古莲河煤矿不同造林树种对土壤养分及重金属含量的影响与评价

Effect of Different Afforestation Tree Species on Soil Nutrients and Heavy Metal Content and Its Assessment in Coal Mine Waste Dump of Gulian River

以大兴安岭古莲河煤矿排土场为研究对象,分析不同造林树种对土壤养分及重金属元素污染的改良效果。结果表明:各造林地土壤养分含量均有所增加,沙棘、落叶松和樟子松造林地土壤养分含量平均值分别为对照地的1.61,1.37,1.15倍;并且各造林地重金属元素含量也均有所下降,沙棘、落叶松和樟子松造林地重金属元素含量分别为对照地的0.95,0.86,0.97倍,土壤内梅罗综合污染指数分别为1.24,1.29和1.28,与未造林排土场内梅罗综合污染指数1.50相比明显降低,但都属于轻度污染。试验说明植树造林不但能提高土壤养分含量,还能吸收、固定土壤中的重金属元素,从而降低土壤污染程度。

Taking the coal mine dump in Gulian River as the study object,the effects of different woodland on the improvement of soil nutrients and heavy metals pollution were analyzed.The results showed that soil nutrients content were increased in different woodland,and the average of soil nutrients was increased 1.61,1.37,1.15 times than that of control,soil heavy metals content was also decreased 0.95,0.86,0.97 times than that of the control.Nemerow integrated pollution index in different woodland was 1.24,1.29 and 1.28,respectively,and was significantly lower than that of control,which Nemerow pollution index was 1.50.Results indicated that the soil belonged to slight pollution.This study demonstrated that forestation would not only improve the soil nutrient content,but also absorb the fixed soil heavy metal elements,thus reduced the degree of soil pollution.