The Health Evaluation Of Grassland Ecosystem In Baorixile Mining Area And Surrounding

In this paper,takes Shenhua Baorixile mining area and surrounding grasslands as the research object,on the basis of ecological investigation,Analysis the changes of health factors in each study area;Establishing an indicator system about grassland health.The expert scoring method was used to grade the results of each index.The formula of attribute index was used to obtain each attribute index.According to the attribute index,the grassland health was comprehensively evaluated.The results are as follows:(1)The analysis of species diversity shows that,the natural grassland is affected by the outside world,so the number of species,diversity index and stability are lower than those in the control area;The number of species in the waste dump is not much than the control area,species are evenly distributed in the sample plot,but the number of individuals per unit area in the study area is large.Analysis of diversity index about different belt transect of natural grassland on different gradients from mining area shows that,natural grassland is greatly affected by grazing and less affected by coal mining.Analysis of species similarity in the study area shows that,the similarity between the waste dump and the control area is greater than the natural grassland,and the recovery effect of the dump is closer to the control area.(2)The comparison of soil mineral nutrients shows that,the total nitrogen and available phosphorus of natural grassland are lower than the control area,and the total nitrogen is significantly lower than the control area,but beacaus of the grazing,available nitrogen is higher than the control area.Total nitrogen,available phosphorus and available nitrogen in the waste dump are lower than the control area,this indicating that there is a certain gap between the study area and the primary vegetation in the control area,and the study area is in the stage of restoration succession.Total nitrogen and available nitrogen in natural grassland are significantly higher than the waste dump,and there is no significant difference in available phosphorus.The comparison of soil bulk density,water content and organic matter shows that,organic matter in natural grassland is significantly lower than the control area,but the comparison of soil bulk density and water content is not obvious.The bulk density of the waste dump was significantly higher than that of the control area,and the organic matter was significantly lower than the control area,but there was no significant difference in water content.Compared with the waste dump,natural grassland has significant differences in bulk density,water content and organic matter,which bulk density and water content are significantly lower than the dump,and organic matter is significantly higher than the dump.Analyse the water content,organic matter and bulk density of different research areas in the same soil layer shows that,water content,waste dump>control area>natural grassland,bulk density.Waste dump>natural grassland>control area,organic matter content,control area>natural grassland>waste dump.The comparison of soil water content,organic matter and bulk density in different soil layers of natural grassland shows that there is no significant.The water content,organic matter and bulk density of soil in different soil layers of the waste dump are significantly different.Except for water content,the index content of upper soil layer is significantly higher than that of lower soil layer.(3)According to the soil erosion index measurement in the study area,the water flow trace rill,litter movement and wind erosion value are all 0.(4)The grassland health evaluation in the study area shows that,the comprehensive evaluation result of grassland health in the natural grassland evaluation area is 3.705,the grassland health status is good,the comprehensive evaluation result of grassland health in the dump evaluation area is 4.1498,and the grassland health status is good.The results showed that the natural grassland was affected by grazing,but its utilization was reasonable.Artificial restoration effect of waste dump is better.