Effect Of Artificial Vegetation Restoration On Soil Nutrients The Content Of Heavy Metals In Opencast Coal Mine Dump

The Da Hinggan mountain is the important state-owned forestry region in china, which status and ecological function is unable to be instead of, and established within the territory of MoHeXian GuLian river opencast coal mine, in the process of mining, the surrounding environment and ecological equilibrium has be destroyed. Take the coal mine dump in Gulian River for the study,in2009Mongolica and larix hippophae rhamnoides in vegetation restoration and afforestation, for different planting area, soil nutrient and heavy metal element content for detailed research in2012, the results show that:1. After afforestation, the nutrient content in soil are improved, especially in the organic matter content increased significantly, average increased172.22%,total nitrogen, total phosphorus, total potassium and available potassium respectively to improved22.01%、25.60%、7.52%and22.03%. Seabuckthorn planting area, on average, increase soil nutrient content of big, secondly is larch and mongolica planting area, respectively1.63,1.39, and1.16times the average content of the not plantin area. After four years of afforestation, replace with bare-root forestation effect on the soil nutrient content is the same, each nutrient content than control are improved, but replace with bare-root afforestation on the improvement of the nutrient content was not significant.2. The afforestation tree species can reduce the content of soil heavy metals Cu, Mongolica、larix and Seabuckthorn planting area is not planting area respectively reduced18.82%、14.17%and18.01%; on the influence of the Mn content and the influence of Cu content is different, Mongolica planting area less content of planting area increased by1.89%, Larch planting area decreased10.87%, Seabuckthorn planting area increased4.19%; on the influence law of the Zn content and Cu content identical, Mongolica、Larix and Sea Buckthorn respectively decreased16.93%、24.04%and22.30%; on the influence law of the Pb content and Mn content identical, Mongolica increased19.65%、Larix and Sea Buckthorn respectively decreased7.94%and11.72%.3. Afforestation of replace with out-soil afforestation and bare-root reduces the content of heavy metal elements Cu, are not planting area of0.78and0.88times respectively; Replace with out-soil planting area for Mn content is1.17times, bare-root afforestation for0.79times; Zn contents of replace with out-soil and bare root planting area is0.73and0.85times; Pb contents of replace with out-soil and bare root planting area is1.01and0.99times.4. The afforestation tree aboveground biomass and soil nutrient and heavy metal Cu, Mn, Pb and Zn correlation analysis, Mongolica and Larix on soil available potassium, available phosphorus, Cu, Pb and Zn negative correlation relationship, Seabuckthorn on soil Cu, Zn and Pb three kinds of heavy metal elements negative correlation relationship, other appeard positive correlation relationship.5.From Nemerow integrated, without afforestation measures on the control of the pollution degree is the largest, followed by mongolica and larix planting area, Seabuckthorn planting area pollution the least,but they belong to light pollution. Different planting area, all kinds of metal elements, single factor pollution laws are different, Seabuckthorn and Larix has the same rule is Cu>Zn>Pb>Mn, Mongolica planting area is Cu>Pb>Zn>Mn,but the major pollutant is Cu.6. Afforestation of replace with out-soil in plants of plant height, base diameter, biomass growth is stronger than the bare root planting area, Mongolica replace planting area of plant height, base diameter, biomass is bare root planting area increased, respectively2.69%、9%and25.02%, Larch respectively increased6.85%、6.72%and21.15%, Seabuckthorn respectively increased1.72%、7.61%and13.09%.