Some enzyme activities of two Histosols and their relationship with soil biological and chemical properties

Soil enzyme activities are considered as one of the most important biological indicators and reflect the soil quality and fertility. Current study was conducted to investigate the relationship between Urease, Invertase, Alkaline phosphatase and Aryl sulphatase activities of two Histosols (located in Kerman and Shahrekord provence) and some of the soil chemical and biological properties. Soil samples were collected from 3 soil profiles (0-120 cm, at each 20 cm layer). The enzyme activities were determined as described in standard methods. Results of Pearson correlation coefficients showed that organic carbon (r > 0.86**), total nitrogen (r > 0.88**), phosphorus (r > 0.77**), carbohydrates (r > 0.86**), microbial respiration (r > 0.94**) and microbial biomass carbon (r > 0.87**) had a positive and significant effect (p< 0.01) on the enzymatic activities of two studied soils. In addition, stepwise regression model was used to evaluate the relative importance of soil properties in conjunction with enzyme activities. The results showed that microbial biomass carbon and phosphorus had negative effects on the activity of some enzymes, while organic carbon, total nitrogen, carbohydrates and microbial respiration had a positive effect on enzyme activities. A significant correlation values, up to 99%, was found among enzymes and they were responding similar to the environmental systems.