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Microbial activity and biochemical properties are important indicators of the impact of organic composting on soil. The objective of this study was to evaluate some indicators of soil microbial and biochemical processes after application of compost (household waste). A Typic Acrustox, sampled at a depth of 10 cm under Cerrado biome vegetation, was evaluated in three treatments: control (soil without organic compost amendment) and soil with two doses of domestic organic compost (10 and 20 g kg -1 soil). The following properties were evaluated: released C (C-CO 2 ): microbial respiration 15 days after incubation; microbial biomass C (MBC); total glucose (TG); metabolic quotient (qCO 2 ); and enzyme activity of β− β− β− β− β−glucosidase and acid and alkaline phosphatase. The application of household compost, at doses of 10 and 20 g kg -1 Typic Acrustox, resulted in significant gains in microbial activity, organic C and C stock, as evidenced by increased MBC and TG levels. On the other hand, qCO 2 decreases indicated greater microbial diversity and more efficient energy use. The addition of compost, particularly the 20 g kg -1 dose, strongly influenced the enzyme β− β− β− β− β−glucosidase and phosphatase (acid and alkaline). The β− β− β− β− β−glucosidase activity was significantly increased and acid phosphatase activity increased more than the alkaline. The ratio of β− β− β− β− β−glucosidase to MBC was greater in the control than in the composted treatments which suggests that there were more enzymes in the control than in the substrate or that the addition of compost induced a great MBC increase.Index terms: Cerrado, Soil respiration, microbial biomass, glucose, phosphatase, β− β− β− β− β−glucosidase.(

Microbial and biochemical properties are of great importance in soil quality evaluation. In Brazil, and especially in the cerrado (Brazilian savanna), benchmarking studies are needed to assess the impacts of land use on microbial and biochemical indicators. This study aimed to compare the impacts of land use on the microbial, chemical, and biochemical properties of the soil under Cerrado (CE), 32‐yr‐old pine forest (PF) and 11‐yr‐old no‐till (NT). Soil samples were collected at a depth of 0 to 10 cm in January, June, and December of 2008 and were evaluated based on chemical properties, basal respiration, soil organic carbon (SOC), microbial biomass carbon (MBC) and enzymes (β‐glucosidase, dehydrogenase and acid, neutral, and alkaline phosphatases). Comparative analysis of respiratory activity and MBC showed that the NT system had a positive effect and PF a negative one relative to the reference CE. NT soil management practices improve quality mainly by benefiting chemical characteristics (C and N), increasing MBC, and increasing microbial activity relative to CE and PF. Soil enzymatic activity (dehydrogenase, β‐glucosidase and phosphatase) was lower in PF and higher in NT than in CE. Principal component analysis showed that indicator variability, regarding soil sampling period, was higher in NT than in either PF or CE. In conclusion, we recommend β‐glucosidase and MBC as indicators of the impacts of land use practices.

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