Abstract: The aim is to study the effect of plant growth on soil enzymes activity and microbe community structure. The maize is the experimental plant. The results show that microbe respiration and enzyme activity increase with elevated heavy metal concentration in soil and culture time. Low concentration Pb in soil would be helpful to enhance dehydrogenase and urease activity, but there is not significant effect on phosphatase activity. Meanwhile, planting maize would be helpful to alleviate the effect of Cd and Pb on phosphatase and urease activity and enhance soil respiration, and decrease the inhibition for dehydrogenase and urease activity under Cd and Pb stress, whereas enhancing the ecological dose value for inhibiting phosphatase avtivity is not significant. The effect of Pb on soil polymorphic bands is smaller than that of Cd, and planting maize would increase the polymorphic value and DNA richness. Therefore, there are important meaning to enhance plant diversity for alleviating heavy metal toxicity, increasing microbe community diversity and enhancing soil health.

Key words: ecological dose, soil enzyme activity, gene polymorphic, soil health

摘要： 主要研究重金属污染下植物生长对土壤酶活性和微生物群落结构的影响。玉米为供试植物。结果表明: Cd, Pb 污染下土壤呼吸强度和酶活性随重金属浓度和培养时间增加而逐渐减小, 土壤中低浓度Pb可促进脱氢酶和脲酶活性, 但对磷酸酶起抑制作用; 种植玉米可减轻 Cd, Pb 对磷酸酶和脲酶的影响, 促进土壤呼吸, 但对提高脱氢酶活性作用不显著, 同时, 种植玉米有利于降低 Cd, Pb 对脲酶和脱氢酶的抑制作用, 但对提高磷酸酶的抑制作用阈值并不显著;Pb 对土壤基因多态性的影响要小于Cd, 种植玉米有利于提高土壤基因多态性及基因丰富度。因此提高植物多样性对减轻重金属毒害, 增加微生物群落多样性和促进土壤健康具有重要意义。

关键词: 生态剂量, 土壤酶活性, 基因多态性, 土壤健康