Submitted by Franciele Moreira (francielemoreyra@gmail.com) on 2017-11-30T12:41:43Z No. of bitstreams: 2 Dissertação - Dryela Ribeiro Leite - 2017.pdf: 1923476 bytes, checksum: 119a7b686f9594584f016a595e9bae6b (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2017-11-30T13:00:22Z (GMT) No. of bitstreams: 2 Dissertação - Dryela Ribeiro Leite - 2017.pdf: 1923476 bytes, checksum: 119a7b686f9594584f016a595e9bae6b (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2017-11-30T13:00:22Z (GMT). No. of bitstreams: 2 Dissertação - Dryela Ribeiro Leite - 2017.pdf: 1923476 bytes, checksum: 119a7b686f9594584f016a595e9bae6b (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2017-09-11 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / The sustainability of the productive capacity of a soil is due to the type of land use and management system, which makes it necessary to adopt practices and technologies that aim at the continuity of the exploitation of its resources in a rational and long term way. The objective of this work was to evaluate the soil attributes of a Neossolo Quartzarênico and its ability to sequester carbon under biodiverse systems for two consecutive years. Chemical, physical and biological attributes and carbon sequestration capacity of six different soil use systems were evaluated: four Agroforestry Systems, a consolidated no - tillage system and a native forest area in good conservation status. Soil samples were collected at depths of 0-5 cm, 5-15 cm, 15-30 cm and 30-50 cm for the chemical, physical and carbon analyzes in the soil and at depth of 0-10 cm for the microbiological analyzes. Data were submitted to analysis of variance and the Scott-Knott 5% mean test, and as a complementary analysis we used the multivariate canonical analysis technique and the Tocher grouping method. The SAF4 system was the system that presented the most promising as the characteristics evaluated. The management of this system favored soil fertility even though it was extremely sandy and did not compromise soil structure, provided greater efficiency of microbial biomass, increased nutrient cycling, organic matter production, humification and carbon storage capacity. the system that presented the best results for the physical characteristics of the soil evaluated. / A sustentabilidade da capacidade produtiva de um solo é decorrente do tipo de sistema de uso e manejo da terra, o que torna necessário a adoção de práticas e tecnologias que visem a continuidade da exploração de seus recursos de maneira racional e a longo prazo. Este trabalho objetivou avaliar os atributos do solo de um Neossolo quartzarênico e sua capacidade de sequestrar carbono sob sistemas biodiversos por dois anos consecutivos. Foram avaliados atributos químicos, físicos, biológicos e a capacidade de sequestro de carbono de seis diferentes sistemas de uso do solo: quatro Sistemas Agroflorestais, um sistema de plantio direto consolidado e uma área de floresta nativa em bom estado de conservação. As amostras de solo foram coletadas nas profundidades de 0-5 cm, 5-15 cm, 15-30 cm e 30-50cm para as análises química, física e carbono no solo e na profundidade de 0-10cm para as análises microbiológicas. Os dados foram submetidos à análise de variância e ao teste de média Scott-Knott a 5%, e como análise complementar foi utilizada a técnica multivariada de análise canônica e o método de agrupamento de Tocher. O SAF4 foi o sistema que se apresentou mais promissor quanto as características avaliadas. O manejo desse sistema favoreceu a fertilidade do solo mesmo esse sendo extremamente arenoso e não comprometeu a estrutura do solo, proporcionou uma maior eficiência da biomassa microbiana, maior ciclagem de nutrientes, produção de matéria orgânica, humificação e capacidade de estocagem de carbono, sendo ainda o sistema que apresentou os melhores resultados para as características físicas do solo avaliadas.

<p>Here, we seek to address the importance of biodiversity in plant ecosystems. We examined the productivity-diversity relationship through the lens of the modern coexistence theory, using a combination of both experimentation and mathematical simulation. We did this by tracking and comparing the productivity of mixed and monoculture plots, analyzing the growth responses of individual trees at forest plots (Chapter 1), confirming the productivity-diversity relationship in a greenhouse experiment using local herbaceous plants (Chapter 2), and finally simulating the productivity response of monoculture vs polyculture plantations to specialist enemy attack (Chapter 3).</p><p>It is no surprise that biodiversity has been decreasing at an exponential rate on the global scale because of effects such as habitat fragmentation, invasive species, spreading pathogens, and anthropogenic influences. Ecologists often found that plants in more species rich locations often exhibited higher productivity and stability in the face of stress. One such phenomenon is known as the productivity diversity relationship that implies biodiversity is key to sustaining ecosystems. Notably, while efforts are being put forth to address ecosystem destruction, much of the current tree planting strategy in the USA is based on timber profit rather than forest productivity and species coexistence with tree biology often being a secondary consideration. These thought processes are in opposition with historical experiments that indicate polyculture communities create more biomass making them significantly more productive than monocultures. However, we also acknowledge that it is not simply biodiversity that must be taken into consideration for a productive ecosystem but also species interaction through coexistence indicate whether or not a community will persevere. These interactions can be addressed using the modern coexistence theory which depends on these complementarity and fitness similarities for species to coexist through time. Here, we seek to address the importance of biodiversity in plant ecosystems. We examined the productivity-diversity relationship through the lens of the modern coexistence theory, using a combination of both experimentation and mathematical simulation. We did this by tracking and comparing the productivity of mixed and monoculture plots, analyzing the growth responses of individual trees at forest plots (Chapter 1), confirming the productivity-diversity relationship in a greenhouse experiment using local herbaceous plants (Chapter 2), and finally simulating the productivity response of monoculture vs polyculture plantations to specialist enemy attack (Chapter 3). Our research across the combination of approaches used found that species with overlapping niches and very different finesses will exclude one another due to high competition. Further, the productivity diversity correlation is necessary for ecosystem growth, but it is not sufficient for species coexistence. However, species can maintain this positive relationship despite a lack of coexistence if they maintain niche complementarity. Lastly, using a theoretic game model we were able to identify the impacts of a specialist pest on polyculture and monoculture forest. These results showed that a polyculture forest was more productive than that of a monoculture forest regardless of the presence of a specialist enemy. The results of the multiple threads of evidence found from these combined experiments indicate that while the productivity diversity correlation is important to ecosystems it is likely due to the impacts of niche complementarity that determine whether or not species will be productive within an ecosystem.</p>