MICROBIOLOGIC AND BIOCHEMICAL ATTRIBUTES AS INDICATORS OF THE RECOVERY OF DEGRADED AREAS, IN ITAJUBÁ/MG

Abstract

This paper evaluated and compared the microbial and biochemical parameters of degraded areas, in rehabilitation, with natural areas, considered reference, without recent human interference, in Itajubá (MG, Brazil), to verify their capacity to indicate the soil quality and rehabilitation capacity. Soil samples were collected in February 2003 (summer), on six sites: three in natural areas and other three in degraded areas, under rehabilitation. Total density of fungi and bacteria, phosphate solubilizing microorganisms, microbial biomass C and activity were evaluated. Moreover were established relationships among visual and microbial and biochemical parameters, verifying their potential use as indicators in studies of soil rehabilitation on degraded areas. Degradation promoted strong negative impact in the soil microbiota, reducing the number of all microbial groups studied, microbial activity and biomass. The soil microbial and biochemical parameters were considered good indicators of the soil rehabilitation on degraded areas. The soil rehabilitation evidenced by visual parameters of soil, plants and organisms had not direct positive relationship with those observed in the underground through microbial and biochemical indicators. These findings show that rehabilitation of degraded areas is strongly affected by soil microbial and biochemical parameters.