The present proposal aims to assess how human disturbance and changes in rainfall regime affect the Caatinga ecosystem’s biota at different levels of biological organization (i.e, from populations to ecosystem level), by correlating these aspects with the theoretical reference shown in macro trends already documented in the tropics. The project will be developed in Catimbau National Park, a polygon of approximately 63,000 ha, and one of the most important protected areas in the Caatinga. The Park presents vocation for ecological studies of long-term and thus to become an LTER site due to a series of reasons: (1) it has a biological, archaeological and landscape heritage of inestimable value, (2) it shelters areas with different historical land use and anthropic disturbance on the vegetation of Caatinga, (3) there are already in place several research initiatives and training of human resources, and (4) in term of unit management aspects, logistics and infrastructure are favorable for long-term initiatives. Furthermore, the implementation and achievement of this project’s objectives are centered on: (1) establishment of a set of 30 permanent plots, (2) periodic multi-taxa inventories, (3) continuous monitoring of environmental and anthropogenic variables (4) consolidation of biological, land usage and environmental data on the basis of GIS type and (5) dissemination / transfer of information through a wide range of instruments.This proposal will be implemented by a network composed of 23 researchers supported by a number of undergraduate / graduate students, all from six national institutions and three other overseas. The main core of the graduate programs are Plant Biology, Biology Animal and Fungal Biology, all at the Federal University of Pernambuco (UFPE). In summary, the "LTER Catimbau National Park" is an important proposal and has the ability to expand knowledge about how dry biota respond to land use changes and precipitation, with all the implications that these answers may have for the management of biodiversity and the achievement of sustainable development in semi-arid regions.