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以水稻土配制不同浓度(0.2％、0.5％和1％)的六溴环十二烷污染土壤,采用容量法和磷酸苯二钠比色法测定土壤中过氧化氢酶和磷酸酶的活性,研究六溴环十二烷对土壤酶活性(过氧化氢酶、磷酸酶)的影响,并通过配制不同浓度梯度的六溴环十二烷培养液,研究六溴环十二烷溶液对玉米、菜心、白菜和萝卜种子发芽和根伸长的影响.结果表明,土壤过氧化氢酶活性随着六溴环十二烷浓度的增大呈现先促进后抑制的趋势,0.2％处理对其活性促进作用最大;而土壤磷酸酶的活性随着六溴环十二烷浓度的增大而增大.六溴环十二烷对菜心种子发芽表现出先抑制后促进的影响规律;玉米种子发芽率差异性不显著,萝卜种子发芽受六溴环十二烷的影响不大;对白菜种子发芽表现出明显的抑制作用.当处理浓度超过90 mg· L-1时,与对照处理相比,六溴环十二烷对4种种子的根伸长均表现出明显的促进作用.总之,白菜种子发芽和根伸长对HBCDs最敏感,受其抑制程度较高.虽然高浓度HBCDs促进菜心和萝卜种子发芽,但其根伸长受抑制.HBCDs对土壤磷酸酶活性呈现激活作用,对过氧化氢酶呈现抑制作用.

Polluted paddy soil samples were prepared by adding hxabromocyclododecane at different concentrations (0.2％,0.5％ and 1％).The activity of catalase and phosphatase in soil was determined by volumetric method and disodium phenyl phosphate colorimetric method respectively to study the effects of HBCDs on soil enzyme activities (catalase,phosphatase).At the same time,the different concentration gradient culture medium of HBCDs was prepared to study the effect of HBCDs on seed germination rate and root length of Zea mays L,Brassica parachinensis,Chinese cabbage and Raphanus sativus L.The results indicated that activity of catalase in soil showed an initially enhancing and then inhibiting trend with the increasing concentration of HBCDs,and 0.2％ treatment was of the largest effect on activity promotion,while the activity of soil phosphatase was boosting with the increase of HBCDs.The germination effect of HBCDs on Brassica parachinensis seed prohibited at first and then promoted.The difference of seed germination rate of Zea mays L was not significant and HBCDs had little effect on the germination of Raphanus sativus L seeds.HBCDs had obvious inhibitory impact on Chinese cabbage seed germination.When the treatment concentration was higher than 90 mg· L-1,compared with the control treatment,HBCDs showed evident promoting effect on root elongation of 4 seeds in question.In a word,the germination and root elongation of Chinese cabbage were the most sensitive to HBCDs,and the degree of inhibition was higher.Although the high concentration of HBCDs stimulated Raphanus sativus L and Brassica parachinensis seed germination,but its root elongation was suppressed.The activity of soil phosphatase.