Organismos edáficos como bioindicadores da recuperação de solos degradados por arenização no Bioma Pampa

Abstract

Edaphic organisms are sensible to environment alterations and have been used as indicators of soil quality changes. These modifications can be promoted by degradation or agradation events. The study area is located in Alegrete, Rio Grande do Sul. It was analyzed the role of epigeic soil fauna as bioindicator of soil degradation by arenização and its restoration by revegetation with Lupinus albescens Hook. & Arn., a native fabaceous of Bioma Pampa. The treatments were constituted of soil under natural covering with Lupinus albescens, degraded area recovered with Lupinus albescens by one year (T1), degraded area recovered with Lupinus albescens by three years (T3), degraded area (SA) and native grass field (CN). The sampling was made in February and May of 2006 with PROVID traps. It was determined the abundance of organisms at Order level, the organisms richness, the diversity and evenness Shannon' index. The process of Arenização reduced the development of sampled edaphic populations, while revegetation showed positive effects in the recolonization of the area. Colembolla group was a good bioindicator of degradation and restoration effects. The Shannon diversity index was not satisfactory to evaluate the edaphic fauna if disconnected of other parameters.