三七种植土壤中主要污染物累积及微生物特性变化

Pollutant Accumulation and Microbiological Characteristics Change in Notoginseng-planting Soils

通过野外采样及室内分析研究了三七不同种植年限土壤中主要污染物积累以及土壤酶活性和微生物功能多样性的变化特征。结果表明:Zn、Cr、Cd、As、Ni、Hg、Cu含量均超过国家土壤环境质量二级标准,其中As、Cd污染程度最严重;随着三七种植年限增加,土壤中重金属Cu、Cr累积量增加。有机氯农药五氯硝基苯及毒死蜱在土壤中也存在一定程度的残留,其平均含量分别为42.6和79.4μg/kg。随着三七种植年限的增加,土壤微生物碳源利用能力逐渐增强,群落物种均一度发生变化,而土壤脲酶、脱氢酶活性呈明显的先提高后下降的趋势。冗余分析表明As、Ni对土壤微生物活性及多样性起主要抑制作用。

The main pollutant accumulation and microbiological characteristics changes in soils with different notoginseng- planting years were investigated and analyzed. The results showed that the contents of all heavy metals, Zn, Cr, Cd, As, Ni, Hg and Cu exceeded the national soil environment quality standard, and the pollution levels of As and Cd were the most serious. With the increase of notoginseng-planting year, the contents of Cu and Cr in soil increased. Pentachloronitrobenzene and chlorpyrifos remained in the soils and the average contents were 42.6 μg/kg and 79.4 μg/kg, respectively. With the increase of notoginseng- planting year, the utilization of carbon sources by soil microbial communities was enhanced, the uniformity of microbial species changed, the activities of soil dehydrogenase and urease increased first and then decreased. Redundancy analysis showed that As and Ni inhibited microbial activity and diversity.