Colêmbolos (arthropoda: hexapoda: collembola) numa área de caatinga do nordeste brasileiro

Edaphic ecosystems are the basis for the production of terrestrial biological resources and their dynamics affect not only the natural environment but also society and their economic activities. In Caatinga biome, the semi-arid climate associated with an inadequate soil management has increased the degradation and loss of productive potential of the soil. In this context, the study of soil fauna, including springtails, becomes an important indicator of soil quality. This study aimed to evaluate the fauna of Collembola in an area of Caatinga of Rio Grande do Norte State and the influence of biotic and abiotic factors, such as soil, vegetation and climate characteristics, on the structure of the taxocenosis. The environmental variables which were used were the following ones: granulometry (represented by the proportion of sand), quantity of organic matter and soil pH, richness, density and aerial biomass of the vegetal structure, and necromass. We used pitfall traps intending to collect specimens of the epiedaphic fauna of Collembola in 30 points located on Cauaçu Farm, João Câmara, RN, in July (rainy season) and November (dry season) 2011. We collected 5513 individuals of 15 species distributed in 13 genera and 9 families of Collembola. Five of the recorded species are new to science, confirming the expected high degree of endemism for Caatinga biome, and the highest abundance was recorded in the rainy season, which suggests Collembola sensitivity to low humidity. Four species were more abundant in the dry season, all of them belonged to the Order Entomobryomorpha. Results of statistical analyzes suggest that plant species richness, aerial biomass of vegetal structure, proportion of sand in the soil, pH and humidity are the main influences to the abundance of Collembola in the region studied

Caracterização e composição florística de uma comunidade savânica no Rio Grande do Norte, Brasil : subsídios para a conservação

Studies on Brazilian biodiversity are still very few and can observe the difference of knowledge between the different regions of the country. This affirmation can be verified in the investigation to identify the rare species in Brazil and the key biodiversity areas (ACBs). In that study were identified for Brasil 2.256 rare species and 752 ACBs. The Rio Grande do Norte (RN) was the only Brazilian state that has not been identified any rare species and no ACBs, possibly due to the lack of floristic studies in this state. A particular area was selected for this study: an area of ecological tension with savanna physiognomy in Rio do Fogo, RN. This savanna community is represented in RN in a fragment and immersed in restinga and caatinga and was identified and described only through of radar imagens there are no studies to date in loco . We have prepared the following questions about this community savanna: 1) The region delimited and described by through of radar images by the RADAMBRASIL, 1976, can be associated of the Cerrado, in terms of floristic ?; 2) What is the floristic composition of this area? This area includes rare species, endemic or endangered? 3) What is the geographical and phytogeographical distribution of plant species registered in this area? 4) Those plant species registered are endemic or have affinity with other areas phytoecological Brazilian? To answer these questions we performed a floristic inventory of the August 2007 to September/2009. The results are presented in two chapters (manuscripts). The first chapter, titled "The Savannah Rio Grande do Norte: floristic links with other plant formations in the Northeast and Center-West Brazil" was submitted to the Revista Brasileira de Botância. Chapter 1 discusses the phytogeographical distribution of the species, by comparing floristic studies conducted in the Cerrado, Caatinga and Restinga in the Northeast and Cerrado of the Central Brazil. The analysis of data of this study and compilation with other studies indicated that: i) the record of 94 plant species; ii) of total species, about 64% are associated with the Cerrado, the second specialized bibliography, and about 78% as the List of Species of Flora of Brazil. However, about 73% of total species (94) are also distributed in the Caatinga, the Atlantic forest 64%, the Amazon forest 64%, the Pantanal 15% and the Pampa 12%. Floristically the data show that the community studied is influenced by other floras, has a structure where grasses dominate and also because of his appearance the same savanna then be classified as a Savana gramíneo-lenhosa do tabuleiro . Chapter 2, titled "Considerations on the flora of a savanna community in Rio Grande do Norte, northeastern Brazil: Subsidy key area for conservation" was submitted to the Revista Natureza e Conservação. This has the objective of improve the knowledge of flora of Rio Grande do Norte and to identify possible rare species and consequently increase the key areas of biodiversity in Brazil. The data indicated that: i) of 94 species registered in the study area, 40 were new records for the Rio Grande do Norte state; ii) These citations to unpublished state, Stylosanthes montevidensis Vogel (Fabaceae) and Aristida laevis (Nees) Kunth (Poaceae) are indicated for the first time to the Northeast of Brazil; iii) are registered in the area 24 species endemic to Brazil and 63 non-endemic; iv) Aspilia procumbens Baker (Asteraceae) registered in the area is considered a restricted species and micro endemic Rio Grande do Norte, ie rare species; v) Aspilia procumbens is also cited in the category of critically endangered species and Stilpnopappus cearensis Hubber (Asteraceae) a species vulnerable to extinction. This study shows a new area phytoecological in Rio Grande do Norte and indicates the area's potential to contribute with the sites of global significance for biodiversity conservation, either locally, regionally and nationally. This will certainly contribute to respond some targets set by the Global Strategy for Plant Conservation and the Convention on Biological Diversity such as the inventory of vegetal diversity in a region with little collection, which will provide data that contributes to questions and themes related to biodiversity.

O papel dos quintais urbanos na segurança alimentar, bem estar e conservação da biodiversidade

Residential homegardens have environmental and social roles in the urban environment. These green spaces can potentially minimize the impacts caused by the growth of cities, being an alternative to connect fragmented areas or offer refuge to wildlife and therefore support the conservation of biodiversity. In addition, the homegardens demonstrate a leading role in increasing human well-being by promoting socialization opportunities, contact with nature, local culture as well as improvements in food security for the urban families. Nevertheless, it is still unclear what specific characteristics of homegardens can act effectively in the conservation of the biodiversity, as well as in the construction of food security and well being of the homegardeners and their families. The first chapter of this thesis analyzed the diversity of plant species (native and exotic) and assessed the contribution of different types of urban gardens (ornamental and forest gardens alike) in the presence of wildlife such as birds, monkeys and lizards. In the second chapter we evaluated the contribution of those gardens to the welfare and food security of their owners. In order to do this, 41 gardens were visited in Pium, a southern coastal town in the northeastern Brazil, which also happens to be in a periurban region undergoing rapid urban expansion and pressure from the real estate market. We surveyed the planned biodiversity and fauna associated with homegardens. The data related to food security and welfare were sampled through interviews with the person in charge of taking care of the gardens. These interviews covered issues on the supply of food from the garden and absence of chemical products, as well as aspects of the GNH indicator (Gross National Happiness). The results showed that these homegardens generally contribute little to the maintenance of native plant species (native species = 29/ total = 187). From its main features, the gardens were classified as ornamental, forest gardens and forest farms. These groups had a different effect on the presence of the animals studied and the last two contained most of the sampled native species. The diversity of plants and trees was a good predictor of the presence of birds and monkeys. Thus, the contribution of yards for the conservation of biodiversity depends on the type of garden: some even can have negative effects on conservation. These results can direct new approaches to detailed understanding of gardens and also of public policies applied to urban planning. The results of the second chapter showed that the two types of forest gardens contributed to household food security, for providing food and medicinal herbs, which mostly did not have pesticides and chemical 12 fertilizers. But the three groups of gardens are important components for the well being of their stakeholders. Gardens help promote the transmission of knowledge on agriculture, socialization, contact with nature and bring up feelings related to peace and harmony. Thus, forest gardens can be considered important means to get through public projects and policies designed to encourage biodiversity and promote food security and well-being in urban areas