Soil quality: a new index based on microbiological and biochemical parameters

Abstract.

The objective of this investigation was to evaluate some chemical, physical, biological and biochemical parameters and to determine a minimum data set to establish a soil quality index. Four different forms of management (native forest soil, soil deforested in 1982 and 1983 and under natural pasture for the last 8–10 years, soil deforested 26 years ago and under no-tillage for 6 years, and soil deforested 40 years ago and under conventional tillage) were established in an experimental site located in Entre Rios Province, Argentina in a Vertic Argiudoll soil. Soils sampled from the different treatments were monitored for their organic C, total N and extractable P contents and for aggregate stability, respiration C, dehydrogenase, urease, protease, acid phosphomonoesterase, β-glucosidase and arysulphatase activities. Different contents of organic C and total N between cultivated treatments and the forest soil indicated the extractive effect of cultivation and agricultural practices during different periods of time. Organic C presented significant correlations with most of the others properties. Among the various polynomial expressions that could be formulated, one (organic C=–0.4008 arylsulphatase+0.4153 dehydrogenase+0.4033 acid phosphomonoesterase+0.4916 β-glucosidase) had a R ² value which did not differ from that of the complete model.