Distribuição dos organismos edáficos e evolução de CO2 em áreas de caatinga sob diferentes estágios sucessionais na Paraíba.

Abstract

This work aims to evaluate the effects o f different soil management systems on the modifications on the abundance o f the groups o f soil mesofauna and macrofauna and to determine the microbial activity through C 0 2 liberation. The experiment was carried out at Cachoeira de São Porfirio Farm, situated in the municipality o f Varzea-PB, between the months o f September and December, 2009 (dry season) and March to June, 2010 (rainy season). It was used areas in successional stages (without vegetation caatinga, initial, secondary and caatinga climax stages). Soil samples were collected in order to extract the organisms groups o f mesofauna using the Berlese-Tullgren modified method and in order to evaluate macrofauna it was used pitfall Tretzel modified and to evaluate the microbial activity it was used the method established by Grisi. In the macrofauna composition during the different studied seasons, the main groups found were: Hymenoptera, Coleoptera e Aranea whereas in the mesofauna composition the group was acarina, the climax area shown a greater density o f individuais. Microbial activity was larger at night when compared to the day time, as it was helped by the humidity and soil temperature; there has been significant difference on the C 0 2 liberation during the studied periods.