Short-term response of soil enzyme activities in a chlorpyrifos-treated mesocosm: Use of enzyme-based indexes

摘要: Abstract Soil enzyme activities have been long used as indicators of soil contamination, and their integration into numerical indexes microbial functional diversity is a practical approach in the environmental risk assessment pollutants. However, suitable need to be developed standardized for monitoring deterioration quality by agrochemicals. Herein, mesocosm study was performed examine short-term responses selected chlorpyrifos (Lorsban ® 4E). Hydrolases (carboxylesterase, acid phosphatase, β-glucosidase, urease protease) oxidoreductases (dehydrogenase catalase) were measured Andisols 14 d after an application with two doses (4.8 24 kg a.i. ha −1 ) chlorpyrifos. Both rates caused strong inhibition carboxylesterase (62–78% controls), phosphatase (56–60%) β-glucosidase (43–58%) activities. activity also reduced pesticide-sprayed soils indicated decreased dehydrogenase (47%) catalase (38%) compared control soils. only showed dose-dependent response rate. An vitro trial further provide evidence direct interaction between β-glucosidase) pesticide (chlorpyrifos its main metabolites chlorpyrifos-oxon 3,5,6-trichloro-2-pyridinol). Results these assays that directly affected and, at less extend, chlorpyrifos, whereas variations both likely dependent on changes activity. Urease protease did not change pesticide-treated pesticide-free Despite absence N-cycling activities, four enzymatic (geometric mean, weighted “treated-soil index” [T-SQI] “integrated biological response” [IBRv2] index) significantly lower chlorpyrifos-sprayed controls. Moreover, there significant ( r 2  = 0.87, P