Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2016-05-10T23:18:28Z No. of bitstreams: 1 KionaraSarabellaTuribioESilva_DISSERT.pdf: 1524779 bytes, checksum: a034505b357fab3aef4e1f83a7bbc3d6 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2016-05-18T19:54:55Z (GMT) No. of bitstreams: 1 KionaraSarabellaTuribioESilva_DISSERT.pdf: 1524779 bytes, checksum: a034505b357fab3aef4e1f83a7bbc3d6 (MD5) / Made available in DSpace on 2016-05-18T19:54:55Z (GMT). No. of bitstreams: 1 KionaraSarabellaTuribioESilva_DISSERT.pdf: 1524779 bytes, checksum: a034505b357fab3aef4e1f83a7bbc3d6 (MD5) Previous issue date: 2015-06-15 / O bioma Caatinga, ecossistema de clima semi?rido localizado no nordeste do Brasil, apresenta forte sazonalidade com baixo regime de precipita??o. Esta regi?o possui as proje??es de mudan?as clim?ticas mais alarmantes do pa?s, com o aumento temperatura do ar e a redu??o da pluviosidade com tend?ncias mais fortes que as previs?es m?dias globais. As mudan?as clim?ticas no bioma podem acarretar na diminui??o da cobertura vegetal e altera??o de sua distribui??o, bem como do funcionamento ecossist?mico. Desta forma, influencia fortemente na diversidade de esp?cies. Nesse contexto, a proposta desse estudo ? modelar a din?mica da vegeta??o em fun??o das condi??es ambientais (pluviosidade e temperatura), bem como predizer as consequ?ncias das mudan?as clim?ticas, baseadas nesses determinantes ambientais para o verdor da vegeta??o. O ?ndice de vegeta??o EVI (Enhanced Vegetation Index) foi usado para estimar o verdor da vegeta??o no bioma. A fim de considerar a forte autocorrrela??o temporal e espacial, bem como a heterogeneidade presente nos dados, v?rios modelos GLS (Generalized Least Squares) foram desenvolvidos e comparados para se obter o melhor modelo. Tal modelo refletiu a influ?ncias das condi??es ambientais na previs?o do verdor da vegeta??o no futuro. Diante da aplica??o dos novos cen?rios de mudan?as clim?ticas no modelo, a modifica??o dos determinantes ambientais, pluviosidade e temperatura, influenciou negativamente no verdor da vegeta??o no bioma Caatinga. Esse modelo foi usado para criar imagens de vegeta??o potencial nos per?odos presente e futuro do bioma Caatinga considerando que at? 2040 haver? uma diminui??o de 20% da precipita??o e um aumento de 1?C na temperatura; at? 2070 haver? uma diminui??o de 35% na precipita??o e um aumento de 2,5?C na temperatura; e at? o final do s?culo o percentual de diminui??o das chuvas alcan?ar? 50% e a temperatura ter? um aumento de at? 4,5?C. Os resultados desse estudo sugerem que o funcionamento do ecossistema ser? afetado com a diminui??o de 5,9% do verdor da vegeta??o at? 2040, 14,2% at? 2070 e 24,3 % at? o final do s?culo. A vegeta??o da Caatinga em ?reas de baixa altitude (maior parte do bioma) ser? mais afetada pelas mudan?as clim?ticas. / The Caatinga biome, a semi-arid climate ecosystem found in northeast Brazil, presents low rainfall regime and strong seasonality. It has the most alarming climate change projections within the country, with air temperature rising and rainfall reduction with stronger trends than the global average predictions. Climate change can present detrimental results in this biome, reducing vegetation cover and changing its distribution, as well as altering all ecosystem functioning and finally influencing species diversity. In this context, the purpose of this study is to model the environmental conditions (rainfall and temperature) that influence the Caatinga biome productivity and to predict the consequences of environmental conditions in the vegetation dynamics under future climate change scenarios. Enhanced Vegetation Index (EVI) was used to estimate vegetation greenness (presence and density) in the area. Considering the strong spatial and temporal autocorrelation as well as the heterogeneity of the data, various GLS models were developed and compared to obtain the best model that would reflect rainfall and temperature influence on vegetation greenness. Applying new climate change scenarios in the model, environmental determinants modification, rainfall and temperature, negatively influenced vegetation greenness in the Caatinga biome. This model was used to create potential vegetation maps for current and future of Caatinga cover considering 20% decrease in precipitation and 1 ?C increase in temperature until 2040, 35% decrease in precipitation and 2.5 ?C increase in temperature in the period 2041-2070 and 50% decrease in precipitation and 4.5 ?C increase in temperature in the period 2071-2100. The results suggest that the ecosystem functioning will be affected on the future scenario of climate change with a decrease of 5.9% of the vegetation greenness until 2040, 14.2% until 2070 and 24.3% by the end of the century. The Caatinga vegetation in lower altitude areas (most of the biome) will be more affected by climatic changes.

Made available in DSpace on 2014-12-17T14:33:08Z (GMT). No. of bitstreams: 1 DanielO_DISSERT.pdf: 1269498 bytes, checksum: 758aaeb33fe30cc21606c68e15b68f35 (MD5) Previous issue date: 2013-08-31 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / The soil macrofauna is influenced to several biotic and abiotic environmental factors, from changes in the physical environment to a variety of interactions among the species involved, affecting the patterns of biodiversity of soil fauna. The power and specificity of the mechanisms that act on soil organisms vary greatly depending on environmental conditions at different scales of space and time. The Caatinga has great spatial heterogeneity of vegetation, climate and soil, so the soil macrofauna would follow this local spatial variation in the environment? This study aimed to investigate the effects of local environmental variables on biological parameters (taxa richness, total abundance and biomass) of soil macrofauna in a fragment of caatinga in Jo?o C?mara, Rio Grande Norte, Northeast Brazil. The study was conducted in the Caua?u farm, where a grid of 2000m x 500m was drawn, and later, 30 sampling points were randomly selected. The methodology used to collect the macrofauna was the TSBF method. We tested the effects of 10 environmental variables on macrofauna across the plots and across the layers of soil. The hypothesis that macrofauna soil responds to changes in the environment was not supported throughout the plots, but was confirmed to soil layers. The soil macrofauna shows a pattern of concentration in the surface layer and decreases considerably in the deeper layers. This pattern had significant and positive relationship with the aerial plant biomass and fine root stock. The aerial plant biomass releases plant necromass that accumulates in the surface layer, providing an important source of resource and shelter for soil macrofauna, explaining their greater abundance in this layer. The roots are used as a means for the arrival of nutrients to the soil from the primary production, thus a greater amount of root conditions higher food intake for macrofauna, especially the herbivores / A macrofauna de solo est? sujeita a diversos fatores ambientais bi?ticos e abi?ticos, desde varia??es no ambiente f?sico ? variedade de intera??es entre as esp?cies envolvidas, afetando os padr?es de biodiversidade da fauna de solo. A for?a e a especificidade dos mecanismos que atuam sobre os organismos de solo variam bastante de acordo com as condi??es ambientais em diferentes escalas de espa?o e de tempo. A Ccaatinga apresenta grande heterogeneidade espacial da vegeta??o, clima e solo, sendo assim, a macrofauna de solo acompanharia essa varia??o espacial local no ambiente? Este estudo teve como objetivo investigar os efeitos das vari?veis ambientais locais sobre os par?metros biol?gicos (riqueza de t?xons, abund?ncia de indiv?duos e biomassa) da macrofauna de solo em um fragmento de Caatinga no munic?pio de Jo?o C?mara, Rio Grande no Norte, Nordeste do Brasil. O estudo foi conduzido na fazenda Caua?u, onde foi tra?ada uma grade de 2000m x 500m, e posteriormente, foram sorteados 30 pontos de coleta. A metodologia usada para a coleta da macrofauna foi o m?todo TSBF. Foram testados os efeitos de 10 vari?veis ambientais sobre a macrofauna ao longo das parcelas e ao longo das camadas de solo. A hip?tese de que a macrofauna de solo responde as varia??es no ambiente n?o foi corroborada ao longo das parcelas, mas foi confirmada para as camadas de solo. A macrofauna de solo apresenta um padr?o de concentra??o na camada superficial e diminui consideravelmente nas camadas mais profundas. Padr?o esse que teve rela??o significativa e positiva com a biomassa vegetal a?rea e o estoque de ra?zes finas. A biomassa vegetal a?rea libera necromassa vegetal que se acumula na camada de superf?cie, constituindo uma importante fonte de recurso e de abrigo para a macrofauna de solo, explicando sua maior abund?ncia nessa camada. As ra?zes servem como via para a chegada ao solo de nutrientes provenientes da produ??o vegetal, dessa forma, uma maior quantidade de ra?zes condiciona maior entrada de alimento para a macrofauna, principalmente os herb?voros