The Argentine Pampa is a global producer of maize (Zea mays L.) and soybean [Glycine max L. (Merr.), however agricultural practices have caused severe soil degradation and amplified greenhouse gas (GHG) production rates. This study presents the effects of maize-legume intercrops compared with maize and soybean sole crops on GHG production rates and soil physical properties over two field seasons. It also presents the results from a laboratory study in which GHGs were quantified from soils amended with maize and soybean crop residues. In the field study, soil organic carbon (SOC) concentrations were significantly greater (p<0.05) in the maize sole crop and intercrops, whereas soil bulk density was significantly lower in the intercrops and as a consequence soil infiltration was higher. Soil total nitrogen (TN) concentrations were not significantly different between treatments. Soil CO2 production rates were significantly greater in the maize sole crop but did not differ significantly for N2O. However, over the two field seasons both trace gases showed a general trend of greater production rates in the maize sole crop followed by the soybean sole crop. Linear regression between soil GHGs and soil temperature or volumetric soil moisture accounted for up to 51% of the variability in soil CO2 production rates and 60% of the soil N2O production rates. In the laboratory study, soil GHG production rates varied between treatments and between residue addition for both CO2 and N2O but varied only narrowly between treatments and experiments for CH4. Results from this study provided further insight into the effect of agroecosystem management practices on GHG production rates and soil physical and chemical characteristics, and contributed to improving our understanding of optimal agroecosystem design.

Kyoto University (京都大学) / 0048 / 新制・課程博士 / 博士(農学) / 甲第19044号 / 農博第2122号 / 新制||農||1032 / 31995 / 京都大学大学院農学研究科地域環境科学専攻 / (主査)教授 縄田 栄治, 教授 舟川 晋也, 教授 白岩 立彦 / 学位規則第4条第1項該当

The Argentine Pampa is a global producer of maize (Zea mays L.) and soybean [Glycine max L. (Merr.), however agricultural practices have caused severe soil degradation and amplified greenhouse gas (GHG) production rates. This study presents the effects of maize-legume intercrops compared with maize and soybean sole crops on GHG production rates and soil physical properties over two field seasons. It also presents the results from a laboratory study in which GHGs were quantified from soils amended with maize and soybean crop residues. In the field study, soil organic carbon (SOC) concentrations were significantly greater (p<0.05) in the maize sole crop and intercrops, whereas soil bulk density was significantly lower in the intercrops and as a consequence soil infiltration was higher. Soil total nitrogen (TN) concentrations were not significantly different between treatments. Soil CO2 production rates were significantly greater in the maize sole crop but did not differ significantly for N2O. However, over the two field seasons both trace gases showed a general trend of greater production rates in the maize sole crop followed by the soybean sole crop. Linear regression between soil GHGs and soil temperature or volumetric soil moisture accounted for up to 51% of the variability in soil CO2 production rates and 60% of the soil N2O production rates. In the laboratory study, soil GHG production rates varied between treatments and between residue addition for both CO2 and N2O but varied only narrowly between treatments and experiments for CH4. Results from this study provided further insight into the effect of agroecosystem management practices on GHG production rates and soil physical and chemical characteristics, and contributed to improving our understanding of optimal agroecosystem design.

京都大学 / 0048 / 新制・課程博士 / 博士(農学) / 甲第19044号 / 農博第2122号 / 新制||農||1032(附属図書館) / 学位論文||H27||N4926(農学部図書室) / 31995 / 京都大学大学院農学研究科地域環境科学専攻 / (主査)教授 縄田 栄治, 教授 舟川 晋也, 教授 白岩 立彦 / 学位規則第4条第1項該当 / Doctor of Agricultural Science / Kyoto University / DFAM

Este trabalho objetivou pesquisar a relação da temperatura de superfície (LST) e do estoque de carbono no solo (ECS) com os diferentes tipos de uso e cobertura do solo (UCT). Sabe-se que tais parâmetros podem ser influenciados pelas atividades antrópicas, podendo afetar a integridade do agroecossistema (IAG) da bacia do Rio Corumbataí (BRC). Entende-se por IAG, a capacidade de manutenção de suas propriedades \"primitivas\" e prestação de serviços ecossistêmicos à sociedade. Para alcançar o objetivo proposto, a dinâmica de UCT foi mapeada, a partir da classificação de imagens do satélite Landsat e fotografias aéreas, dos anos de 1962 a 2011. A LST foi obtida por técnicas de sensoriamento remoto, utilizando a banda termal do sensor TM (Thematic Mapper) do Landsat, para os anos de 1985, 1990, 1995, 1999, 2002 e 2011. A análise do ECS foi feita a partir da coleta de amostras de solo, em diferentes UCT: mata nativa, cana-de-açúcar, pastagem e fruticultura, na profundidade de 0-10 e 10-20 cm. Os resultados indicaram que a LST e os ECS da área de estudo são influenciados pelo UCT e pelo manejo das culturas. Verificou-se ainda que algumas políticas agrícolas, adotadas no período de 1962 a 2011, influenciaram a dinâmica de UCT e, consequentemente, a capacidade do agroecossistema da BRC no fornecimento de serviços ecossistêmicos e também geraram custos ambientais. A abordagem interdisciplinar adotada neste trabalho, com o emprego das geotecnologias, mostrou ser capaz de avaliar a integridade do agroecossistema da BRC, podendo subsidiar o planejamento de uso do solo visando a maximizar a relação benefício/custo das atividades antrópicas, considerando a LST e o ECS. Tal abordagem pode ser aplicada em diferentes áreas do conhecimento para a análise da sustentabilidade e integridade ambiental dos agroecossistemas. / In this work, the aim was search the relationship between both surface temperature (LST) and soil organic carbon (SOC) with several sort of land use cover (LUC). We know such a parameters can be influenced by anthropic activities, it can affects the Corumbataí River basin (CRB) agro ecosystem integrity (AGI). AGI means, the capacity of both maintenance of its \"primitive\" properties and supplies public ecosystem service. Reaching the proposed goal, the LUC dynamic was mapping through both Landsat-TM image classification and aerial photography from 1962 to 2011. The LST has been obtained by remote sensing technique through Lansat-TM thermal band to the years 1985, 1990, 1995, 1999, 2002 and 2011. The ECS analyze was carried out by soil sample collected in different type of LUC: forest native, sugar cane, pasture and orchard, in the 0-10 and 10-20 cm depths. The results have indicated both the BRC of the LST and SOC are influenced by both together LUC and crop tillage. Furthermore, some agricultural policy adopted during from 1962 to 2011 influenced the LUC dynamic, thus the CRB agro ecosystem capacity of supply agro ecosystem services as well as provided environmental cost. The interdisciplinary approach employed, with the use of geotechnologies, has shown to be able to assessment the CRB agro ecosystem integrity, it can supports the LUC planning in order to maximize the benefit/cost ratio anthropic activities, considering both the LST and ECS. Such an approach can be applied in several knowledge areas to evaluation of sustainability and agro ecosystem environmental integrity.

Submitted by Elaine Lucia (lucia.elaine@live.com) on 2015-06-30T19:21:57Z No. of bitstreams: 1 Dissertação - Francisneide de Sousa Lourenço.pdf: 15922986 bytes, checksum: e2432fcb423205c538a19146ab0ab9b4 (MD5) / Approved for entry into archive by Divisão de Documentação/BC Biblioteca Central (ddbc@ufam.edu.br) on 2015-07-01T13:46:26Z (GMT) No. of bitstreams: 1 Dissertação - Francisneide de Sousa Lourenço.pdf: 15922986 bytes, checksum: e2432fcb423205c538a19146ab0ab9b4 (MD5) / Approved for entry into archive by Divisão de Documentação/BC Biblioteca Central (ddbc@ufam.edu.br) on 2015-07-01T14:25:24Z (GMT) No. of bitstreams: 1 Dissertação - Francisneide de Sousa Lourenço.pdf: 15922986 bytes, checksum: e2432fcb423205c538a19146ab0ab9b4 (MD5) / Made available in DSpace on 2015-07-01T14:25:24Z (GMT). No. of bitstreams: 1 Dissertação - Francisneide de Sousa Lourenço.pdf: 15922986 bytes, checksum: e2432fcb423205c538a19146ab0ab9b4 (MD5) Previous issue date: 2010-08-03 / CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Family agriculture, object of this study, still follows the traditional pattern of cultivation, occurring even in a town close to Manaus, capital of the state, and although there is a close relationship with the consumer market, located in the town of Itacoatiara. To arrive at these results, the research used the case study method, with a systemic and holistic approach, based on Morin, because it allows the research has a critical view of reality and the deep study of multiple cases of family farming in the Amazon presents. Farmers in the community of São João do Araçá not suffer great hegemonic influence of the capitalist system of agribusiness in relation to land use and management of natural resources. Harvest is practiced sustainably, hunting, fishing, harvesting of plant resources extractive, such as firewood and for house construction, medicines and food are removed only enough for family use. Agriculture is still held priority to meet the basic needs of the family unit, being sold only the surplus. This form of land use permits regeneration of resources, especially land, is still used as a "resting", ie the rest of the soil to recover its fertility. The presence of mature poultry is an indicator of this type of management because it proves that the land use is not intensive and which are small areas used for agriculture. The workmanship is basically family and social relations of work as task force, partnership and half remain strong both in collective activities related to the community and in their agricultural activities in their agroecosystems. To arrive at these results, the research used the case study method, with a systemic and holistic approach, based on Morin, because it allows the research has a critical view of reality based on the study of the complexity of multiple instances of that family Amazon has. / A agricultura familiar, objeto deste estudo, ainda segue o sistema tradicional de cultivo, mesmo ocorrendo em uma localidade próxima a Manaus, capital do Estado, e ainda que haja uma relação estreita com o mercado de consumo, localizado na sede do município de Itacoatiara. Os agricultores da comunidade São João do Araçá compõem uma população de resistência à influência do sistema capitalista hegemônico do agronegócio no que se refere ao uso da terra e ao manejo de seus recursos naturais. O extrativismo é praticado de forma a atender somente às suas necessidades básicas; a caça, a pesca, a coleta dos recursos vegetais extrativistas, como madeira para lenha e para construção de casas, os remédios e os alimentos são retirados em quantidade suficiente para uso da família em primeiro lugar, e uma pequena parte de alguns produtos são comercializados. A agricultura ainda é realizada com vistas a atender prioritariamente à família na unidade familiar, sendo comercializado apenas o excedente. Essa forma de uso da terra permite a regeneração dos recursos, especialmente do solo, visto que é utilizado o “pousio”, ou seja, o descanso do solo para recuperar sua fertilidade. A presença de capoeira madura é um indicador desse tipo de manejo, pois comprova que o uso do solo não é intensivo e que são utilizadas pequenas áreas para agricultura. A mão-de-obra é basicamente familiar, e as relações sociais de trabalho como- mutirão, parceria e a meia permanecem fortes tanto nas atividades coletivas relacionados à comunidade quanto em suas atividades agrícolas em seus agroecossistemas. Para chegar a esses resultados, a pesquisa utilizou o método Estudo de caso, com uma abordagem sistêmica e holística, baseada em Morin, pois permite que a pesquisa tenha uma visão crítica da realidade baseada no estudo da complexidade dos múltiplos casos que a agricultura familiar da Amazônia apresenta.

Made available in DSpace on 2015-09-25T12:20:50Z (GMT). No. of bitstreams: 1 PDF - Mayara Karla Dantas da Silva.pdf: 2153011 bytes, checksum: 2ae70001971a2a11d959861bbae4fe47 (MD5) Previous issue date: 2013-03-19 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / This work is part of a larger research project called "Studies Network Systems and Research in Sustainability Indicators for Agroecosystems Based Practices in Family Farming and Agriculture Based on the Principles of Green Revolution in Northeast Brazil" and deals with the adaptation and application of MESMIS model - Marco Evaluation Systems Natural Resources Management Incorporating Sustainability Indicators (1995), in the municipality of Pedras de Fogo, south coast of Paraiba, in order to assess the sustainability index in cassava production, based on agriculture family, as social actors. We know that sustainable development appears as a new concept in processing, generating discussion on the basis of little progress in practical terms. From this perspective, instruments have been created in order to change this reality. It is believed that the indicators are methods that help evaluate and communicate the processes present. The MESMIS, model evaluation indicator facing rural contexts, has been understood as an alternative to overcome the barrier merely theoretical and classificatory, pointing to different parts of a management system. From this perspective, the method was applied transversely into six family units, three basic traditional and three alternative basis, the settlement New Dawn in Pedras de Fogo. Were created in a participatory nine indicators of sustainability compounds (Water Resources, Soil Quality, Management, Diversity, Work and their relations, Participation, Self-Management, Economic Situation, Change and Innovation), quantified from primary data collected through interviews, questionnaires and field observations, which enabled detailing the agroecosystems, determine critical points and noted that although culture is a flexible alternative agricultural practices, traditional management techniques are used frequently, due mainly to the lack of knowledge agroecological . Still, the group of agroecosystems based on alternative crop production, presented best feature, from the point of view of sustainability, in social, economic and environmental, as compared to the group of agroecosystems based on conventional production. / Este trabalho faz parte de uma pesquisa maior, denominado Rede de Estudos e Pesquisas em Sistemas de Indicadores de Sustentabilidade para Agroecossistemas Baseados em Práticas de Agricultura Familiar e da Agricultura Baseadas nos Princípios da Revolução Verde no Nordeste Brasileiro e trata da primeira adaptação e aplicação do modelo MESMIS Marco para Avaliação de Sistemas de Manejo de Recursos Naturais Incorporando Indicadores de Sustentabilidade (1995), no estado da Paraíba. O método foi aplicado no município de Pedras de Fogo, litoral sul do estado, com o objetivo de avaliar o índice de sustentabilidade na produção de mandioca, baseada na agricultura familiar, a partir da percepção dos atores sociais. Sabe-se que o desenvolvimento sustentável aparece como um conceito novo, em transformação, gerando discussões em função dos poucos avanços em termos práticos. Nessa perspectiva, instrumentos vêm sendo criados com objetivo de modificar essa realidade. Entre esses instrumentos estão os indicadores, metodologias que ajudam a avaliar e a comunicar os processos presentes. O MESMIS, modelo de indicador voltado para avaliação de contextos rurais, tem sido compreendido como uma alternativa para ultrapassar a barreira meramente teórica e classificatória, apontando os diferentes pontos de um sistema de manejo. Nessa perspectiva, o método foi aplicado de forma transversal em seis unidades familiares, três de base tradicional e três de base alternativa, no assentamento Nova Aurora, em Pedras de Fogo (PB). De forma participativa foram selecionados nove indicadores de sustentabilidade compostos (Recursos Hídricos, Qualidade do Solo, Manejo, Diversidade, Trabalho e suas Relações, Participação, Autogestão, Situação Econômica, Mudança e Inovação), quantificados a partir de dados primários, coletados por meio de questionário e observações, que permitiram detalhar os agroecossistemas, determinar seus pontos críticos e observar que embora a cultura seja flexível a práticas agrícolas alternativas; técnicas de manejo tradicionais são usadas com frequência, em decorrência, principalmente, da frágil participação dos agricultores, e do baixo nível de conhecimento agroecológico. Ainda assim, o grupo dos agroecossistemas baseado na produção alternativa da cultura, apresentou melhores característica, do ponto de vista da sustentabilidade, nas dimensões social, econômica e ambiental, se comparada ao grupo dos agroecossistemas baseado na produção convencional.

Este trabalho objetivou pesquisar a relação da temperatura de superfície (LST) e do estoque de carbono no solo (ECS) com os diferentes tipos de uso e cobertura do solo (UCT). Sabe-se que tais parâmetros podem ser influenciados pelas atividades antrópicas, podendo afetar a integridade do agroecossistema (IAG) da bacia do Rio Corumbataí (BRC). Entende-se por IAG, a capacidade de manutenção de suas propriedades \"primitivas\" e prestação de serviços ecossistêmicos à sociedade. Para alcançar o objetivo proposto, a dinâmica de UCT foi mapeada, a partir da classificação de imagens do satélite Landsat e fotografias aéreas, dos anos de 1962 a 2011. A LST foi obtida por técnicas de sensoriamento remoto, utilizando a banda termal do sensor TM (Thematic Mapper) do Landsat, para os anos de 1985, 1990, 1995, 1999, 2002 e 2011. A análise do ECS foi feita a partir da coleta de amostras de solo, em diferentes UCT: mata nativa, cana-de-açúcar, pastagem e fruticultura, na profundidade de 0-10 e 10-20 cm. Os resultados indicaram que a LST e os ECS da área de estudo são influenciados pelo UCT e pelo manejo das culturas. Verificou-se ainda que algumas políticas agrícolas, adotadas no período de 1962 a 2011, influenciaram a dinâmica de UCT e, consequentemente, a capacidade do agroecossistema da BRC no fornecimento de serviços ecossistêmicos e também geraram custos ambientais. A abordagem interdisciplinar adotada neste trabalho, com o emprego das geotecnologias, mostrou ser capaz de avaliar a integridade do agroecossistema da BRC, podendo subsidiar o planejamento de uso do solo visando a maximizar a relação benefício/custo das atividades antrópicas, considerando a LST e o ECS. Tal abordagem pode ser aplicada em diferentes áreas do conhecimento para a análise da sustentabilidade e integridade ambiental dos agroecossistemas. / In this work, the aim was search the relationship between both surface temperature (LST) and soil organic carbon (SOC) with several sort of land use cover (LUC). We know such a parameters can be influenced by anthropic activities, it can affects the Corumbataí River basin (CRB) agro ecosystem integrity (AGI). AGI means, the capacity of both maintenance of its \"primitive\" properties and supplies public ecosystem service. Reaching the proposed goal, the LUC dynamic was mapping through both Landsat-TM image classification and aerial photography from 1962 to 2011. The LST has been obtained by remote sensing technique through Lansat-TM thermal band to the years 1985, 1990, 1995, 1999, 2002 and 2011. The ECS analyze was carried out by soil sample collected in different type of LUC: forest native, sugar cane, pasture and orchard, in the 0-10 and 10-20 cm depths. The results have indicated both the BRC of the LST and SOC are influenced by both together LUC and crop tillage. Furthermore, some agricultural policy adopted during from 1962 to 2011 influenced the LUC dynamic, thus the CRB agro ecosystem capacity of supply agro ecosystem services as well as provided environmental cost. The interdisciplinary approach employed, with the use of geotechnologies, has shown to be able to assessment the CRB agro ecosystem integrity, it can supports the LUC planning in order to maximize the benefit/cost ratio anthropic activities, considering both the LST and ECS. Such an approach can be applied in several knowledge areas to evaluation of sustainability and agro ecosystem environmental integrity.

Conventional agriculture is one of the widely adopted agricultural practices globally with an aim to increase production. This practice effectually increases yields, but with a growing array of environment and health concerns. Organic agriculture is reflected as a "sustainable substitute" for conventional agriculture, this phenomenon was investigated in this study by comparing the patterns of diversity and community structure of soil macrofauna as well as their relations with soil properties in organic and conventional ecosystems. Macrofauna was selected as model organisms for this study because these fauna groups are sensitive to changes in their environment and changes in their community structure offer an integrative assessment of ecosystem effects. Soil macrofauna were sampled using standardised procedures of Tropical Soil Biology and Fertility, in organic, intercropped and conventional wheat agroecosystems. The results show that the studied soil macrofauna groups, with an exception of Hymenoptera termites, are negatively affected by the intensity of conventional management, the organic and the intercropped systems exhibited similarities in species distributions, this was attributed to the cultural management practices applied to these systems where livestock manures and mulches, as well as practices such as no-till, are incorporated into the soil. Results obtained from the soil characterisation and analysis revealed that the dissimilarities in agroecosystem management have a significant influence on soil physicochemical properties, which consequently influences the distribution of the macrofauna assemblages. Stable isotopes did not reveal any significant differences between the systems, however macrofauna taxa, plant and soil samples from the organic systems were rich in natural abundance stable isotopes signatures, this aspect needs further investigation through extensive sampling under long term experiments, to observe clear differences. The general results of this study show that organic farming as an agricultural management strategy is the most stable system that positively supports the diversity in the soil macrofauna community and soil physicochemical properties as compared to the conventional system. Macrofauna diversity and functioning in the soil are affected by conventional agriculture, this may have negative implications for nutrient cycling and soil health in ecosystems cultivated under conventional monoculture, tillage and chemical intensifications. Continual research would be imperative to discover how the soil macrofauna contributes to ecosystem function and how they affect the soil ecosystem itself. / College of Agriculture and Environmental Sciences

Interactions are important drivers of selection and community structure, which makes the study of multi-species interactions critical for understanding the ecology and evolution of organisms. This dissertation includes four data chapters that examine the biotic and abiotic mechanisms that shape multi-species interactions in both tropical and temperate ecosystems. The first three data chapters (Chapters 2–4) were completed within a Neotropical rainforest in Costa Rica and focus on one plant genus, Piper (Piperaceae). The final data chapter (Chapter 5) was conducted within a working landscape of soybean (Glycine max) fields in eastern Maryland, USA. In Chapter 2, I explore intra- and inter-specific dietary niche partitioning of Piper fruits among three frugivorous bats, illustrating the importance of fine-scale mechanisms that facilitate species coexistence and influence plant–animal interactions. In Chapter 3, I demonstrate how the chemical ecology of a Neotropical shrub, Piper sancti-felicis, shapes fruit interactions with antagonists (fruit fungi) and mutualists (frugivorous bats and birds), developing a foundation for understanding evolutionary ecology of plant chemical traits based on phytochemical investment patterns. In Chapter 4, I describe the direct and indirect impacts of elevated temperature and CO2 concentration on the plant traits and interactions in Piper generalense, improving our understanding of the effects of climate change on a Neotropical plant–herbivore system. In Chapter 5, I explore the biotic (herbivore-induced plant volatiles) and abiotic (fine-scale weather conditions) drivers affecting insectivorous bat foraging in soybean fields in eastern Maryland, providing a pathway to further investigate new strategies for integrated pest management. As a collective work, this dissertation disentangles the nuances of multi-species interactions, exploring foundational mechanisms underlying biodiversity maintenance as well as answering applied questions to address a changing climate and aid sustainable agriculture. / Doctor of Philosophy / Everything in nature is connected, so studying ecological interactions requires us to view them from many different angles. As with most relationships, ecological interactions are multi-faceted and context-dependent. In this dissertation, I describe both tropical and temperate systems, collecting a variety of measurements from plants, microbes, and animals to explore the complicated relationships that exist between them. In Chapter 2, I explore how three species of fruit-eating bats may divide the use of a shared food resource (tropical pepper fruits in the genus Piper) to maintain separate populations and how those foraging differences may affect Piper plant populations. In Chapter 3, I characterize a chemical compound found in the fruits of a Piper plant species and test the effect of that compound on fruit fungi and fruit-eating bats and birds, leading to a better understanding of the selective pressures affecting fruit chemistry. In Chapter 4, I describe the direct and indirect effects of climate change on a Piper plant in the first study to measure the responses of tropical understory plants to treatments that mimic climate change using active warming and CO2 supplementation. In Chapter 5, I explore the fine-scale drivers of bat activity in soybean fields, including how weather conditions and the specific compounds emitted by insect-damaged plants may affect bat activity. As a collective work, this dissertation describes the complex relationships among plants and their many interactors, exploring questions from biodiversity maintenance to integrated pest management strategies.