Evaluation On Ecological Restoration Quality Of Typical Dry-exhausted Iron Tailings Reservoir In Chicheng

The mine wasteland is a major hidden danger in the mining area that causes damage to the ecological environment and water and soil loss.The consequences of the mine waste seriously affect the natural ecological environment and human survival.Research on the ecological restoration of mine abandoned land at home and abroad continues.However,the current problem is that there are no systematic evaluation indicators for the ecological recovery project of the tailings pond,which leads to unclear goals in the environmental management of tailing ponds and lacks overall planning.Chicheng County is one of the important metal mining cities in Zhangjiakou,rich in mineral resources,high quality metal minerals,and better exploitation of resources.To evaluate the community characteristics of tailing reservoirs after ecological restoration in Chicheng County and construct a quality evaluation method suitable for the ecological restoration of dry tailings ponds.The criteria for determining the success of ecological restoration and the methods adopted for recovery ean achieve the recovery goals.With scientific guidance,this paper takes four dry iron tailings reservoirs in Chicheng County as the research object,establishes an evaluation index system for ecological recovery of tailing ponds using AHP AHP,and adopts the vegetation communities,soil nutrients,and the surrounding of different tailings reservoirs.The natural community conducts sample plot surveys and conducts fluzzy comprehensive evaluation according to different vegetation restoration environments.The results show that:(1)Among the four tailings stocks surveyed,the species composition is relatively simple and the species of trees are single.There are only 5 species of tree species within the sample area.The main tree species are artificially planted Chinese pine,larch,and poplar trees;The recovery level of the platform environment in the tailings reservoirs of Gunga Township,B,Longguan Town,and Tianjiayao tailings reservoir reached the recovery standard.(2)Evaluate the ecological restoration effects of the four tailing iron ore tailings deposits in Chicheng County.The results show that:in the comprehensive rating,the overall evaluation result of the tailings pond A in the Guoliang Township was poor with a score of 66.8;The comprehensive evaluation of mine bunker B was moderate,with a score of 72.5;the assessment result of Longguan town tailing pond was up to the standard,with a score of 84.6;the comprehensive evaluation of tailing pond of Tianjiayao town was good,with a score of 92.5,integrating the above analysis,the ecological restoration quality of each tailing pond.The order of the final score is:Tianjiayao tailings>Longguan tailings>Gunyao tailings B>Gunyao tailings A,Taijiayao tailings and Longguan tailings The restoration quality of the reservoir ecology reached the recovery standard,and the tailing reservoir A and the tailings reservoir B of Gunliang Township did not meet the restoration standards.(3)Since the recovery period of the tailings reservoir in Gunliang Township is less than 1 year,the herbaceous plants occupy a dominant position in view of the community structure composition,and the species diversity index is significantly higher than that of the shrub community,reflecting that the overall community structure is simple;In the future vegetation restoration,the proportion of shrubs and arbors should be increased,and measures should be taken to ensure the survival rate.The organic matter and total N in soil nutrients are one of the important factors limiting the vegetation restoration.(4)At the restoration of the tailings bank B of Kuoliang Township for 2 years,only some indicators reached the restoration standard,but the overall recovery did not reach the standard.Accompanying you,the ecological restoration level of the shrub layer in the arbor layer and side slope of the platform reached the recovery standard;the quick-acting K,total effective N,and organic matter in the recovered environment were all lower than the natural vegetation environment,and appropriate potassium fertilizer and nitrogen fertilizer needed to be applied during the restoration process.·(5)The ecological recovery of the tailing pond in Longguan Town has reached the recovery standard as a whole,but it takes a long time for the shrub layer to recover its diversity in order to reach the level of restoration standards.The available soil nutrients,quick-acting P and quick-acting K,in different restoration environments were higher than the restoration standards;the total N and organic matter in the four restoration environments were much lower than those in the natural controls.The above analysis shows that the total N and lower organic matter content are the main limiting factors for the vegetation recovery of the tailings pond in Longguan Town,and nitrogen fertilizers need to be properly added during the vegetation restoration process.(6)The ecological recovery of tailings pond in Tianjiayao Town reached the standard of restoration.The richness S and evenness E of the arbor layer,shrub layer,and herbaceous layer were all greater than the restoration standards;the available P content in different restoration environments was greater than the recovery standard;the available K content Less than the restoration standard;full effect N is closer to the natural vegetation environment;organic matter content is greater than the natural vegetation environment.