三氯甲烷对红壤酶活性影响的模拟研究

Soil Enzyme Activity as Affected by Trichlormethane

采用模拟实验方法,研究了不同浓度三氯甲烷对红壤中过氧化氢酶、脲酶、脱氢酶、酸性磷酸酶活性的影响。过氧化氢酶、脲酶、脱氢酶、酸性磷酸酶活性分别采用高锰酸钾滴定法、扩散法、TTC法、对硝基苯磷酸盐法测定。结果表明:试验浓度范围内三氯甲烷对过氧化氢酶、脱氢酶活性影响很小。三氯甲烷可明显激活脲酶活性,抑制酸性磷酸酶活性,两种酶的活性范围分别为0.283～0.977mg/g,0.168～0.742mg/(g·h)。相对于对照,在0.03～45mg/kg范围内,脲酶活性增加了1.33%～115%,酸性磷酸酶活性降低了2.5%～97%,说明脲酶和酸性磷酸酶可揭示土壤受三氯甲烷污染的程度。

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 0.03 mg/kg to 45 mg/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.