青海木里煤田聚乎更矿区土壤肥力及重金属风险评价

木里煤田聚乎更矿区在开采煤炭资源的同时，破坏了矿区生态环境。通过对矿区土壤肥力指标及重金属指标的测定，采用主成分分析法、潜在生态危害指数法对土壤肥力和重金属风险进行评价。结果表明:木里煤田聚乎更矿区土壤整体呈碱性，有机质、全氮、速效钾含量较丰富而速效磷含量较缺乏，呈富氮富钾贫磷的特点，三号井田土壤中各肥力指标含量最好；土壤肥力综合得分分别为:哆嗦贡玛井田(–0.113)、九号井田(0.081)、八号井田(–0.369)、五号井田(–0.034)、四号井田(–0.145)、三号井田(0.692)，三号井田土壤综合肥力最好；木里聚乎更矿区土壤中6种重金属的生态危害强度由弱到强的顺序为Cr、Pb、Cu、Hg、As、Cd，各井田土壤重金属风险评价结果均为轻微生态危害程度。综上，矿区排土场土壤肥力质量整体较差，重金属处于低风险状态，排土场土壤可作为土壤重构中的充填基质，但需混合牲畜肥料、有机肥来提高重构土壤的肥力质量，研究结果将为木里煤田聚乎更矿区土壤重构和植被修复提供基础与依据。 

Soil fertility and heavy metal risk assessment in Jvhugeng mining area,Muli Coalfield,Qinghai Province

The mining of coal resources at the Jvhugeng mining area, Muli Coalfield, has damaged the ecological environment of the mining area. Through the determination of soil fertility indexes and heavy metal indexes in the study area, soil fertility and heavy metal ecological risks are evaluated by the principal component analysis method and the potential ecological hazard index method. The results show that the soil in the mining area is alkaline as a whole, rich in organic matters, total nitrogen, and available potassium, but lacking in available phosphorus. It has the characteristics of being rich in nitrogen potassium and poor in phosphorus. The soil fertility indicators in the No.3 minefield are the best. The comprehensive scores of soil fertility respectively are Duosuo Gongma minefield(?0.113), No.9 minefield(0.081), No.8 minefield(?0.369), No.5 minefield(?0.034), No.4 minefield(?0.145), and No.3 minefield(0.692). The soil fertility of the No.3 minefield is the best. The order of the ecological hazard intensity of the six heavy metals in the soil of the mining area from weak to strong is Cr, Pb, Cu, Hg, As and Cd, and the results of the risk evaluation of those heavy metals in the soil of each minefield show a slight ecological hazard. In conclusion, the overall fertility quality of the slag hill soil in the mine area is poor, and the heavy metals are of low risk. The slag hill soil could be used as the soil substrate in soil reconstruction, but it needs to be mixed with livestock manure and organic fertilizer to improve the fertility quality of the reconstructed soil. The results of the study provide a basis for soil restructuring and vegetation restoration in the Jvhugeng mining area of the Muli Coalfield.