Effects Of Bioactivc Humic Acid On Rebuilding Of Soil Microbial Ecology In Mining Wastelands

Based on the original ecological restoration of wastelands in Pingshuo opencast mine area andcombining investigation outdoor with simulation experiment indoor, this paper studied the restoration ofsoil microbial ecology and probed into the effect of bio-active humic acid (BHA) on the rebuilding ofsoil microbial ecology in wastelands.1. Investigation outdoor based on ecological restorationPingshuo opencast mine created a precedent of mine land reclamation work in our country, andform a soil one-stop production operation way including mining, dumping, reclamation and planting,and about2000hm2and50%of damage land has been reclaimed into the forestland, grassland orfarmland, but the reclamation efficiency was not ideal. In research area, the lack of soil organic matterand nitrogen and the low of soil biological activity severely limited the ecological reclamation ofwastelands. Linear relationship between soil quality comprehensive score(y) based on principalcomponent analysis of reclamation wastelands and its reclamation year (x) was y=0.2163x-1.0418（R2=0.8137）, and the comprehensive score expression was mainly reflected in soil organic matter,total nitrogen and soil microbial ecology index as main restrictive factors. According to this expression,if the quality of wastelands wanted to achieve the original landscape level, the time of ecologicalrestoration would be18years at least. In addition, the research on the sensitivity and the correlationanalysis of the soil quality index found that soil microbial ecology indexes were more sensitive andcomprehensive than chemical and physical properties. It’s highly necessary to pay attention to thereconstruction of the soil microbial ecology in the reclamation process of the wastelands.2. Simulation experiment indoor based on microbial ecological reconstruction with BHABased on the results of investigation outdoor and the characteristics of restrictive factors inecological reclamation of wastelands, that simulation experiment indoor based on microbial ecologicalreconstruction with BHA had been designed. The simulation experiment indoor showed that theapplication of BHA increased culturable microorganism quantity, plant volume, fungi diversity indexand soil advantages fungi community structure stability, and partly removed the adverse impact of thefertilizer application on soil microbial ecology. BHA brought about the interaction between the aerialpart and underground part, and the plant volume was significantly positively related with soil culturablebacteria, fungi and total microorganism quantity and positively related with soil fungi diversity index.The treatments of top three comprehensive results by score in turn were30kg/Mu BHA+50kg/Mucompound fertilizer,45kg/Mu BHA+50kg/Mu compound fertilizer and30kg/Mu BHA. Under thecondition of BHA’s single application, the result of30kg/mu BHA treatment was best and its culturablemicroorganism quantity, plant volume and fungi diversity index was respectively increased by96%,34%and6.5%compared with blank control. Under the condition of BHA and fertilizer mixed application,the result of50kg/Mu BHA+50kg/Mu compound fertilizer treatment was best, and its culturablemicroorganism quantity, plant volume and fungi diversity index was respectively increased by94%,70% and15%compared with blank control.3. Comparison between the simulation experiment indoor and the investigation outdoor(1) The study of simulation experiment indoor based on microbial ecological reconstruction withBHA was more comprehensive than the investigation outdoor based on ecological restoration. In theplant-soil-microorganism system, the investigation outdoor only focused on the restoration of aerial part,and ignored the restoration of the underground part, while simulation experiment indoor was on thebasis of vegetation reclamation and took the rebuilding of soil microbial ecology into consideration.(2)Simulation experiment indoor based on microbial ecological reconstruction with BHA was benefit forthe settlement of limiting factor in wastelands reclamation. For example, urea application with BHAcould eliminate adverse impact on wastelands soil microbial ecology from urea single application andcompound fertilizer application with BHA could enhance wastelands soil microbial ecologyreconstruction of compound fertilizer single application.Based on the above analysis, it’s better to solve the disorder of the microbial ecology and the lowefficiency of ecological restoration by the application of BHA.