线虫群落对抚顺煤矸石山周边土壤可溶性盐污染的响应

于2006年5月对抚顺西露天矿西舍场煤矸石山周边的次生盐渍化样地进行可溶性盐含量和土壤线虫调查,经淘洗-过筛-离心漂浮法提取土壤线虫,应用线虫多样性指数和功能类群指数研究该区域土壤线虫群落的特征及差异。研究结果表明,抚顺西露天矿西舍场矸石山周围环境受到了煤矸石风化产生的以硫酸钠为主的可溶性盐污染, 但污染程度不高,土壤整体健康状况良好;共鉴定出线虫29属,其中Acrobeloides、Cervidellus 和Mesorhabtidis为优势属,随采样点距矸石山距离的增加线虫优势属也有所变化;研究区域中食细菌线虫和植物寄生线虫的绝对丰度高于食真菌线虫和捕食-杂食线虫的绝对丰度;土壤pH、矿化度、HCO₃^-、Cl^-、SO₄^2-、NO₃^-与线虫生态指数间存在显著相关关系。因此,通过开展线虫群落对土壤可溶性盐污染的响应研究,能为促进土壤生态系统健康发展提供科学依据。

Responses of soil nematode communities to soluble salt contamination around Gangue hill in Fushun

Soluble salt contents and soil nematode communities were investigated to evaluate soil pollution dues to soluble salt contents in the secondary salinization plots around the Gangue hill of Fushun West open-pit mine in May,2006.Six sampling sites were established along with the vertical direction to the Gangue hill between Tiantun and Qingtaizi,and site 1 was closest to the Gangue hill,while site 6 was the most distant to the hill.Annual herbs were more likely to distribute at sites that closer to Gangue hill,while perennial herbs became more and more common along with the increasing distance from the hill.The values of soil pH showed a increased trend from site 1 to site 6;the highest degree of mineralization,the highest contents of HCO-3,Ca2+ and Mg2+ appeared at site 1.In contrast,the contents of Cl-and SO2-4 were higher at site 6 than those at other sites.Soil nematodes were extracted from soil samples by using elutriate-sieving-flotation and centrifugation methods,and were used as bioindicators for assessing soil quality in the present study.Nematode abundance,diversity indices(Shannon-Wiener diversity index H′,Pielou evenness index J′,Simpson dominance index λ,trophic diversity index TD,specise richness SR),functional indices(Wasilewska index WI,maturity index MI),life history strategy(colonizer-persister),community structure and assemblage compositions were used to reveal the differences of soil nematode communities among different sites in this study area.The observed results showed that the environment in the sampling area was polluted by soluble sulfate which was a main production created by weathering of Gangue,but the degree of pollution was not very serious.In general,the soil was healthy in this area.Twenty-nine genera of nematodes were identified,Acrobeloides Cervidellus and Mesorhabtidis were the three most dominant genera at all sampling sites,and the dominant genera changed with the increasing distance to the Gangue hill.No significant differences in the values of λ,H′,MI and J′ were aboserved among 6 sites.MI showed a trend which is in inversely proportional to the distance from Gangue hill.Both the highest values of WI,λ and the lowest values of f/b,MI,J′ appeared at site 6.The absolute abundances of bacterivores and plant-parasites nematodes were higher than those of fungivores and omnivore-predators,which suggesting bacterivorous and plant-parasitic nematodes were more diffuse than fungivores and omnivore-predators.Soil nematodes communities were altered by soil elements only apart from contents of CO2-3,Mg2+ and Ca2+.The degree of mineralization and contents of HCO-3 positively correlated with the number of species(S) and SR,and soil pH and content of NO3-negatively correlated with nematode ecological indices.The content of Cl-positively correlated with WI,but negatively with TD.The contents of SO2-4 significantly correlated with WI,λ,J′,f/b and TD.The above results indicate that the responses of nematode communities to soluble salt contamination are effective to monitor the soil environment quality and can provide scientific bases to promote the healthy development of soil ecosystems.