伊犁河谷煤矿开采对土壤重金属污染、养分及酶活性的影响

Effects of coal mining on soil heavy metal pollution,nutrient and enzyme activities in Yili valley

为了评价伊犁河谷地区煤矿区土壤的质量和受污染的程度,以及矿区周边农用地土壤的质量,通过野外采样和实验室分析,调查了伊犁河谷地区两处煤矿和周边耕地的土壤,测定了0~40cm深度土壤中的Cu、Cd、Cr、Zn、Pb 5种重金属元素的含量,采用单因子指数法和内梅罗综合污染指数法进行评价.同时测定了土壤速效氮、速效磷、速效钾、有机质以及土壤蔗糖酶、脲酶、过氧化氢酶的活性.结果表明,所选的两处煤矿矿区土壤重金属污染严重,其中Cd超标最为明显,庆华煤矿样地重金属Cd的单因子污染指数达到了5.97;铁厂沟煤矿达到了9.54.庆华煤矿的内梅罗指数达到了4.47,铁厂沟煤矿的内梅罗指数达到了7.06,两地均属于重度污染.煤矿周边的农用地也受到了一定程度的污染,庆华煤矿周边玉米地样地的内梅罗指数达到了2.90,属于中度污染,而在铁厂沟煤矿附近的达达木图乡两块农用地内梅罗指数达到了3.94和3.58,均属于重度污染;所选煤矿区土壤及其周边农用地土壤养分含量偏低,土壤酶活性与土壤养分含量呈显著正相关,重金属含量与土壤酶活性呈负显著或极显著相关,但养分与重金属之间相关性不显著.

In order to access the soil quality and pollution level of coal district in Ili River,as well as the soil quality of agricultural land around the district,the essay investigated two coal mines in Ili River area and the soil around them via field sampling and laboratory analysis.The content of five heavy metal elements：Cu,Cd,CR,Zn,Pb in the soil of 0-40 cm deep were measured and assessed by single factor index method and Nemerow Pollution Index.In addition,soil available nitrogen,available phosphorus,available potassium,soil organic matter and the activity of soil saccharase and urease,as well as catalase were also measured.The results showed that the soil of the two investigated coal mines were severely polluted by heavy metal elements,among which,Cd was the most polluted element：Qinghua Coal Mine＇s Single Factor Index of Cd reached 5.97,and Tiechanggou Coal Mine turned out to be 9.54.When it came to Nemerow Pollution Index,Qinghua Coal Mine had the Index of 4.47,and Tiechanggou Coal Mine＇s was 7.06.The two tested Mine were both heavily polluted.In terms of the agricultural land around the two coal mines,it was found that the corn sample land around Qinghua Coal Mine was moderately polluted,occupying the Nemerow Pollution Index of 2.90;while two sample lands in Dadamutu Area around Tiechanggou Coal Mine were heavily polluted,and the Nemerow Pollution Index were separately 3.94 and 3.58;the tested soil in the Mine and the agricultural land around turned out to be at a low level of soil nutrition,and the soil enzymatic activity had positive correlation with soil nutrition content.The content of heavy metals has a negative or extremely significant correlation with soil enzyme activity,but there is no significant correlation between nutrients and heavy metals.