Evaluation Of Ecological Rehabilitation Of Open-Pit Mining Dumps By Bioremediation Method

The inspiration of this research is based on the existence problem of the reclamation in Guinea Bauxite Company CBG.In this mining,soil is removed and stocked in different soil dumps for the reclamation purpose but the dumps were found to be very damaged and not suitable for reclamation method used in CBG mining.Therefore,understanding the dump damage condition and choose suitable reclamation method become a big concern in the CBG mining area.Like the CBG mine dump condition,in china the Baorixile open-pit mining dump condition before the reclamation was not suitable for sustainable development condition.In the purpose of making open-pit mining dump to meet sustainable condition,a group of microbial choose based on their function and DNA,called in the thesis?microbial,was used to reclaimed the dump soil in the Baorixile mining zone I1 and H3 under project SKLCRSM17KFA08.Therefore,the purpose of this study is the evaluation of open-pit mine dump reclamation by bioremediation method.The question of this study is the analyzing of the positive impact of the bioremediation method by underlining the factors that impact on its efficiency.Aiming at problem of dump properties change and fertility capacity destruction,this thesis designs a test plan to evaluate soil dump condition.Experiment was done by sampling soil dump pile of different ages of storage,1,2,3,6,7,and 8 years of stockpiling time and testing of p H,Organic matter,Total Nitrogen,Total Phosphorus,Total potassium.The result shows soil dump loss its fertility condition during the time of storage.p H increased from 5.8 to 6.14.Organic matter decreased from 1.3%to 0.72%in correlation with soil dumps ages.The destruction of soil dump fertility capacity was obtained.As microbial was used to reclaimed mining soil dump condition,this thesis designs an experiment in the laboratory to evaluate the efficiency of microbial.For the reclamation of mining soil dump in the study area,?microbial bacteria group,was used.The experiment studies of selected plants based on their germination condition were done in the improved soil samples by?microbial and seed germination test with?microbial was done.Results show that germinated seed high and the germination rate on improved soil are higher than non-improved soil one and?microbial provides germination improvement for some plant such as Bromus and Leymus chinensis seed but for some seeds such as Tall fescue it can provide no improvement.The positive effect of?microbial was obtained.To evaluate the improvement of mining dump,during reclamation,samples were collected one time before the reclamation and one time every three months during reclamation for one year.The samples were tested of p H,Organic matter,Dissolved Nitrogen,Dissolved Phosphorus,Dissolved Potassium,Moist Content and Salinity.The result shows that p H was increased and varied between 8.55 to 8.23 and 8.46 to 8.11 base on different zones of reclamation.The organic matter increased from 5.35%to 6.24%in the reclamation zones against repectively 5.25%to 5.11%in the control zones.The dissolved Nitrogen,Phosphorus,Potassium were unstable.The improvement of mining dump during reclamation was obtained.For the evaluation of the reclamation result and impacted factor in the study area,Samples were analyzed of microbial activities,DNA,OUT,COG function,and vegetation was sampled and studied of diversity,cover,frequency and soil texture of different zones of the reclamation area was analyzed.The result shows the similarity between?microbial and soil samples microbial DNA,OUT and COG function.The plant cover and frequency varied base on different zones of the reclamation.As the reclamation zones H3 and I1 have different texture,in the H3 zone that has 17%of clay,plants were more diverse and abundant than I1 that has 7%of clay.This thesis shows that mining dump was improved during reclamation by bioremediation method but was impacted by high temperature during summer time by the decrease of Organic Matter and Moist Content,for Organic Matter in H3 zone,it was decreased from 6.44%to 3.52%and the Moist Content from 6.26%to 3.42%.For I1 zone the Organic Matter decreased from5.56%to 4.00%and the Moist Content 4.46%to 1.27%The soil texture also impacted on plant diversity in the reclaimed area.Bassia plant and Salsola plant were very dominant in all of the two zones with a frequency of 100%but the density of Bassia was higher in I zone than CH3zone,respectively at 12.31/m~2 and 4.93/m~2.There are 52 figures,15 tables,68 references in the thesis.