logger, una vídeo cámara con el correspondiente magnetoscopio y un ordenador personal equipado con una tarjeta digitalizadora de imágenes y con el software apropiado para el procesado y análisis de las imágenes. Para los ensayos de campo se ha construido un invernadero a escala real, de características similares a los utilizados en los ensayos de laboratorio, situado en el interior de un invernadero de dimensiones muy superiores para eliminar el efecto eólico; en su interior se han instalado dos sensores de radiación neta, dos columnas de sensores para determinar la temperatura del aire y sensores para determinar la temperatura del suelo a distintas profundidades. <br/>El método experimental de laboratorio se describe con detalle en el capítulo IV y consiste en introducir la solución salina con el colorante a través de orificios practicados en el "suelo" del modelo a escala, de forma que el flujo descendente provocado por la solución salina, de densidad superior a la del agua del tanque, simule el flujo de flotabilidad provocado por el calentamiento del aire en su contacto con el suelo, caliente por la acción de la radiación solar. Se analizan las leyes de escala y se define el parámetro adimensional (è) que nos permite interpretar los incrementos de temperatura que corresponderían, a escala real, a los incrementos relativos de densidad obtenidos en los experimentos. Se indican también las técnicas utilizadas para la obtención de las imágenes digitalizadas y su posterior procesado y análisis y se estudia la relación existente entre los incrementos de intensidad de gris obtenidos en puntos homólogos de diferentes imágenes de un mismo experimento y las concentraciones de colorante en dichos puntos; al ser despreciable en todos los experimentos el efecto de la difusividad tanto de la sal como del colorante, podemos establecer la relación existente entre los incrementos de intensidad de gris observados en cada punto (pixel) de las imágenes capturadas y los incrementos de densidad correspondientes. Se plantea un ensayo específico para conocer con precisión la citada relación. <br/>En el mismo capítulo, con el fin de obtener, con procedimientos distintos, resultados que puedan ser contrastados con los obtenidos con el método de laboratorio propuesto, se plantea un modelo teórico que permite predecir los incrementos de temperatura esperados en función de las características geométricas del invernadero y de las condiciones exteriores. Con la misma finalidad, se proponen ensayos de campo destinados a hacer una estimación de los flujos de calor existentes en invernaderos de características similares a los utilizados en los ensayos de laboratorio y medir los incrementos de temperatura que en estos se producen. <br/>Los resultados obtenidos en los distintos tipos de ensayo se agrupan en el capítulo V, en el que se indica, en primer lugar, la relación obtenida entre la concentración de colorante y el incremento de intensidad de gris de las imágenes, que és de tipo exponencial, si bien en aquellos casos en que la disminución de la intensidad de gris sea inferior al 35% puede establecerse una relación de tipo lineal. En los ensayos de laboratorio realizados con maquetas a distintas escalas de un mismo tipo de invernadero, se obtiene la distribución de los valores de è en las secciones transversales de los distintos ensayos, se describen las características del flujo y se establece el número de Reynolds a partir del cual las características del flujo serán independientes de la viscosidad, que para la geometría estudiada se sitúa alrededor de 900. Se formula la metodología para la elección de las condiciones experimentales adecuadas (escala de longitudes y caudal, incremento relativo de densidad y concentración de colorante de la solución salina) que nos permitan conseguir, por un lado, una simulación realista de las características del flujo y por otro lado, que los resultados de los experimentos nos salgan dentro de un rango de valores que facilite al máximo su interpretación. <br/>En el mismo capítulo se presentan los resultados obtenidos de la aplicación del modelo teórico propuesto y de los ensayos de campo realizados, así como la comparación de estos con los obtenidos en los ensayos de laboratorio, no observándose desviaciones importantes entre los incrementos de temperatura obtenidos por los distintos procedimientos. Finalmente se presentan los resultados obtenidos en ensayos de laboratorio realizados con otros modelos de invernadero de geometrías distintas a la utilizada como referencia para la puesta a punto del método, indicándose en cada caso la distribución de los valores del parámetro adimensional è; en el caso de los invernaderos multi-túnel, a pesar de que por limitaciones en las dimensiones del dispositivo experimental no se llegan a alcanzar las condiciones necesarias para obtener una simulación realista del flujo, se observa un comportamiento de este muy distinto del que seria previsible por aplicación de la teoría del eje neutro. <br/>El capítulo VI es el dedicado a las conclusiones, al mismo tiempo que se indican algunas sugerencias con vistas a la futura continuación de la investigación.<br>The aim of the present work is explained in chapter I and consists in setting up a laboratory method that permits, using scale models and through fluid visualization and digital image processing, the study of the natural ventilation mechanisms in greenhouses without a wind effect. <br/>In chapter II, the theoretical basis of natural ventilation is developed, focusing mainly on the study of the thermic effect. Different experimental techniques are described, which may be used for its study, both at full scale or using scale models, and in that last case distinguishing between those using air and those using water as a work fluid. A short introduction on the utilization of numerical methods for the study of ventilation, as well as the most frequently used experimental techniques in fluid visualization is presented. Finally, the chosen techniques to develop the laboratory method subject of the present work are indicated. They consist in the utilization of scale models employing water as a work fluid and adding salt to produce the density differences which are responsible of ventilation by thermic effect. Fluid visualization is achieved by means of dye addition. Digital image processing allows to quantify physical variables of interest. Data are analyzed using similarity criteria. <br/>Instrumental equipment needed for physical flow simulation as well as visualization, digital image processing and analysis is described in chapter III. It basically includes a clear water tank where bidimensional greenhouses scale models are sunk upside-down, a flow pump to inject salty solution and dye inside the model, a conductivity meter measuring continuously at a fixed point of the cross section with a data logger connected to it, a video camera with the corresponding magnetoscope, and a personal computer equipped with an image digitizing card and a software package to process and analyze images. For the field trials, a full scale greenhouse was built up with similar features to those used in laboratory trials, placed inside a much bigger greenhouse in order to avoid the wind effect. Two net radiation sensors were located inside the greenhouse, as well as two sensor columns to measure air temperature and sensors to determine soil temperatures at different depths. <br/>The laboratory method is described with detail in chapter IV. It consists in distributing the salt solution, with the dye, through a set of small holes made in the floor of the scale greenhouse. Thus, the descending flow produced by the saline solution, of density higher than the tank water, simulates the buoyancy flux due to the heating of the greenhouse air in contact with the soil surface, whose temperature is warmer than the surrounding air due to the action of solar radiation. Scale laws are used and a dimensionless parameter (è) is defined in order to convert relative density differences from the scale models into temperature differences in the full scale situation. Techniques used to obtain digitized images are also indicated, as well as their further processing and analysis. The existing relationship between increments of grey intensities obtained at corresponding points of different images from the same experiment, and the dye concentrations at those points are studied. Assuming that salt and dye diffusivity effect is negligible in all experiments, the relationship between grey intensity increments observed at each point (pixel) of the captured images and the corresponding density increments can be established. <br/>In the same chapter, different methods are proposed in order to obtain results that may be faced to those recorded with the trained laboratory method. A theoretical model is proposed in order to predict the expected temperature increments as a function of geometric characteristics of the greenhouse under different external conditions. With the same goal, field trials with greenhouses of similar features to those employed in the laboratory assays are proposed in order to estimate heat fluxes and to measure temperature increments produced inside them. <br/>Results obtained in different types of trials are grouped in chapter V, which points out, in the first place, the relationship obtained between dye concentration and grey intensity increment of images, which results to be exponential. However, in those cases where the reduction of grey intensity is less than 35%, a linear relationship may be established. In all field trials carried out with the same type of greenhouse models at different scales, a distribution of è values in transversal sections of each assay is obtained. Characteristics of fluxes are described. Different experiments are carried out in order to estimate the minimal Reynolds number which allows to neglect viscosity effects. For the shape of greenhouse under study, the minimum Re number to be maintained is determined to be close to 900. A methodology to select the optimal experimental conditions is formulated (length scale, and flow, relative density increment and dye concentration of the salty solution) in order to obtain, on one side, a realistic simulation of flow characteristics and, on the other side, results fallen into a range of values which enable an easy interpretation. <br/>In the same chapter, results obtained from the proposed theoretical model and the field trials developed are presented, as well as the comparison with those obtained in the laboratory. Agreement between the results obtained by the different methods is satisfactory. Finally, results obtained in laboratory assays carried out with greenhouse models of other shapes, different from the one used as a reference for adjusting the method, are presented. In each case distribution of è values are indicated. In the case of the multitunnel greenhouses, dimensions of experimental device do not permit to achieve the required conditions to obtain a realistic flow simulation; despite this fact, the observed behaviour is very different from the one expected by application of neutral level theory. <br/>Chapter VI is devoted to conclusions, as well as some suggestions for aims of future research are pointed out.

El sector porquí Espanyol ha sofert recentment profuns canvis degut bàsicament a<br/>l'augment de la competència i al procés de globalització econòmica. Ademes, els<br/>avenços tecnológicos i el grau creixent d'especialització en el sector afavoreixen el<br/>desenvolupament i l'adopció de eienes avançades per a la pressa de decisions. En<br/>aquest context, l'objectiu d'aquesta Tesi ha estat formular i implementar un model<br/>dinàmic estocàstic del comportament productiu d'un remat de truges, basat en<br/>processos de decisió Markovians i capaç d'ésser utilitzat en condicions reals. La<br/>finalitat del model és representar alternatives de maneig reproductiu i de reposició en<br/>explotacins porcines per assistir als grangers, tècnics i gerents en la pressa de<br/>decisions en granja.<br/>El model de decisió semi-Markovià i el Markovià que s'en deriva del primer han<br/>demostrat ser models útils per la representació de les estratègies productives de<br/>maneig reproductiu i de la reposició. La disponibilitat de dades de camp de granges<br/>individuals ha permès la validació del model en situacions reals. La validació ha servit<br/>també per mostrar com el model no pot ser aplicat indiscriminadament a qualsevol<br/>granja, prèviament s'ha d'assegurar l'ajust del model a les condicions concretes de<br/>cada explotació. També s'ha ficat de manifest que quan el model s'utilitza per a<br/>calcular l'estructura de la població a l'equilibri no és necessari que la matriu de<br/>transició representi el pas de temps constant, la qual cosa ha permès treballar amb<br/>transicions associades als estats biològics que són més fàcils d'estimar (embedded<br/>Markov process), ademes, proporcionen estalvis computacionals que permeten una<br/>avaluado més ràpida d'alternatives de maneig reproductiu i la implementació<br/>d'algorismes d'optimització pel problema de la reposició més eficientes.<br/>La implementació del model de decisió semi-Markovià dins d'un sistema d'ajut a la<br/>pressa de decisions (DSS: Decision Support Systems) ha mostrat l'ús potencial del<br/>model en granja. El desenvolupament del DSS ha facilitat la disponibilitat d'un model<br/>complex com el presentat a potencials usuaris menys especialitzats. El DSS permet al<br/>granger avaluar a peu de granja diferentes alternatives productives, analitzar la<br/>sensibilitat dels paràmetres que consideri crítics i optimitzar la política de reposició.<br/>Ademes, la integració del DSS en un sistema de gestió informatitzat (BDporc®2)<br/>facilita la difusió del DSS en empreses de producció porcina i també l'obtenció de<br/>noves variables com el número de serveis por monta, la detecció de zels, la detecció<br/>de la gestació, instalacions, etc, que poden ajudar a incrementar la precisió dels<br/>resultats. El disseny sofisticat del interface del DSS ha millorat la interpretació dels<br/>resultats del model que no sempre és inmediata. La incorporació de l'anàlisi de<br/>sensibilitat permet estudiar i profunditzar en els components crítics del model que<br/>sovint resulta més important que l'obtenció d'un resultat precis. Finalment, el model de<br/>remat formulat de forma flexible, és capaç d'adaptar-se a diferents propòsits amb<br/>canvis mínims, la qual cosa contribueix a una millor comprensió dels efectes de<br/>diferentes alternatives de maneig reproductiu sobre la millora de la eficiència<br/>econòmica de tot el sistema productiu.<br>El sector porcino en España ha sufrido recientemente profundos cambios debido<br/>básicamente al aumento de la competencia y al proceso de globalización económica.<br/>Además, los avances tecnológicos y el creciente grado de especialización en el sector<br/>favorecen el desarrollo y la adopción de herramientas avanzadas para la toma de<br/>decisiones. En este contexto, el objetivo de esta Tesis es presentar la formulación e<br/>¡mplementadón de un modelo dinámico estocástico del comportamiento productivo de<br/>un rebaño de cerdas, basado en procesos de decisión Markovianos y capaz de ser<br/>usado en condiciones reales. La finalidad del modelo es representar alternativas de<br/>manejo reproductivo y de reposición en explotacines porcinas para asistir a granjeros,<br/>técnicos y gerentes en la toma de decisiones en granja.<br/>El modelo de decisión semi-Markovianos y el Markoviano que deriva del primero han<br/>demostrado ser modelos útiles en la representación de las estrategias productivas de<br/>manejo reproductivo y de la reposición. La disponibilidad de datos de campo de<br/>granjas individuales ha permitido la validación del modelo en situaciones reales. La<br/>validación ha servido también para mostrar como el modelo no puede ser aplicado<br/>indiscriminadamente en cualquier granja, previamente se asegurar el ajuste del<br/>modelo a las condiciones concretas de cada explotación. También se ha puesto de<br/>manifiesto que cuando el modelo se utiliza para calcular la estructura de la población<br/>en equilibrio no es necesario que la matriz de transición represente de paso de tiempo<br/>constante, con lo cual ha sido posible trabajar con transiciones asociadas a los<br/>estados biológicas que son más fáciles estimar (embedded Markov process), además,<br/>proporcionan ahorros computacionales que permiten una evaluación más rápida de<br/>alternativas de manejo reproductivo y la implementación de algoritmos de optimización<br/>para el problema de la reposición más eficientes.<br/>La implementación del modelo de decisión semi-Markoviano dentro de un sistema de<br/>ayuda a la toma de decisiones (DSS: Decision Support Systems) ha mostrado el uso<br/>potencial del modelo en granja. El desarrollo del DSS ha facilitado la disponibilidad de<br/>un modelo complejo como el presentado a potenciales usuarios menos especializados.<br/>El DSS permite al granjero evaluar a pie de granja diferntes alternativas productivas,<br/>analizar la sensibilidad de los parámetros que considere críticos y optimiza la política<br/>de reposición. Además, la integración del DSS en un sistema de gestión informatizado<br/>(BDporc®3) facilita la difusión del DSS en empresas de producción porcina y también<br/>la obtención de nuevas variables como el número de servicios por monta, la detección<br/>de celos, la detección de la gestación, instalaciones, etc, que pueden ayudar a<br/>incrementar la precisión de los resultados. El diseño sofisticados del interface del DSS<br/>ha mejorado la interpretación de los resultados que no siempre es inmediata. El<br/>análisis de sensibilidad incorporado permite estudiar y profundizar en los componentes<br/>críticos del modelo que a menudo resulta más importante que el disponer de un<br/>resultado preciso. Finalmente, el modelo de rebaño formulado de forma flexible, es<br/>capaz de adaptarse a distintos propósitos con cambios mínimos, lo que redunda en<br/>una mejor compresión de los efectos de diferentes alternativas de manejo reproductivo<br/>a fin de mejorar la eficiencia económica de todo el sistema productivo.<br>Spanish pig sector has gone through a deep change during recent times, that is due<br/>basically to the increase in competitiveness and the globalisation process of the<br/>economics. Furthermore, technological advances and the increasing degree of<br/>specialisation have maden possible the development and adoption of advanced tools<br/>for decision support. In this context, the objective of this Thesis has been to formulate<br/>and implement a dynamic estochastic model representing the productive behaviour of<br/>a sow herd, based on Markov decision processes. The model was aimed to be used in<br/>field condicions to analyse different management alternatives on reproduction and<br/>replacement, supporting farm managers in the decision-making process.<br/>The semi-Markovià decision model and the derived Markov decision model (embedded<br/>Markov process) have demonstrated to be useful in the representation of management<br/>alternatives on reproduction and replacement. The availability of data from individual<br/>farms has allowed the validation of the model in real situations. The validation also has<br/>served to show how the model can not be applied indiscriminately on any farm.<br/>Previously, it has been required to assess the fit of the model in specific farm<br/>conditions. Also, it is shown that when the model has been used to calculate the<br/>population structure at equilibrium was not necessary a transition matrix being time<br/>step constant. Instead have been possible to consider transitions associated to<br/>biological states that are easier to estimate, more precise and provided computational<br/>time savings. Hence the model, as it was formulated, allowed a faster evaluation of<br/>management alternatives on reproduction and an efficient impleemntation of algorithms<br/>to optimise replacement policies.<br/>The implementation of the semi-Markov model into a DSS (DSS: Decision Support<br/>Systems) has shown the potential on-farm use of the model. The development of the<br/>DSS makes easier the availability of complex models to less specialised users. The<br/>DSS allows the farm manager to evaluate on-farm different management alternatives<br/>on reproduction and optimise replacement decisions. Moreover, the integration of the<br/>DSS in a management information system (BDporc®1) makes easier the spreading of it<br/>over swine enterprises, as well the obtention of new variables like the number of<br/>services by mating, heat detections, pregnancy detection, facilities, etc, can help to<br/>increment model precision. The sophisticated dessign of the DSS interface has<br/>improved the interpretation of the model results, that not always is right direct. The<br/>addition of sensitivity análisis capability provided insight about the impact of changes in<br/>critical components of the model, that quite often result in a more interest than a single<br/>precise result. Finally, the sow herd model formulated in a flexible way, was able to be<br/>adapted to différents goals with minimum changes, thus it contribute to improve the<br/>knowledge about the effect of different management alternatives on overall economic<br/>efficiency of the system.

Made available in DSpace on 2016-06-02T18:57:18Z (GMT). No. of bitstreams: 1 2288.pdf: 709049 bytes, checksum: 694c734061c4ecba37345118443eaac2 (MD5) Previous issue date: 2008-12-17<br>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.<br>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.

AbstractCurrent research suggests that cocoa agroforestry systems could offer stable yields, additional benefits and income from shade trees, despite potential added costs, such as from the purchase of insecticides. There is a paucity of profitability studies of different cocoa agroforestry systems. Only few of them go beyond a narrow focus on cocoa yields to model the entire agroforestry system and thus do not advance our understanding of the socio-economic value of other ecosystem goods. Based on survey data covering a thousand cocoa plots and group interviews with cocoa farmers, we explore the costs and benefits at the household level of including trees in cocoa systems. Comparing low and medium tree diversity systems, we find that income from cocoa beans, timber and fruit trees are higher and labour costs are lower in plots with medium diversity, while insecticide costs are lower on low-diversity plots. Overall, net benefits were higher on cocoa plots with higher tree diversity. Thus, cocoa agroforestry systems offer cost-reduction and income-improving advantages. Since cocoa systems vary among different agro-ecological zones in Ghana, we recommend that interventions aimed at increasing tree diversity consider the specific management practices of each farming household and the location in question.

AbstractBasic information on ecosystem-based approaches to climate mitigation is provided, and their inclusion in international climate and nature conservation treaties is discussed. Key concepts around net-zero emissions and carbon removal are examined, as are the roles they play in the One Earth Climate Model, which develops a 1.5 °C-compatible scenario by combining ecosystem restoration with deep decarbonization pathways. The carbon removal potentials of the five ecosystem restoration pathways—forests and agricultural lands, forest restoration, reforestation, reduced harvest, agroforestry, and silvopasture—are provided. Land-use management options, including the creation of ‘carbon conservation zones’ (CCZ), are discussed.

Spatially extended Short Food Supply Chains (SFSCs) can enable small-scale producers' resilience capacity to external shocks, offering secure and traceable food sources. Furthermore, expanding sustainable commercial cocoa crops in spatially extended SFSCs may increase the production of cocoa beans in a way that is environmentally sustainable and socially responsible. This can involve promoting the use of agroforestry systems, which integrate trees and crops to enhance biodiversity and soil health, reducing the use of harmful chemicals. By implementing this type of SFSCs, small-scale farmers can obtain a reliable source of income while simultaneously preserving the environment. This study examines Ecuador, a major fine cocoa exporter, and aims to advance knowledge on the resources and attributes of SFSC intra-firm resilience that determine small-scale cocoa farmers' resilience capacity. Qualitative research methods reveal that small-scale farmers in spatially extended SFSCs exhibit resilience during crises, highlighting the importance of this organizational model in enduring market disruptions.

The aim of this study was to assess the ability of several distinct forestry systems in Bangladesh's northern region to sequester carbon. Three different agro-ecological zones (AEZs) were covered by the experiments: AEZ 1 (Old Himalayan piedmont plain), AEZ 3 (Tista meander flood plain), and AEZ 25 (Level barind tract). Experimental plots with three replications were randomly selected from each AEZ using a randomized complete block design (RCBD). Factor A, which represented five forestry models (Shal forest, social forest, eucalyptus cropland-based agroforestry, and mango and litchi orchard-based agroforestry systems), and Factor B, which represented the three aforementioned AEZs. To determine the total biomass accumulation, undergrowth vegetation (including herbs, shrubs, and crops) and tree growth parameters, like height and diameter at breast height (DBH), were studied. In terms of parameters like tree height, DBH, tree density, understory vegetation, and carbon sequestration in both trees and soil, the results showed significant differences across forestry systems. Notably, the Litchi orchard-based agroforestry system sequestered the least carbon, at 67.82 t/ha, whereas the Shal forest system did so at a rate of 2310.04 t/ha. Regarding the AEZs, AEZ 25 had the highest potential for sequestering carbon, measuring 644.98 t/ha, while AEZ 1 had the lowest potential, measuring 503.21 t/ha. Variability in carbon sequestration was also revealed by the interaction between AEZs and forestry systems. The Shal forest system and AEZ 3 were found to have the highest capacity at 2661.09 t/ha, while AEZ 1 and the Litchi orchards-based agroforestry system had the lowest capacity at 66.09 t/ha. In conclusion, the Shal forestry system demonstrated the highest capacity for conserving carbon and is, therefore, a promising strategy for reducing atmospheric carbon in the area. AEZ 25 demonstrated the best capacity for carbon sequestration of all the AEZs examined. Additionally, at $115,502/ha, the Shal forestry system provided the highest economic return on carbon sequestration. These findings suggest that the Shal forestry system should be given importance in Bangladesh's northern region for ecological reasons. Additionally, to balance carbon sequestration capacities between the zones, strategic tree planting programs should be implemented in AEZs 1 and 3.

The globe is now mostly concerned about climate change and its impacts on lives. The highly dense population and geographical location make Bangladesh most vulnerable to climate change. Concerning the issue, it’s a big challenge making the agriculture sector adapt as well as sequestering more carbon from the atmosphere to mitigate climate change. To address climate change impacts, the study aimed to assess carbon sequestration potentials in different fruit production models developed by the Department of AFE, Bangabandhu Sheikh Mujibur Rahman Agricultural University. The study was arranged in a single-factor randomized complete block design. The treatments were open field (T₁), aonla (Phyllanthus emblica) (T2), carambola (Averrhoa carambola) (T3), lemon (Citrus limon) (T4), aonla + carambola (T5), aonla + lemon (T6), and aonla + carambola + lemon (T7). The vegetation data, soil data, and canopy data were collected to determine carbon sequestration and its response to the drivers. The study revealed that treatment T7 had the highest biomass sequestration rates both above and below ground, as well as the total carbon content (64 tons/ha) which was followed by T5 and T6 treatments compared to T2, T3, and T4 single strata treatments. The findings revealed that the total amount of carbon content showed a positive significant response to photosynthetically active radiation leaf area index (R2 = 0.8591), total soil nitrogen content (R2 = 0.9351), canopy coverage (R2 = 0.9821) and litter fall (R2 = 0.9606). This study also explores the role of agroforestry in carbon sequestration using the multistoried fruit production model, contributing to sustainable climate change strategies, land use management, environmental resilience, and policy making.

La facultad de Ingeniería de la Universidad Tecnológica del Chocó en cumplimiento con la función social de formar de manera integral a sus estudiantes incluye dentro del diseño curricular de sus programas, el curso de ética profesional y cursos relacionados, sin embargo, ha venido comprendiendo la importancia de verlos no como un curso netamente, si no como un modelo de formación al entender que se entrega a la sociedad y a sus familias, personas con una responsabilidad cívica y con ellos mismos. En ese sentido, se presenta este trabajo que resulta del desarrollo de una experiencia de investigación en el aula con docentes y estudiantes de la facultad de ingeniería de la Universidad Tecnología del Chocó en el marco del curso de ética profesional. Su objetivo fue hacer un análisis sobre la aplicabilidad de principios éticos y morales por los docentes de la facultad en el programa de ingeniería agroforestal en el proceso de formación de sus estudiantes por lo cual se tuvo en cuenta la mirada de estos últimos cuando ya se encuentran al final de la carrera. El ejercicio investigativo se diseñó para ser realizado en dos tiempos: una primera etapa para evaluar el proceso de enseñanza – aprendizaje de la ética en los estudiantes y una segunda etapa para proponer estrategias didácticas y administrativas para mejorar el proceso. De lo anterior, se ha desarrollado la primera etapa con la evaluación del proceso de enseñanza - aprendizaje donde participaron de manera activa los docentes y los estudiantes, partiendo de reconocer que es un proceso continuo y recíproco. Esto permitió establecer el contexto ético de los profesores del programa, entre fortalezas y debilidades, conocer la percepción de los estudiantes acerca de cómo los profesores a través de su práctica docente forman personas éticas y con moral, además establecer algunas acciones de mejora para el establecimiento de una cultura ética en el desarrollo de los procesos cotidianos dentro y fuera de la institución.

This study demonstrates that the economic activity of the Amazon's natural forest has great potential yet to be developed when considering Non-Timber Forest Products (NTFPs) and those coming from agro-ecosystems (SAFs). Preliminary financial analyzes, in systems that are still incipient, point to a great potential for profitability of these alternative systems compared to traditional activities such as soybean and livestock farming, with the advantage of being conducted without degradation and deforestation, allowing the continuation with the support of the Amazonian ecological system. More research is needed to scale successful cases and more “dialogue” between the models of modern agriculture and the traditional knowledge to reach an integrated natural forest management system.

Faced with environmental degradation and strong land pressure, farmers in south-central Niger have intensified their agricultural production systems. Since the 1980s, farmers in the regions of Zinder, Maradi and Tahoua have increased the number of trees and shrubs on their fields, creating new agroforestry parklands over about 5 million hectares. This regreening is not based on tree planting, however, but on farmers protecting and managing natural regeneration of woody species on their crop lands. This has been well documented over the years, but until now, there has not been a thorough review of all of the published peer-referenced as well as grey literature. This report presents the first comprehensive state of knowledge of farmer managed natural regeneration (FMNR) in Niger. Studies show the scale and dynamics of FMNR as well as its multiple impacts. It has increased crop yields (+31 kg/ha to +350 kg/ha), and that supports family food security even in drought years. FMNR has increased the income of all social categories, even the most vulnerable women, men and youth, through the sale of fuelwood and service wood. The pruning of trees in fields has also reduced the distances travelled by women to collect fuelwood. FMNR increased the availability of fodder from trees to farmers and agropastoralists, with households practising FMNR harvesting 30-45 kg of fodder per day. Economists have not calculated all the multiple impacts in monetary terms, but studies on the costs and benefits all indicate that it is economically rational for farmers to invest their labour in FMNR. The costs are modest (no equipment and little labour), and the benefits are substantial, also helping smallholder farmers adapt to climate change, while sequestering millions of tonnes carbon. As a consequence of FMNR, tree cover has been sustained without external incentives (e.g. food or cash-for-work), an outcome that distinguishes this farmer-driven practice from large-scale tree planting projects where farmers’ stewardship ended when the external incentives ended. Agroforestry landscapes are thus being created at scale due to decisions made by hundreds of thousands of individual farmers. It is hoped that information in this report that shows the clear benefits of FMNR in Niger will encourage policy makers in Africa’s drylands to invest in the promotion of FMNR. This foundational practice must form the backbone of landscape wide initiatives if the ambitious targets of the Great Green Wall, AFR100 and similar ambitious restoration initiatives are to be achieved. FMNR is a low cost sustainable land use management practice with a considerable potential for scaling, which can and must be adopted and scaled immediately.