Benefits Of Soil Erosion Harness In Spoil Dump In Open-pit Coal Mine In Loess Area

Mining process in open-pit mine in Loess Area includes excavation, transportation, abandon, and dwelling, which can result in dump soil layer disorder, soil compaction, microhabitat destruction, and soil erosion, even landslide and debris flow etc..In this research, theories, methods and experiences of soil erosion harness around the world have been compared respectively fromspatial scale, time scale and benefit expression, aiming at controlling the cost and improving business efficiency by measuring the relationship between input and output, and finally providing guidance for dump soil erosion harness. The results are as follows:(1) Based on ecology and land economics theories, studies on dump, soil erosion harness and efficiency has been analyzed, and computational models of the monetization of economic, social and ecological benefits have been established by ecosystem services value coefficient method, the market comparison approach, field investigation method and literature review method.(2) Taking the internal dump of ATB opencast mine as example, it is measured by field experiments that soil erosion amount in un-reclaimed stage in certain time has reached 961kg/m2. Besides, the soil erosion in the northeast of stage is the most serious. The reasons are as follows. First, the elevation of west and south in this stage of dump is higher than that of east and north. Second, there is no any timely engineering measure and vegetation restoration measure since this stage has been formed. Third, the rainfall is heavy in summer in the study area, and the northeast of stage has been washed seriously.(3) Compared with un-reclaimed land, the soil p H is reduced after soil erosion harness, but it is still higher than the original landscape. The depth of soil layer 0-25 cm, soil porosity significantly increasedafter reclamation. The soil bulk density of un-reclaimed dump is 1.92g/cm3, much higher than the reclamation dump and the geographical landscape.(4) It is concluded that the cultivated area of alfalfa should be increased since alfalfa makes the greatest contributio n to economic and ecological benefit.(5) Based onthe ecological service value coefficient of equivalent, the equivalent value in Shanxi province has been calculated, namely 0.77.(6) The benefit value of economic, ecology, society of soil erosion harness respectively are 198100.00 yuan/hm2, 34209.82 yuan/hm2, and 6187.91 yuan/hm2, and soil erosion harness cost is 105983.25 yuan/hm2.