Estrutura da assembleia de besouros scarabaeinae (coleoptera: scarabaeidae) em floresta ripária com diferentes situações de conservação na bacia hidrográfica do R io dos Sinos, no Sul do Brasil

Abstract

The human economy, health and well being are intimately connected with the functionality of the ecosystem. As the interface between terrestrial and aquatic ecosystems, riparian habitats are an important component in the landscape for many species. Studies on the patterns of insect communities in tropical rainforests are extremely necessary to identify the consequences of habitat fragmentation on the biota, and assist conservation plans. Scarabaeinae represents a group of insects globally distributed, however both its biology as well as ecology are unknown for most species. The dung beetles are important decomposer organisms, involved in many ecosystem functions. Moreover, these insects are very sensitive to habitat destruction, showing patterns of organization distinguished between degraded when compared to continuous forest. This study had as aim: 1) perform an inventory of the diversity of the Scarabaeinae fauna and their functional guilds in riparian forest ecosystem; 2) analyze the temporal dynamics of dung beetles community by along an annual cycle in riparian forests; and 3) evaluate the influence of different conditions of conservation of riparian vegetation in the richness, abundance and composition of Scarabaeinae in a hydrographic basin in Southern Brazil. This study was performed in riparian forests of second-order streams with different conditions on the upper portion of hydrographic basin of the Rio dos Sinos, in Southern Brazil. Pitfall traps baited with human feces and rotting pork were placed in four samplings during an annual cycle (2010-2011) at four places in each of three streams. A total of 1289 beetles were collected, distributed in 29 species of 11 genera. The species classified as paracopríds and telecopríds predominated in the community. The beetle richness and composition varied among sites with different situations of conservation of riparian vegetation throughout the period, and the richness was highest in spring and summer, as well as in the most conserved riparian vegetation. The dung beetles seem to indicate great environmental variability, and therefore know the species characteristics of each type of environment, as well as gain an understanding of the relationships between ecological functions and ecosystem services that run is of vital importance for future management of ecosystems. Together with other groups of invertebrates, these beetles can provide a broader taxonomic representation in the development of practices and conservation policies. Thus, this study provides information both about the scope of the validity of knowledge about dung beetles to the subtropics, as well as in obtaining knowledge for the Neotropical region.