BIOQUALIDADE DE ÁREA DEGRADADA PELA EXTRAÇÃO DE ARGILA, REVEGETADA COM Eucalyptus spp. E SABIÁ

Abstract

An experiment was carried out to evaluate the biological and chemical soil quality of a degraded area of clay extraction, after it has been re-vegetate with Eucalyptus spp. and Mimosa caesalpiniifolia, cultivated in single or inter-cropping systems. It was used as soil biological quality indicators the total microbial activity, evaluated by enzymatic method of the hydrolize of the fluoresceína diacetato (FDA) and soil total respiration; and, the diversity of arbuscular mycorrhizal fungi (AMF). To evaluate the chemical quality it was used some chemical characteristics of the soil. The random blocks experimental design was used, with nine treatments + control. The treatments were constituted of single plantings of Mimosa caesalpiniifolia (sabiá) and of four species of eucalyptus (Eucalyptus camaldulensis, Eucalyptus pellita, Eucalyptus tereticornis, Eucalyptus robusta) and intercropping plantings of sábia with the four eucalyptus species, with four repetitions. The control treatment (degraded soil without any re-vegetation) was an area inside of the digging of clay extraction, with four replicates. The experimental unit was composed by 36 plants. After 36 months, the soils with single plantings of E. pellita and sabiá presented, in relation to the control treatment (without vegetation), larger microbial activity, evaluated by both the method of FDA and by total respiration, larger diversity of AMF and larger concentrations of nitrogen. The microbial soil activity, as much for the method of FDA as for the breathing, it was larger in intercropping plantings of E. pellita with sabiá, when compared with the control treatment. The AMF Glomus and Acaulospora were largest genus found in all treatments, however, in the control treatment it was found only the AMF species Glomus macrocarpum.