In the face of biodiversity loss due to agricultural expansion and intensification, agroforestry has been proposed as an environmentally friendly form of agriculture capable of conserving biodiversity while supporting local livelihoods. However, how social drivers related to farmers’ decision-making and ecological processes affect the potential of agroforestry systems to serve as reservoirs for native species diversity and community composition is unclear. This dissertation aims to describe patterns of tree diversity and community composition in coffee (Coffea arabica) agroforestry systems as they compare to surrounding forests, and uncover the social drivers related to farmers’ decision-making and ecological processes giving rise to those patterns. Worldwide, there is an extensive overlap between coffee-growing areas and regions with high species richness and endemism considered biodiversity hotspots. This renders the issue of clarifying the sustainability and conservation value of shade coffee even more urgent. Otherwise, we risk losing important late-succession and conservation concern tree species, and simplifying the structural and floristic composition of mature forests. To uncover how the social factors related to farmers’ decision-making and ecological factors drive tree diversity and community composition in coffee agroforestry systems, a series of empirical studies were conducted based on surveys and field data collected in La Sepultura Biosphere Reserve in Chiapas, Mexico, between 2009-2013. Field research took place in two coffee farming communities within the reserve, where 50 farmers were interviewed, and 31 coffee agroforest sites and 10 forest sites were sampled. Forests were sampled to provide a reference for tree diversity and community composition in the absence of coffee management. Although a higher sample size would have permitted the inclusion of more covariates in statistical analyses without losing statistical power, there is no reason to believe that the results of this dissertation would change if a larger sample size were considered. This is because the magnitude of the effects detected were large and the p-values small, which underscore the robustness of the results of this dissertation. The three chapters in this dissertation correspond to individual studies. Chapter One investigates tree floristic patterns in coffee agroforestry systems and compares them to those in surrounding forests. Findings indicate that although at the landscape level coffee agroforestry systems hold similar tree species richness compared to forests, tree species community composition is significantly distinct. Coffee agroforests had a lower proportion of trees of conservation concern, a higher proportion of pioneer trees, were dominated by Inga spp., harbored lower tree species diversity at the plot level, and were composed of different tree species compared to native forests. This chapter raised questions with regards to whether these results were the result of farmers’ intentional tree selection criteria and preferences, or an unintended consequence of management practices. Chapter Two addressed these questions by examining the use of knowledge by farmers to manage coffee agroforests and the consequences on tree community composition relative to forests. In Chapter Two, results indicate that differences between agroforests and forests are primarily driven by farmers’ manipulation of tree community composition, which occurs according to their beliefs about the benefits and disservices of trees for coffee production. Tree community composition in coffee agroforest is dominated by the trees that farmers prefer and practically void of the trees they dislike as compared to the trees’ natural abundances in forests. These findings are novel and important because they clarify that the community composition changes observed in coffee agroforests are mostly an intentional consequence of management and not a byproduct. Finally, Chapter Three focuses on a subset of trees of particular conservation importance, trees of conservation concern (CC) and typical of old growth or late succession (LS) forests. This chapter investigates how management practices that affect shade tree density, basal area, and the proportion of Inga trees, mediated by land use legacies, affect the proportions of CC and LS trees in coffee agroforests. Findings indicate that management practices that sought to increase the proportion of Inga spp. trees had the largest negative impact on the proportions of trees of LS and CC, but the magnitude of the effects were dependent on land-use legacy. Among farms established on land previously used for pastureland or crop cultivation, the impact of farmers’ tree preferences and selection criteria on LS and CC trees were significantly higher than on farms established on forests without an agricultural history. These findings underscore that farmers’ sharp preference for Inga spp. trees undermines the potential of agroforests to conserve higher proportions of CC and LS trees. The results presented in each chapter of this dissertation allow for a more thorough understanding of the tree diversity patterns conserved in coffee agroforestry systems and the underlying social drivers related to farmers’ decision-making and ecological drivers that generate such patterns. The results of this dissertation seek to contribute new knowledge not only to the scientific community, but also to society so that better policies and strategies be devised that successfully conserve floristic diversity in the biodiverse areas of the world where coffee is cultivated.

MENVSC / Department of Ecology and Resource Management

A modelagem de serviços ecossistêmicos hidrológicos é uma ferramenta auxiliar na tomada de decisões para investimento financeiro em práticas de uso da terra e em projetos para a restauração florestal. Em virtude da necessidade de melhoria no provimento desses serviços ao menor custo de investimento para o Sistema Cantareira, este trabalho teve o objetivo de simular cenários para avaliação de atividades de transição do uso e cobertura da terra e identificação de áreas prioritáriass, considerando critérios ambientais, sociais e políticos. A região do estudo compreende um complexo hidráulico de transposição de bacias dos rios Piracicaba, Capivari e Jundiaí (PCJ) para a bacia do Alto Tietê, que possui a finalidade de abastecimento de água para a região metropolitana de São Paulo. Foram utilizados os modelos InVEST e RIOS, ferramentas compostas por métodos consagrados da literatura científica, como a equação universal da perda de solo e o balanço hídrico de massa em bacias. São modelos baseados na valoração do capital natural, utilizados para a avaliação da exportação de sedimentos e produção de escoamento base, de acordo com o valor de investimento e o custo de atividades, respectivamente. As atividades definidas para transição compreenderam a alteração das áreas agrícolas de pastagem para sistema agroflorestal (silvipastoril), a restauração florestal assistida e a regeneração natural. A diferença entre os cenários foi a adoção das atividades propostas e o montante de recursos a ser aplicado por sub-bacia. Os melhores cenários para redução na exportação de sedimentos foram avaliados em relação à transição na área total de drenagem e para a produção hídrica sazonal. O modelo RIOS demonstrou maior sensibilidade aos custos das atividades de transição e à efetividade no controle da erosão, sendo que, os critérios aplicados para áreas preferenciais demonstraram um bom resultado na priorização das áreas. No modelo InVEST foi possível identificar as sub-bacias que apresentaram maior exportação de sedimentos e os cenários com melhor resultado para a diminuição, identificados como plantio e regeneração. A regeneração demonstrou ser a atividade com melhor benefício, com redução de 33,20% e aumento de 24,10% no escoamento base, quando considerada a área preferencial de transição em APP, declividade até 25% e vertentes de face sul, para a distribuição de áreas pelo modelo. / The modeling of hydrological ecosystem services is an auxiliary tool in decision making for financial investment in land use practices and in forest restoration projects. Due to the need for improvement in the provision of these services at the lowest investment cost for the Cantareira System, this work aimed to simulate scenarios for the evaluation of land use and land cover transition activities and identification of priority areas, with environmental, social and political criteria. The study area comprises a hydraulic complex for the transposition of the Piracicaba, Capivari and Jundiaí (PCJ) river basins into the Alto Tietê basin, which has the purpose of supplying water to the metropolitan region of São Paulo. The InVEST and RIOS models, composed by scientific tools approaches as university soil loss equation and water mass balance in watersheds. They are based on the valuation of natural capital, used for the evaluation of sediment exports and production of base flow, according the investment value and cost of activities, respectively. The activities defined for transition included the change from pasture to agroforestry (agroforestry pasture), assisted forest restoration and natural regeneration. The difference between the scenarios was the adoption of the proposed activities and the amount of resources to be applied in each watershed. The best scenarios for the reduction of sediment exports were evaluated in relation to the transition in the total drainage area and for seasonal water production. The RIOS model showed greater sensitivity to the costs of transition activities and erosion control effectiveness, and the criteria applied to preferential areas showed a good result in the prioritization of the areas. In the InVEST model, it was possible to identify the watersheds that had the highest export of sediments and the scenarios with the best result for the decrease, identified as planting and regeneration. Regeneration was the most favored activity, with a reduction of 33.20% and 24.10% of increase in the base flow, when considering the transition in APP, the slope by 25% and south face slopes as choose criteria to model distribution areas.

Esse estudo teve como objetivo comparar duas formas de manejo de cultivos de banana em relação ao seu potencial de abrigar espécies florestais. Nós assumimos que o registro de espécies florestais utilizando um elemento da matriz mostra que a espécie não evita a matriz totalmente e pode ser capaz de cruzá-la, indicando a importância dessas estruturas para a manutenção de conectividade funcional entre as áreas de hábitat. Foram amostrados 30 cultivos incluindo áreas sob manejo convencional e agroflorestal. Em cada unidade amostral foram realizadas transecções para acessar a proporção de aves florestais, generalistas e de áreas abertas. Variáveis descritoras da estrutura interna e da estrutura da paisagem do entorno dos cultivos foram consideradas para verificar se a avifauna responde à características intrínsecas dos cultivos ou ao contexto de paisagem em que os cultivos estão inseridos. A proporção de espécies florestais foi maior em cultivos agroflorestais (F28;0,001=19,29; p<0,0004), enquanto a proporção de generalistas não apresentou diferença significativa (F28;0,001=0,22; p<0,22) e a de espécies de áreas abertas foi maior em cultivos convencionais (F28;0,001=8,92; p<0,006). Os dois conjuntos de variáveis considerados, isto é, a estrutura interna do cultivo e do entorno deste foram importantes para predizer a proporção de espécies florestais. Embora tenhamos observado o efeito da paisagem na proporção de espécies florestais, salientamos aqui que sistemas convencionais, mesmo em contextos de paisagem similares à sistemas agroflorestais, não apresentaram a mesma proporção de espécies florestais. Esse resultado indica um diferencial de cultivos agroflorestais de banana para a ocorrência de espécies florestais. Em nível de paisagem, a proporção de florestas e consequentemente a diminuição do isolamento entre manchas é o responsável pela presença potencial de espécies em fragmentos. No entanto, em nível de mancha, mesmo esta apresentando um contexto de paisagem favorável para que seja ocupada por espécies de áreas fonte, o mecanismo que influencia a presença das espécies é a elevada estrutura interna dos bananais. / This study aimed to compare two management of banana crops in relation to its potential to host forest bird species. We assume that the record of forest bird species using a matrix element shows that the species does not entirely avoid this area and may be able to cross it, indicating the importance of these structures for the maintenance of functional connectivity between areas of habitat. We sampled 30 areas including crops under conventional and agroforestry management. In each sampling unit we used transects to access the composition and abundance of bird species. Descriptive variables of the internal structure and the structure of the surrounding landscape of crops were considered to determine whether the bird responds to the intrinsic characteristics of the crops or the landscape context in which crops are inserted. The proportion of forest species was higher in agroforestry crops (F28, 0,001 = 19.29, p <0.0004), while the proportion of generalists showed no significant difference (F28, 0,001 = 0.22, p <0.22) and species of open areas was greater in conventional crops (F28, 0,001 = 8.92, p <0.006). The two sets of variables considered, i.e. the internal structure of the crop and of surroundings, were important to predict the proportion of forest birds species. Although we observed the effect of landscape in the proportion of forest species, we note here that conventional systems, even in contexts similar to the landscape agroforestry systems, did not show the same proportion of forest species. This result indicates a upper value of agroforestry crops for the occurrence of forest bird species. At landscape level, the proportion of forests and consequently the lower isolation between patches is responsible for the potential presence of species in fragments. However, at patch level, even it is presenting a landscape context favorable to be occupied by a species of source areas, the mechanism that influences the presence of the species is the high internal structure of the banana plantations.

A pesquisa apresentada nesta tese tem como objetivo realizar uma análise e reflexão sobre as estratégias metodológicas da agroecologia, com o intuito de compreender a forma pela qual lógicas econômicas não capitalistas (camponesa, quilombola e/ou indígena) têm participado e/ou poderiam participar do processo de construção- concepção e execução- deste campo do conhecimento. Numa busca por caminhos que indicassem as formas de equalizar as relações de poder inerentes ao diálogo de saberes e fazeres previsto na teoria agroecológica, optou-se por analisar a comunidade quilombola do bairro Ribeirão Grande -localizada no Vale do Ribeira, Barra do Turvo/SP - e suas experiências de produção agroflorestal e envolvimento com uma associação/cooperativa agroflorestal reconhecida nacional e internacionalmente, a Cooperafloresta. O recorte analítico neste território, portanto, compreende a investigação tanto sobre a comunidade quilombola, quanto sobre as estratégias metodológicas da Cooperafloresta. No decorrer da pesquisa identificou-se a existência de uma tensão entre o saber-fazer quilombola e o saber-fazer agroflorestal. Para compreender o processo de formação deste conflito e analisar as formas de relação estabelecidas no âmbito das experiências agroecológicas, realizou-se: uma análise biográfica da liderança quilombola Nilce de Pontes Pereira do Santos; um histórico e caracterização da comunidade do Ribeirão Grande desde o seu interior; e uma discussão sobre a forma pela qual a Cooperafloresta se constituiu naquele território. A intersecção entre estas três perspectivas de análise nos permitiu estabelecer cinco constatações, que se orientaram, de forma geral, para a identificação da contribuição da geografia à agroecologia . A conclusão desta pesquisa indicou a pertinência da orientação do método agroecológico à apreensão da totalidade da identidade local e da agroecologia enquanto contribuição ao movimento de comunidades rurais não capitalistas. / The research presented in this thesis aims to perform an analysis and reflect on the methodological strategies of agroecology, in order to understand the way in which non­ capitalist economic logic (peasant, Maroon and/or indigenous) have been and/or could be involved in the process - design and execution - of building this field of knowledge. Looking for paths that could indicate means to equalize the power relations inherent in the dialogue of knowledge and practices set out in agroecological theory, we chose to analyze the quilombo community of Ribeirão Grande neighborhood - located in the Vale do Ribeira, Barra do Turvo/SP- and their experience with agroforestry production and involvement with an agroforestry association/cooperative nationally and internationally recognized, Cooperafloresta. The analytical approach in this area therefore includes research on both the quilombo and the methodological strategies of Cooperafloresta. The existence of a tension between the quilombo and the agroforestry know-hows could be identified during the study. Research took place in order to understand the process of formation of this conflict and analyze the forms of relationship established under the agroecological experiences: a biographical analysis of quilombo leader Nilce de Pontes Pereira do Santos; a past history and characterization of Ribeirão Grande community from the inside; and a discussion about how Cooperafloresta has been constituted on that territory. The intersection of these three perspectives of analysis allowed us to establish tive findings, which guided, in general, to identifying the contribution of geography to agroecology. The conclusion of this research indicated the relevance of the guidance of agroecological method to the seizure of all the local identity and of agroecology as a contribution to the movement of rural non-capitalist communities.

Bibliography: leaves 94-98

Graduation date: 1998

The increasing input costs for traditional agriculture has led land owners and producers in search of alternative opportunities to increase on-farm income. Replacing agricultural crops with short rotation woody species such as hybrid poplar trees is a form of agroforestry. The objectives of this project were to evaluate: 1) a suitable planting stock for hybrid poplar, 2) the effect of nitrogen (N) fertilizer application and pruning on hybrid poplar growth and, 3) the response of four hybrid poplar clones to fertilizer application and their suitability in the boreal transition ecoregion of Saskatchewan. <p>Two trials were established near Meadow Lake, Saskatchewan where three stock types (cuttings, root cuttings and rooted plugs) of Walker poplar were planted into former alfalfa and pasture fields. Trees were pruned each spring to remove multiple leaders and fertilized in year 2 with 100 kg N ha-1. The presence of roots on rooted cutting and plug stock types was beneficial in terms of hybrid poplar growth and survival. Trees grown from planting stock without roots had survival rates between 32-37% whereas, the survival of trees with roots at the time of planting ranged from 62-81% after two years of growth. Trees that were planted as a rooted stock were 3.5 to 4.2 times greater in height and 4.0 to 5.6 times greater in root collar diameter than trees planted as an un-rooted stock type. The application of fertilizer N decreased tree volumes by 31% at the Alfalfa site and had no effect on tree growth at the Pasture site. The total amount of fertilizer N recovered by the hybrid poplar trees ranged from 1-3% at the Alfalfa site and 3-5% at the Pasture site. <p>The second study involved planting four clones of hybrid poplar (Hill, Katepwa, Walker and WP-69) at the same two sites and applying fertilizer at rates of 0, 150 and 300 kg N ha-1 the first two years. Following the second growing season, Katepwa and WP-69 clones had the highest tree volumes of 750 and 1147 cm3 of the four clones evaluated. The Walker clone had the poorest survival rates (52-56%) compared to the other three clones (> 90% survival). Foliar N levels were not correlated with tree height at the Alfalfa (p=0.1326) or the Pasture (p=0.1063) sites. The relationship between foliar P concentration and tree height was more pronounced during July at the Alfalfa site with an r2 value of 0.7102. The N:P ratios for foliar tissue decreased with increasing fertilizer N application during August at the Alfalfa site. Foliar N:P ratios were the same among fertilizer and clone treatments at the Pasture site in August. <p>Results from this study suggest that rooted stock types increase the successful establishment of hybrid poplar plantations. However, application of N fertilizer may not increase growth of trees if soil N is adequate. Other soil nutrients need to be measured prior to fertilization to determine what nutrients may be limiting plant growth.

Tropical agroforestry systems are perceived to have the capacity to be resilient to future changes in climate. This study quantifies the response of two tropical agroforestry tree seedlings; Gliricidia sepium (Jacq.) Walp and Cedrela odorata L. to increases in atmospheric concentrations of carbon dioxide (CO2) (800 ppm), temperature (+2°C daytime and +3°C nighttime) and the combined conditions. As well, this study analyzes the microbial community structure and nutrient concentration in response to elevated concentrations of CO2 on tropical silvopastoral soil, conventional pastoral soil and a regenerated forest soil. Both tree species demonstrated very individual responses to the different climate scenerios. While no significant CO2 fertilizer effect was observed in either species the combined treatment demonstrated a significant increase in seedling height for both species. The response of G. sepium to the combined treatment was similar to its response to the temperature treatment which could be a result of achieving the optimal range in temperature for growth. As well, an increase in C:N ratio from G. sepium seedling leaves under the combined treatment indicates the possibility of the nutrient concentration diminishing thereby reducing the role of this species as a provider of high nutrient biomass. The soil microbial community showed very little change in response to elevated concentrations of CO2 and differences in community structure between sites were also negligible. Soil nutrient concentration maintained the best balance over the course of both twelve week incubations for the regenerated forest site followed by the silvopastoral site and lastly the conventional pasture site. The response of soil nutrient concentration to elevated concentrations of CO2 was negligible reflecting the response of the soil microbial community.

The increasing input costs for traditional agriculture has led land owners and producers in search of alternative opportunities to increase on-farm income. Replacing agricultural crops with short rotation woody species such as hybrid poplar trees is a form of agroforestry. The objectives of this project were to evaluate: 1) a suitable planting stock for hybrid poplar, 2) the effect of nitrogen (N) fertilizer application and pruning on hybrid poplar growth and, 3) the response of four hybrid poplar clones to fertilizer application and their suitability in the boreal transition ecoregion of Saskatchewan. <p>Two trials were established near Meadow Lake, Saskatchewan where three stock types (cuttings, root cuttings and rooted plugs) of Walker poplar were planted into former alfalfa and pasture fields. Trees were pruned each spring to remove multiple leaders and fertilized in year 2 with 100 kg N ha-1. The presence of roots on rooted cutting and plug stock types was beneficial in terms of hybrid poplar growth and survival. Trees grown from planting stock without roots had survival rates between 32-37% whereas, the survival of trees with roots at the time of planting ranged from 62-81% after two years of growth. Trees that were planted as a rooted stock were 3.5 to 4.2 times greater in height and 4.0 to 5.6 times greater in root collar diameter than trees planted as an un-rooted stock type. The application of fertilizer N decreased tree volumes by 31% at the Alfalfa site and had no effect on tree growth at the Pasture site. The total amount of fertilizer N recovered by the hybrid poplar trees ranged from 1-3% at the Alfalfa site and 3-5% at the Pasture site. <p>The second study involved planting four clones of hybrid poplar (Hill, Katepwa, Walker and WP-69) at the same two sites and applying fertilizer at rates of 0, 150 and 300 kg N ha-1 the first two years. Following the second growing season, Katepwa and WP-69 clones had the highest tree volumes of 750 and 1147 cm3 of the four clones evaluated. The Walker clone had the poorest survival rates (52-56%) compared to the other three clones (> 90% survival). Foliar N levels were not correlated with tree height at the Alfalfa (p=0.1326) or the Pasture (p=0.1063) sites. The relationship between foliar P concentration and tree height was more pronounced during July at the Alfalfa site with an r2 value of 0.7102. The N:P ratios for foliar tissue decreased with increasing fertilizer N application during August at the Alfalfa site. Foliar N:P ratios were the same among fertilizer and clone treatments at the Pasture site in August. <p>Results from this study suggest that rooted stock types increase the successful establishment of hybrid poplar plantations. However, application of N fertilizer may not increase growth of trees if soil N is adequate. Other soil nutrients need to be measured prior to fertilization to determine what nutrients may be limiting plant growth.