2 resultados para distribuição espaço-temporal

em Repositorio Institucional da UFLA (RIUFLA)


Relevância:

90.00% 90.00%

Publicador:

Resumo:

Nature Protection Areas (NPA) are important in the modern world, although still created with no well-defined criteria, overall in state and municipal spheres. In addition, there are no consistent information on the existence or factors that influence the creation and distribution of these areas. The present work had the objectives of identifying the Nature Protection Areas in Minas Gerais, Brazil, considering the municipalities and their mesoregions; perform a space-temporal analysis of the NPAs in Minas Gerais; relate the existence of NPAs with the Municipal Human Development Index (MHDI) and the municipal Gini Index (GI); relate the existence of NPA with the space-temporal and population density of each municipality; relate the Gross Domestic Product (GDP) with the presence of NPAs; relate the existence of NPAs with the occurrence of preservation areas in municipalities within the Atlantic Forest Biome; and verify the influence of the Ecological Sales and Services Tax (Ecological ICMS) institute over the creation of municipal NPAs in Minas Gerais. To reach these objectives, we researched databases, governmental websites, contacted managers and sent questionnaires to the 853 municipalities of Minas Gerais. After tabulating the data, statistical tests were applied to verify possible correlations. The results showed that the state has 9.26% of its territory protected, with the predominance of units of Sustainable Use, especially Environmental Protection Areas, which constitute 69.9% of this area. Only 1.96% of the territory are protected by Integral Protection (IP). We found no correlation between MHDI and the presence of NPAs. However, we verified that municipalities with IP units present higher GI when compared to the others, suggesting that the presence of this conservation unit (CU) model may be associated to social inequality. The results also showed a higher concentration CU in regions that use little of its natural resources as main economic basis and in municipalities with higher GDP. We also registered a positive correlation between the size of the municipalities, of the mesoregions, preserved area of the Atlantic Forest and population density. The Ecological ICMS did not contribute for a better IP in the state and, currently, does not represent an incentive to the creation of CU in Minas Gerais, even in the case of Environmental Protection Areas. This work registered a high degree of vulnerability if the protection system in this state, based on low restriction conservation units.

Relevância:

80.00% 80.00%

Publicador:

Resumo:

Food webs have been used in order to understand the trophic relationship among organisms within an ecosystem, however the extension by which sampling efficiency could affect food web responses remain poorly understood. Still, there is a lack of long-term sampling data for many insect groups, mainly related to the interactions between herbivores and their host plants. In the first chapter, I describe a source food web based on the Senegalia tenuifolia plant by identifying the associated insect species and the interactions among them and with this host plant. Furthermore, I check for the data robustness from each trophic level and propose a cost-efficiently methodology. The results from this chapter show that the collected dataset and the methodology presented are a good tool for sample most insect richness of a source food web. In total the food web comprises 27 species belonging to four trophic levels. In the second chapter, I demonstrate the temporal variation in the species richness and abundance from each trophic level, as well as the relationship among distinct trophic levels. Moreover, I investigate the diversity patterns of the second and third trophic level by assessing the contribution of alfa and beta-diversity components along the years. This chapter shows that in our system the parasitoid abundance is regulated by the herbivore abundances. Besides, the species richness and abundances of the trophic levels vary temporally. It also shows that alfa-diversity was the diversity component that most contribute to the herbivore species diversity (2nd trophic level), while the contribution of alfa- and beta-diversity changed along the years for parasitoid diversity (3rd level). Overall, this dissertation describes a source food web and bring insights into some food web challenges related to the sampling effort to gather enough species from all trophic levels. It also discuss the relation among communities associated with distinct trophic levels and their temporal variation and diversity patterns. Finally, this dissertation contributes for the world food web database and in understanding the interactions among its trophic levels and each trophic level pattern along time and space