Annual and infra-annual variations in subterranean ecosystems: implications for environmental studies and cave preservation

Abstract

Results from medium to long term studies and extended observations demonstrate the occurrence of annual (seasonal) and infra-annual variations in Brazilian cave ecosystems. Bats and invertebrate communities from different karst areas are focused, with emphasis on the Alto Ribeira (SE Brazil). For a biologically meaningful description of the subterranean biodiversity and to understand the functioning of these unique ecosystems, sampling efforts compatible with their dynamics are required, especially when the purpose is to classify caves into relevance degrees, making their destruction possible. The inadequacy of the current environmental policy is discussed, based on conceptual and methodological flaws of the recent Decree 6640/2008, regulated by the IN MMA 2/2009. In view of the ineffectiveness of these legal articles, I propose their complete revision.