Abstract:

An indoor simulation experiment was carried out to study effects of trichlormethane on activities of four soil enzymes (catalase, urease, dehydrogenase and acid phosphatase). Potassium permanganate titrimetric method, Conway diffusion method with soil in the outer chamber and boric acid-indicator solution in the inner chamber, TTC method and p-nitrophenyl phosphate (PNPP) colorimetric method were used to detect the activities of catalase, urease, dehydrogenase and acid phosphatease. Results showed that trichlormethane had a little effect on catalase and dehydrogenase activities within the designed concentration from 0.03mg/kg to 45mg/kg. Soil urease and soil acid phosphatase had activities within the range of 0.283~0.977 mg/g and 0.168~0.742 mg/g/h, separately. When trichlormethane was in the designed concentration from 0.03 mg/kg to 45 mg/kg, soil urease activities were stimulated, while soil acid phosphatase activities were inhibited by 1.33%~115% and 2.5%~97%, respectively. It indicated that soil urease and acid phosphatase could be used to a certain extent as indicators of soil pollution by trichlormethane.