兽药磺胺间甲氧嘧啶对土壤呼吸及酶活性的影响

为评价兽药污染对土壤生态环境造成的潜在环境风险，采用室内培养的方法，研究了兽药抗生素磺胺间甲氧嘧啶对黄潮土土壤微生物呼吸及土壤酶活性的影响。结果表明，磺胺间甲氧嘧啶可显著影响土壤呼吸强度，抑制率和激活率分别可达72%和254%，药物对土壤酶活性的影响小于其对土壤呼吸强度的影响。在添加磺胺间甲氧嘧啶的前11 d，其对脲酶活性的影响主要以抑制作用为主；药物对蔗糖酶活性的影响较为明显，最大抑制和激活率可分别达到18%和30%；磺胺间甲氧嘧啶作用于过氧化氢酶和磷酸酶主要表现为激活效应，最大激活率分别为17%和25%。在试验浓度范围内，土壤微生物呼吸及酶活性的抑制率或激活率呈现一定的波动性。

Effects of Sulfamonomethoxine on Soil Respiration and Enzyme Activity

The animal excrements containing veterinary drugs manured into field soils would result in agricultural soil pollution, and which drew an important potential threat on the human health and ecosystem. The effects of sulfamonomethoxine on soil respiration and enzyme activity were studied in the yellow moist soil by indoor cultivating to evaluate the potential toxicological effects of veterinary drugs. The results showed that soil respiration was influenced obviously under the stress of sulfamonomethoxine, the inhibition rate and activation rate reached 72% and 254%, respectively. The effect on enzyme activity by sulfamonomethoxine was much less than the soil respiration, which demonstrated the fact that soil respiration was much more sensitive under the stress of the drug. Sulfamonomethoxine had inhibition or activation effect on the activities of the tested soil enzymes. Urease activity was inhibited before the 1 1th day of the test time; Invertase activity was inhitited and stimulated significantly, the ratio reached 18% and 30%, respectively. While catalase activity and phosphatase activity in soil were maily activated, the maximal activation rates reached 17% and 25%, respectively, under the stress of the drug; In addition, the activities of soil respiration and the four tested soil enzymes fluctuated with time.