The response of geomorphic systems to disturbance has been a major focus of geographic research. Nevertheless, because the sensitivity of geomorphic systems to external perturbation is complex, the response of those systems is still poorly understood for many agricultural systems in various geographic settings. This study investigates geomorphic sensitivity and soil erosion under traditional slash-and-burn cultivation. The response of soil erosion to this agricultural practice was investigated in selected plots at different stages of cultivation, representing a chronosequence of slash-and-burn cultivation for the study site. Selected physical and hydrological properties were measured in the field or determined in the laboratory from soil samples obtained from the selected plots. Soil erosion was monitored for the selected plots using bounded runoff plots. Finally, the response of soil erosion to slash-and- burn was assessed at the watershed scale by adapting the Revised Universal Soil Loss Equation to local field conditions. The study results showed that soil’s selected physical and hydrological properties differed according to the age of cultivation. In general, soil properties, such as organic matter, aggregate stability, and infiltration, showed signs of deterioration during the cultivation phase and improvement during the fallow stage of slash-and-burn cultivation. These differences in turn resulted in differences in the erodibility of the soil and the response of soil erosion at the plot scale. The soil erosion rate was observed to be higher during the cultivation stage of slash-and-burn cultivation and lower during the fallow stage. The lowest rate of erosion was recorded in natural forest plots. Overall, soil erosion rates were low considering the study site’s mountainous nature. The results of this study suggest that the response of soil erosion under the practice of slash-and burn cultivation could be minimal in a potentially sensitive humid tropical mountainous environment depending on the specific cover produced, the environmental factors, and the specific cultural management, such as cropping and tilling practices. Maintaining adequate ground cover through cropping and fallow management is the key to keeping soil erosion minimal under the practice of slash-and-burn cultivation in the study area. / text

Slash and burn shifting (Chitemene) cultivation has been the dominant traditional land use system in the Miombo woodlands of Northern Zambia. The land use system adopted by farmers depends on the interaction between biophysical and socio- cultural and economical resources available to them. Socio economic resources also include policies, which influence the farmers’ decisions. Despite the so many interventions that have been done and condemnation of this system, this practice of cultivation still persist up to today. It is estimated that Northern Province has lost 35% of its biomass, representing about 43000 km2 of forests land over the past 40 years. The continuation of Chitemene system is in the long term unsustainable. This is because if the rural population continues to grow and if the current trend in Chitemenecontinues, complete deforestation may occur in a few decades. This study tried to investigate the factors that determine this practice in Zambia. The study employed a binomial logit model in order to identify the factors that influence the farmers’ decision to practice chitemene and to quantify the relative importance of these factors. This was employed on data collected from a survey of 90 farmers from Kasama district in the Northern Province of Zambia.</p.> It was hypothesized that the farmers’ behavior is influenced by a complex set of socio economic, demographic, technical, institutional and biophysical factors. Some of the determinants of slash and burn practice found in studies done are structural adjustment programme in Zambia, population growth land tenure system, infrastructure, necessary support services, number of household members, age, gender, education level and amount of available land. It was also hypothesized that the traditional way of life of the people has more influence on the farmers’ decision to practice slash and burn than other factors such as land tenure and even availability of agricultural inputs. This is because despite the so many interventions the practice has continued. Also the older the farmer is in his farming practice and age the more likely he is to practice chitemene. The reason is that farmers usually base their practice on experience and older farmers are a bit conservative and often tend to perpetuate the practice. The other one was that farmers with bigger land area are more likely to practice chitemene than those with less total land area. Farmers with bigger land area have more woodland and therefore more likely to practice. The study revealed from the bivariate analysis results that availability of land increases the chances of the farmer practicing chitemene. It was also shown that non-availability of credit influences farmers’ decision to practice chitemene positively. Lack of money to acquire inputs contributed more to farmers’ decision to practice chitemene. In the econometric analysis, age of the farmer, effect of non-availability of credit facility, effect of household size and influence of tradition had a significant influence on chitemene practice. It was found that the main reason for chitemene practice is lack of money for acquisition of inputs. Policies that facilitate provision of credit and infrastructure development like roads are necessary if slash and burn is to be reduced. This study identified some entry points for policy. Poverty may prevent poor farmers from investing in land conservation due to imperfections in credit markets and high subsistence requirements. So unless the government employs policies that target these factors, there is every reason for the farmers to continue the practice of slash and burn. This study brings to light that practicing of Chitemene depends upon a number of factors that dictate its continued practice. It is imperative that the policy makers and all those involved in agricultural development and policy formulation understand these factors and their relative importance in order to have targeted policies. Moreover although a number of studies have been done on slash and burn and its effects in Zambia, these studies have not analysed the significance of these factors. This study has considered this. Apart from this, it has also contributed to the bulk of research literature on chitemene that might be relevant for future research. / Dissertation (MSc (Agricultural Economics))--University of Pretoria, 2007. / Agricultural Economics, Extension and Rural Development / unrestricted

The history of land utilization in Scandinavia is characterized by two major periods of open landscape. The first one temporal ranged from cal. AD 0-500 and the second one ranged from cal. AD 1200-1900 including the medieval crisis in Scandinavia. Both periods were characterized by animal husbandry and intensive grazing as well as cultivation. However, slash-and-burn-cultivation and hay production on mires and meadows were prevailing during the medieval crisis. These activities significantly altered the concentration of transported organic carbon (OC) from the terrestrial ecosystem to inland waters. Burning and grazing decreased the terrestrial OC and water table, due to reduction of biomass, whereby burning has a greater effect. Biennial scything of mires for hay production reduced the biomass as well, hence resulting in a decreasing water table and peat accumulation. Even though two periods of open landscape has been present in the historical land utilization of Scandinavia, only the latest one resulted in a decreasing OC concentration in surface water in boreal lake. This indicates that especially the slash-and-burn cultivation and hay production on mires are very important components of altering the carbon storage in soils and peat due to lowering the terrestrial OC pool.

Essa pesquisa foi desenvolvida no município de Biguaçu, litoral de Santa Catarina, especificamente na localidade de Três Riachos, e visou compreender o quão sustentáveis são as maneiras com que famílias de agricultores aí residentes conduzem suas vidas em meios rurais, que estão associados a duas práticas particularmente associadas: a agricultura de corte e queima e a produção de carvão. Esses agricultores familiares movimentaram historicamente um sistema social e ecológico do qual estiveram fortemente subsidiados por recursos florestais, um ativo particularmente importante para essas pessoas. De um ponto de vista multidimensional, ancorado pelo conceito de desenvolvimento como liberdade e da capacitação de pessoas em acessarem múltiplos recursos, ou ativos, nos propomos discutir possíveis respostas para as perguntas que seguem: possuem qualidade de vida essas pessoas? São sustentáveis seus meios de vida? Procuramos descrever as particularidades sociais e ecológicas do contexto de estudo através de dados coletados com etnografia e observação participante, confrontá-los com dados secundários e discutindo-os com bibliografias pertinentes. Para tal, levamos em consideração o acesso a cinco tipos de ativos relacionados, capital natural, capital humano, capital financeiro, capital social e capital físico e mais um associado, o capital cultural. Concluiu-se que as características particulares de cada ativo/capital que aumentam ou diminuam a sustentabilidade dessas pessoas são: para o capital natural: a possibilidade de utilização de recursos naturais advindos da própria propriedade da família e a capacidade de regeneração, ou renovação desses recursos naturais; para o capital humano, físico e financeiro: o trabalho excessivo e insalubridades relacionadas às suas atividades, a precariedade da infraestrutura e dos processos produtivos, a falta de conhecimentos para acessarem tecnologias e políticas públicas para melhorar essa infraestrutura; para o capital social: as relações de confiança e reciprocidade entre as pessoas das comunidades, a possibilidade de melhorias das relações de confiança com o público externo; no capital cultural: as características de cuidado dos agricultores que fazem com que eles estabeleçam relações de reciprocidade para com pessoas externas, seus clientes, sendo que para isso, depositam um esforço para que seus produtos sejam de boa qualidade. A busca de meios de vida sustentáveis é a maneira de se criar sistemas sócioecológicos resilientes. A sustentabilidade social e ambiental dessas famílias possuem potenciais positivos e negativos, e que certamente possuem desafios para que sejam reproduzíveis em sistemas sócioecológicos resilientes. A pesquisa contribuiu com o esforço de gerar dados para a compreensão dessa realidade complexa. A gestão de sistemas sociais e ecológicos deve levar em consideração um portfólio de ativos sociais, econômicos, ecológicos, humanos e culturais para que seja possível constituir sistemas sócio ecológicos resilientes. / This research was conducted in the city of Biguacu, Santa Catarina coast, specifically in the town of Três Riachos, and aimed to understand how sustainable are the ways in which families residing farmers lead their lives in rural areas, that are associated with two practices particularly associated with: a cut and burn agriculture and charcoal production. These farmers historically handled a social and ecological system of which were heavily subsidized by forest resources, a particularly important asset for these people. A multidimensional perspective, anchored by the concept of development as freedom and empowerment of people to access multiple resources, or assets, we propose to discuss possible answers to the following questions: have quality of life these people? Are sustainable livelihoods? We try to describe the social and ecological characteristics of the study context through data collected with ethnography and participant observation, confront them with secondary data and discussing them with relevant bibliographies. To this end, we consider access to five types of related assets, natural capital, human capital, financial capital, social capital and physical capital and another associate, the cultural capital. It was concluded that the particular characteristics of each asset / capital that increase or decrease the sustainability of these people are for natural capital: the possible use of natural resources from their own family property and regeneration capacity, or renewal of these resources natural; to the human, physical and financial capital: overwork and? insalubrity related to its activities, poor infrastructure and production processes, the lack of knowledge to access technologies and policies to improve the infrastructure; to social capital: trust relationships and reciprocity between people of the communities, the possibility of improvements in trust with the general public; the cultural capital: the care of characteristics of farmers who make them establish reciprocal relations to external people, your customers, and for that, deposit an effort to make its products are of good quality. The search for sustainable livelihoods is the way to create resilient ecological systems partner. The social and environmental sustainability of these families have positive and negative potentials, and they certainly have challenges that are playable on resilient ecological systems partner. The research contributed to the effort to generate data for the understanding of this complex reality. The management of social and ecological systems must take into account a portfolio of corporate assets, economic, ecological, human and cultural so that you can be resilient ecological systems partner.

Essa pesquisa foi desenvolvida no município de Biguaçu, litoral de Santa Catarina, especificamente na localidade de Três Riachos, e visou compreender o quão sustentáveis são as maneiras com que famílias de agricultores aí residentes conduzem suas vidas em meios rurais, que estão associados a duas práticas particularmente associadas: a agricultura de corte e queima e a produção de carvão. Esses agricultores familiares movimentaram historicamente um sistema social e ecológico do qual estiveram fortemente subsidiados por recursos florestais, um ativo particularmente importante para essas pessoas. De um ponto de vista multidimensional, ancorado pelo conceito de desenvolvimento como liberdade e da capacitação de pessoas em acessarem múltiplos recursos, ou ativos, nos propomos discutir possíveis respostas para as perguntas que seguem: possuem qualidade de vida essas pessoas? São sustentáveis seus meios de vida? Procuramos descrever as particularidades sociais e ecológicas do contexto de estudo através de dados coletados com etnografia e observação participante, confrontá-los com dados secundários e discutindo-os com bibliografias pertinentes. Para tal, levamos em consideração o acesso a cinco tipos de ativos relacionados, capital natural, capital humano, capital financeiro, capital social e capital físico e mais um associado, o capital cultural. Concluiu-se que as características particulares de cada ativo/capital que aumentam ou diminuam a sustentabilidade dessas pessoas são: para o capital natural: a possibilidade de utilização de recursos naturais advindos da própria propriedade da família e a capacidade de regeneração, ou renovação desses recursos naturais; para o capital humano, físico e financeiro: o trabalho excessivo e insalubridades relacionadas às suas atividades, a precariedade da infraestrutura e dos processos produtivos, a falta de conhecimentos para acessarem tecnologias e políticas públicas para melhorar essa infraestrutura; para o capital social: as relações de confiança e reciprocidade entre as pessoas das comunidades, a possibilidade de melhorias das relações de confiança com o público externo; no capital cultural: as características de cuidado dos agricultores que fazem com que eles estabeleçam relações de reciprocidade para com pessoas externas, seus clientes, sendo que para isso, depositam um esforço para que seus produtos sejam de boa qualidade. A busca de meios de vida sustentáveis é a maneira de se criar sistemas sócioecológicos resilientes. A sustentabilidade social e ambiental dessas famílias possuem potenciais positivos e negativos, e que certamente possuem desafios para que sejam reproduzíveis em sistemas sócioecológicos resilientes. A pesquisa contribuiu com o esforço de gerar dados para a compreensão dessa realidade complexa. A gestão de sistemas sociais e ecológicos deve levar em consideração um portfólio de ativos sociais, econômicos, ecológicos, humanos e culturais para que seja possível constituir sistemas sócio ecológicos resilientes. / This research was conducted in the city of Biguacu, Santa Catarina coast, specifically in the town of Três Riachos, and aimed to understand how sustainable are the ways in which families residing farmers lead their lives in rural areas, that are associated with two practices particularly associated with: a cut and burn agriculture and charcoal production. These farmers historically handled a social and ecological system of which were heavily subsidized by forest resources, a particularly important asset for these people. A multidimensional perspective, anchored by the concept of development as freedom and empowerment of people to access multiple resources, or assets, we propose to discuss possible answers to the following questions: have quality of life these people? Are sustainable livelihoods? We try to describe the social and ecological characteristics of the study context through data collected with ethnography and participant observation, confront them with secondary data and discussing them with relevant bibliographies. To this end, we consider access to five types of related assets, natural capital, human capital, financial capital, social capital and physical capital and another associate, the cultural capital. It was concluded that the particular characteristics of each asset / capital that increase or decrease the sustainability of these people are for natural capital: the possible use of natural resources from their own family property and regeneration capacity, or renewal of these resources natural; to the human, physical and financial capital: overwork and? insalubrity related to its activities, poor infrastructure and production processes, the lack of knowledge to access technologies and policies to improve the infrastructure; to social capital: trust relationships and reciprocity between people of the communities, the possibility of improvements in trust with the general public; the cultural capital: the care of characteristics of farmers who make them establish reciprocal relations to external people, your customers, and for that, deposit an effort to make its products are of good quality. The search for sustainable livelihoods is the way to create resilient ecological systems partner. The social and environmental sustainability of these families have positive and negative potentials, and they certainly have challenges that are playable on resilient ecological systems partner. The research contributed to the effort to generate data for the understanding of this complex reality. The management of social and ecological systems must take into account a portfolio of corporate assets, economic, ecological, human and cultural so that you can be resilient ecological systems partner.

Essa pesquisa foi desenvolvida no município de Biguaçu, litoral de Santa Catarina, especificamente na localidade de Três Riachos, e visou compreender o quão sustentáveis são as maneiras com que famílias de agricultores aí residentes conduzem suas vidas em meios rurais, que estão associados a duas práticas particularmente associadas: a agricultura de corte e queima e a produção de carvão. Esses agricultores familiares movimentaram historicamente um sistema social e ecológico do qual estiveram fortemente subsidiados por recursos florestais, um ativo particularmente importante para essas pessoas. De um ponto de vista multidimensional, ancorado pelo conceito de desenvolvimento como liberdade e da capacitação de pessoas em acessarem múltiplos recursos, ou ativos, nos propomos discutir possíveis respostas para as perguntas que seguem: possuem qualidade de vida essas pessoas? São sustentáveis seus meios de vida? Procuramos descrever as particularidades sociais e ecológicas do contexto de estudo através de dados coletados com etnografia e observação participante, confrontá-los com dados secundários e discutindo-os com bibliografias pertinentes. Para tal, levamos em consideração o acesso a cinco tipos de ativos relacionados, capital natural, capital humano, capital financeiro, capital social e capital físico e mais um associado, o capital cultural. Concluiu-se que as características particulares de cada ativo/capital que aumentam ou diminuam a sustentabilidade dessas pessoas são: para o capital natural: a possibilidade de utilização de recursos naturais advindos da própria propriedade da família e a capacidade de regeneração, ou renovação desses recursos naturais; para o capital humano, físico e financeiro: o trabalho excessivo e insalubridades relacionadas às suas atividades, a precariedade da infraestrutura e dos processos produtivos, a falta de conhecimentos para acessarem tecnologias e políticas públicas para melhorar essa infraestrutura; para o capital social: as relações de confiança e reciprocidade entre as pessoas das comunidades, a possibilidade de melhorias das relações de confiança com o público externo; no capital cultural: as características de cuidado dos agricultores que fazem com que eles estabeleçam relações de reciprocidade para com pessoas externas, seus clientes, sendo que para isso, depositam um esforço para que seus produtos sejam de boa qualidade. A busca de meios de vida sustentáveis é a maneira de se criar sistemas sócioecológicos resilientes. A sustentabilidade social e ambiental dessas famílias possuem potenciais positivos e negativos, e que certamente possuem desafios para que sejam reproduzíveis em sistemas sócioecológicos resilientes. A pesquisa contribuiu com o esforço de gerar dados para a compreensão dessa realidade complexa. A gestão de sistemas sociais e ecológicos deve levar em consideração um portfólio de ativos sociais, econômicos, ecológicos, humanos e culturais para que seja possível constituir sistemas sócio ecológicos resilientes. / This research was conducted in the city of Biguacu, Santa Catarina coast, specifically in the town of Três Riachos, and aimed to understand how sustainable are the ways in which families residing farmers lead their lives in rural areas, that are associated with two practices particularly associated with: a cut and burn agriculture and charcoal production. These farmers historically handled a social and ecological system of which were heavily subsidized by forest resources, a particularly important asset for these people. A multidimensional perspective, anchored by the concept of development as freedom and empowerment of people to access multiple resources, or assets, we propose to discuss possible answers to the following questions: have quality of life these people? Are sustainable livelihoods? We try to describe the social and ecological characteristics of the study context through data collected with ethnography and participant observation, confront them with secondary data and discussing them with relevant bibliographies. To this end, we consider access to five types of related assets, natural capital, human capital, financial capital, social capital and physical capital and another associate, the cultural capital. It was concluded that the particular characteristics of each asset / capital that increase or decrease the sustainability of these people are for natural capital: the possible use of natural resources from their own family property and regeneration capacity, or renewal of these resources natural; to the human, physical and financial capital: overwork and? insalubrity related to its activities, poor infrastructure and production processes, the lack of knowledge to access technologies and policies to improve the infrastructure; to social capital: trust relationships and reciprocity between people of the communities, the possibility of improvements in trust with the general public; the cultural capital: the care of characteristics of farmers who make them establish reciprocal relations to external people, your customers, and for that, deposit an effort to make its products are of good quality. The search for sustainable livelihoods is the way to create resilient ecological systems partner. The social and environmental sustainability of these families have positive and negative potentials, and they certainly have challenges that are playable on resilient ecological systems partner. The research contributed to the effort to generate data for the understanding of this complex reality. The management of social and ecological systems must take into account a portfolio of corporate assets, economic, ecological, human and cultural so that you can be resilient ecological systems partner.

"Slash-and-burn" agriculture, or shifting cultivation, is perceived by many to be the leading cause of land degradation in tropical forests. Performed mainly by resource-poor farmers, shifting cultivation is the most widespread form of agriculture in the tropics. Concern over its environmental impacts has led to calls throughout the twentieth century for alternatives by policy-makers and development planners. This study employs a constructivist framework, post-colonial perspectives, and rhetorical methods to understand the images which support such assertions regarding shifting cultivation, primarily in policy-oriented depictions. Elements of Kenneth Burke's "dramatistic" method are used, including the analysis of hierarchies which structure discourse, and pentadic analysis. / Ph. D.

Land-clearing fires set by settlers in the Brazilian Amazon give rise to large scale wildfires that threaten mature forests, agricultural plantations, and settlement areas. Our purpose is to examine labor devoted to fire prevention (firebreak establishment) and burning for crop production for subsistence smallholders in the Tapajós National Forest in Pará, Brazil. Both the decision to engage in each activity and the scale of the activity are examined. A household model addressing decision-making under risk is estimated using survey data from 220 households. We find economic variables such as the opportunity cost of household time, market conditions, and the hiring wage to be important predictors of both decisions (often these are more important than household or demographic considerations), as is household reliance on standing forest resources for non-timber products. We also find that the involvement of NGOs and the government plays an important role in encouraging fire prevention behavior. Our results provide support for programs that emphasize economic parameters and for considering smallholder productivity in policies that target accidental fire prevention or reduction in burning activity. / Master of Science

A presente pesquisa interessa-se em fazer uma análise aprofundada do Direito nascido com o advento da Modernidade, partindo da hipótese de que o Direito Pós-Moderno, embora se auto-proclame como defensor da diversidade, por ainda estar atrelado àquele modelo de legalidade calcado principalmente no positivismo jurídico, passa por uma grave crise, uma vez que, ao excluir regras costumeiras, elimina na prática muitas das possibilidades de aceitação e inclusão do heterogêneo. A exclusão do diferente, do heterogêneo, do \"outro\" contrário à lógica capitalista se torna ainda mais evidente quando normas jurídicas embebidas de conhecimentos científicos ao serem orientadas a regular comportamentos de grupos sociais regulados por regras costumeiras, acabam por invalidá-las, tornando igualmente inexistentes os saberes tradicionais nelas contidos. A fim de melhor compreender esta problemática, entre os diversos direitos que compõem o espectro da Pós- Modernidade, foi escolhido o direito socioambiental como ícone que integra a tutela da diversidade social, cultural e natural. Para tanto, esta pesquisa pretende, através de um Estudo de Caso, verificar as conseqüências relacionadas à possibilidade da Comunidade Remanescente de Quilombo de Ivaporunduva, cuja diferença é tutelada juridicamente como patrimônio cultural brasileiro, continuar a cultivar seus alimentos de forma tradicional, diante da imposição, em caráter universal e geral, de normas jurídicas ambientais infraconstitucionais, em específico, o Código Florestal e a Lei da Mata Atlântica, ainda portadoras de estudos científicos realizados aos moldes racionalidade moderna. Os procedimentos metodológicos se basearam na obra de Boaventura de Souza Santos. Já as técnicas de coleta de dados que foram aplicadas são: observação e roteiro de entrevista semi-estruturado. A análise dos resultados foi feita por meio da técnica de triangulação de dados. Dos resultados obtidos, constata-se 1) a sustentabilidade da roça de coivara; 2) a diminuição da prática da coivara pela comunidade de Ivaporunduva que contribuiu para a) compra de seus alimentos no supermercado, b) aumento de obesidade e desnutrição nesta população, c) intensificação da agricultura e perda da sustentabilidade do sistema, d) ineficácia jurídica e social das normas jurídicas analisadas. A presente pesquisa não propõe uma conclusão fechada desta temática, mas sugere a necessidade de diálogo de saberes para permissão ou não da prática da agricultura de corte e queima, para que se consiga a partir de uma justiça cognitiva, alcançar a almejada justiça social. / This research aims at developing a thorough analysis of the Right that arose with modernity. Based on the hypothesis that even though Post-Modern Right autodenominates itself the advocate of diversity, it is still tied to the legality model of judicial positivism. The Right is ongoing an important crises, and at the time that eliminates customary rules, eliminates several possibilities of acceptance and inclusion of heterogeneity. The exclusion of \"difference/diversity\", of the \"heterogeneous\", of the \"otherness\", is completely opposite to the capitalist logic. This is even more evident when judicial rules embedded in scientific knowledge are targeted to regulate social groups\' behaviors, and end-up invalidating them and eliminating the traditional knowledge embedded in those customary rules. In order to better understand this issue, this research analyzed the tutelage of social, cultural and natural diversity, by means of socio-environmental right, chosen from several rights that compound post-modernity. In order to do so, this case study verifies the consequences related to the possibility of remnants of Quilombola Community, which \"difference/diversity\" is trusted as a Brazilian Cultural Patrimony, continue cultivating their food in a traditional way, facing the universal and general imposition of infraconstitutional environmental legislation, namely, The Brazilian Forestry Code (Código Florestal Brasileiro) and The Atlantic Rain Forest Law (Lei da Mata Atlântica), constituted from scientific studies based on modern rationality thoughts. The methodology and foundation of this study were Boaventura de Sousa Santos\' theoretical work. The data collection was carried out by means of several techniques, like: observation, and semi-structured interviews. The data analysis was carried out by means of data triangulation. From the results obtained in this study it is possible to verify: 1) the sustainability of slash and burn agriculture according to traditional knowledge; 2) the decrease of slash and burn agriculture practice in Ivaporunduva Community leading to a) purchase of food from local supermarkets, b) increase of obesity and malnutrition in community members, c) agriculture intensification and loss of their system\'s sustainability, d) judicial and social inefficiency of the legislation analyzed in this study. The intention of this research is not to propose a final conclusion of this issue, but to suggest the need of an active dialog between traditional and scientific knowledge in order to determine if slash and burn agriculture will be allowed or prohibited as a practice for this community, looking to achieve by means of a cognitive justice, the long expected social justice.

CoordenaÃÃo de AperfeiÃoamento de Pessoal de NÃvel Superior / The objective was to assess the changes promoted in the stocks and flows of C and N from the soil by farming systems agroforestry (agrosilvipasture - AGP and silvipasture - SILV) and traditional (TR), compared to natural vegetation of Caatinga (VN), after 13 years, the experiment was installed on a typical Ortic Chromic Luvisol, the city of Sobral, CearÃ. Soil samples were collected at depths 0-6, 6-12, 12-20, 20-40 and 40-60 cm, relief in four replicates per. Was determined by the total carbon carbon (TOC); total nitrogen (NT) and bulk density. The gas flow was measured using an analyzer in the field of O2, CO2, NO / NO x and SO 2 (UNIGAS Eurotron 3000). To this end, were used for still cameras based on galvanized steel and PVC cover installed in the field. The sampling was done in three replicates, considering the relief plan, convex and concave in each study situation. For each determination were performed triplicate, totaling nine chambers for relief. Soil samples were collected for determination of soil bulk density (Ds) and particle (Dp) and gravimetric moisture (Ug), which allowed the calculation of total porosity (Pt) and the pore space filled with water (EPPA). Among the agroforestry systems studied, the silvipasture, long-term, promoted greater reductions in C stocks and N, the system promoted agrossilvipastroil lower losses and represents a sustainable alternative to sequestration of soil C and N in the Brazilian semi-arid conditions. The traditional cropping system provided a reduction of 58.87 and 9.57 (Mg ha-1), which meant, a reduction of 6.5 and 1.06 (Mg ha-1), for those of TOC and TN, respectively. These results demonstrate the inadequacy of this system for the Brazilian semi-arid conditions. The concave topography (AGP) and flat (SILV) showed the highest values of TOC. For NT the concave shape (VN, AGP, and SILV) showed the highest values. Flows of C-CO2 varied with the time, AGP and SILV being similar to NV in the wet season, while in the dry season are higher. The TR has a different behavior, being higher during the wet season and similar to AGP and SILV in the dry. The flow behavior of NO present without a tendency similar to C-CO2: AGP and SILV presents similar to each other in the wet season, but smaller than VN. During the dry SILV and VN are larger than AGP. In TR NO was not detected in the two periods. The convex shape of relief TR system showed the highest values of C-CO2 fluxes in the wet season. In the dry season were found higher values of C-CO2 flows in AGP, SILV and RT, compared to NV flat terrain. Soil moisture was the variable most correlated with the fluxes of NO, what might be observed in systems SILV and AGP and VN convex reliefs. / Objetivou-se avaliar as alteraÃÃes promovidas nos estoques e fluxos de C e N do solo por sistemas agrÃcolas agroflorestais (Agrossilvipastoril â AGP e Silvipastoril â SILV) e tradicional (TR), comparativamente à vegetaÃÃo natural de Caatinga (VN), apÃs 13 anos, em experimento instalado sobre um Luvissolo CrÃmico Ãrtico tÃpico, no municÃpio de Sobral, CearÃ. Amostras de solo foram coletadas nas profundidades de 0-6, 6-12, 12-20, 20-40 e 40-60 cm, em quatro repetiÃÃes, considerando os relevos plano, convexo e cÃncavo em cada situaÃÃo de estudo. Nestas amostras foram determinados o carbono orgÃnico total do solo (COT), nitrogÃnio total (NT), densidades do solo (Ds) e de partÃcula (Dp) e a umidade gravimÃtrica (Ug), o que possibilitou o cÃlculo da porosidade total (Pt) e o espaÃo poroso preenchido por Ãgua (EPPA). O fluxo dos gases foi quantificado no campo utilizando um analisador de O2, CO2, NO/NOX e SO2 (UnigÃs Eurotron 3000). Para tanto, foram utilizadas cÃmaras estÃticas com base de aÃo galvanizado e tampa de PVC instaladas no campo em triplicatas, totalizando nove cÃmaras por relevo. Entre os sistemas agroflorestais estudados, o silvipastoril, em longo prazo, promoveu maiores reduÃÃes nos estoques de C e N, enquanto que agrossilvipastoril promoveu menores perdas, representando uma alternativa sustentÃvel para o sequestro de C e N do solo nas condiÃÃes semiÃridas brasileira. O sistema de cultivo tradicional (TR) apresentou reduÃÃo no perÃodo 13 anos de 58,87 e 9,57 Mg ha-1 (6,5 e 1,06 Mg ha-1 ano-1) dos estoques de COT e NT, respectivamente, o que comprova a nÃo adequaÃÃo deste sistema para as condiÃÃes semiÃridas brasileiras. Os relevos cÃncavo (AGP) e plano (SILV) apresentaram os maiores valores de estoques de COT, enquanto que para o NT, a forma cÃncava apresentou os maiores valores, no caso VN, AGP e SILV. Os fluxos de C-CO2 variaram com a Ãpoca, sendo AGP e SILV semelhantes à VN no perÃodo Ãmido, enquanto no perÃodo seco estes mesmos sistemas foram maiores. O TR apresenta comportamento diferenciado, sendo maior no perÃodo Ãmido e semelhante ao AGP e SILV no seco. Os fluxos de NO apresentaram comportamento com tendÃncia diferente do C-CO2: AGP e SILV apresentaram-se semelhantes entre si no perÃodo Ãmido, porÃm menores que VN. No perÃodo seco, SILV e VN foram maiores que AGP. No TR, o NO nÃo foi detectado nos dois perÃodos. O relevo convexo no TR apresentou os maiores valores de fluxos de C-CO2 no perÃodo Ãmido. No perÃodo seco foram encontrados maiores valores de fluxos de C-CO2 em AGP, SILV e TR em relaÃÃo à VN no relevo plano. A umidade do solo foi a variÃvel que mais se correlacionou com os fluxos de NO, o que pÃde ser observado nos sistemas SILV e AGP e na VN relevos convexos.