矿区砷污染对土壤线虫群落结构特征的影响

Effects of Arsenic Contamination on Structure of Soil Nematode Community in Mining Area

对湖南省石门县雄黄矿区不同As污染程度土壤线虫群落结构特征进行了研究。共获得线虫27属,食真菌线虫滑刃属(Aphelenchoides)在3种土壤中均为优势属。食细菌和食真菌线虫分别为低As和中As土壤的优势营养类群,而植物寄生线虫为高As土壤的优势营养类群。低As和中As土壤的自由生活线虫成熟度指数(IM)和瓦斯乐斯卡指数(IW)显著高于高As土壤,但植物寄生线虫成熟度指数(IPP)和IPP/IM比值则表现出相反的趋势。可见,高As土壤的食物网受到As污染的干扰较大,群落环境质量较差。因此,土壤线虫群落结构对土壤质量或生态系统的变化具有很好的生物指示作用。

Population, community composition and trophic groups of soil nematodes in soils contaminated with arsenic （As） at three levels were studied. A total of 27 genera of nematodes were observed and dominated with Aphelenchoides in all the soils. Bacterivorous and fungivorous nematodes were dominant groups in soils, low and medium in As level, respectively, whereas, plant-parasites were the predominant group in soil, high in As level. Wasilewska index （Ⅰw ） and maturity index （ ⅠM ） of nematodes living freely in soils low and medium in As level were much higher than in soils high in As level, while the plant-parasites index （Ⅰpp） and Ⅰpp/ⅠM exhibited an opposite trend. The findings indicate that in soils high in As contamination level, the soil food web was heavily disturbed, and its soil environment quality for the community was much poorer than in soils low and medium in As level. It is, hence, suggested that structure of the nematode community is a potential indicator of changes in soil quality and ecosystem.