采煤沉陷后风沙土理化性质变化及其评价研究

VARIATION OF PHYSICO-CHEMICAL PROPERTIES OF AEOLIAN SANDY SOIL AT COAL MINING SUBSIDENCE AND ITS EVALUATION

对毛乌素沙地南缘补连塔矿采煤沉陷后风沙土理化性质的变化进行了研究。与对照区相比,沉陷2a间沉陷区土壤含水量普遍显著减小(p<0·05),而在沉陷2a后,沉陷区的地表沉陷边界处风沙土孔隙度显著增大(p<0·05),而容重、硬度显著减小(p<0·05),沉陷区局部地表开裂地段全氮、全磷含量显著减小(p<0·05),全钾与有机质含量无显著变化(p>0·05)。通过主成分分析得到研究区样地前2个主成分值的散点图,用以反映沉陷后风沙土理化性质的综合变异性,对采煤沉陷后土壤质量评价进行了探索。

In this paper, variation of physic-chemical properties of aeolian sandy soil on a subsided slope in Bulianta coal mining area located at southeast Mu Us Desert were studied. Compared with the control area, the subsided area significantly experienced loss of soil moisture within the two years after subsidence （p〈0.05）, increase in soil porosity （p〈 0.05） and decrease in bulk density and hardness of the aeolian sandy soil （p〈 0.05） in the upper layer along the fringes of the subsided area 2 years after the subsidence, and decline in total N and total P （p〈 0.05） in sections where cracks formed. However, total K and organic matter did not vary much （p〉 0.05） in the subsided area. A scatter diagram of the values of the first 2 principal components of the sample plots in the studied area were plotted out by means of PCA, reflecting comprehensive variability of the physic-chemical properties of the sandy soil after the subsidence and quality of the soil was assessed.