双草醚对土壤呼吸作用及土壤酶活性的影响

通过模拟试验研究了除草剂双草醚对土壤呼吸强度和土壤酶活性的影响。结果表明，双草醚施用初期刺激土壤呼吸作用但随后产生抑制作用，施用20d后，浓度愈大对土壤呼吸作用的抑制愈明显;双草醚轻微抑制土壤中过氧化氢酶活性，21d后基本恢复正常;双草醚对脲酶活性有刺激作用，且低浓度处理酶活性明显高于高浓度处理。统计分析结果表明双草醚属于低毒农药。

Effects of Herbicide Bispyribac-sodium on Soil Enzyme Activities and Soil Respiration

Effects of herbicide bispyribac-sodium on soil respiration and the activities of catalase, urease were studied by using simulated experiment in laborotary. The results showed that after application of bispyribac-sodium with concentration of 1.5, 15, 30, 60 and 120 mg/kg dried soil, compared with the control, soil respiration was stimulated at the beginning but reduced slightly at 13d, and after the third week, the soil respiration was strongly depressed by higher concentration. The catalase activity in soil was slightly depressed during the early period and recovered after 21days. The activity of urease was stimulated after application of bispyribac-sodium, and the lower concentration of bispyribac-sodium had more effects and lasted a longer time. Bispyribac-sodium belonged to a low toxicity herbicide.