Study On Preparation And Application Of Microbial Agents In Reclamated Soil Of Mining Area

In view of the outstanding problems of poor soil physical structure,poor nutrients and low microbial activity in the soil of new coal mine reclamation,the soil of long-term positioning test base in Changzhi City and Gujiao City of Shanxi Province was taken as the research object.Through the screening of fertile soil microbial strains,functional analysis,combined with bioactive substances,the preparation of fertile soil microbial agents was completed,and the corn planting effect test was carried out.The results showed that the combined application of soil microbial agents and organic materials significantly improved the nutrient and microbial activity of reclaimed soil,and the biomass and nutrient absorption of maize.The main findings are as follows:(1)Five functional microorganisms were obtained,including nitrogen-fixing bacteria(GN-3),potassium-solubilizing bacteria(JK-3),inorganic phosphorus bacteria(WP-3),organic phosphorus bacteria(YP-3)and growth-promoting bacteria(LB-3).Compared with the control,the nitrogenase activity of GN-3 was increased by 188.7%,the potassium release rate of JK-3 was increased by 57.6%,the phosphorus release rate of WP-3 was increased by 175.9%,the phosphorus release rate of YP-3 was increased by 132.8%,and the IAA secretion rate of LB-3 was increased by 120%.(2)According to 16S rDNA identification,GN-3 belongs to Assoil bacteria,WP-3 belongs to Enterobacter arbori,and YP-3,JK-3 and LB-3 belong to Serratia marxis.Fertile soil microbial agents were prepared by mixing functional bacteria and bioactive substances in a certain proportion.(3)The combination of fertile soil microbial agents and organic materials significantly increased soil nutrient content.Among them,improvement of total nitrogen,organic matter,alkali-hydrolyzable nitrogen,available phosphorus and rapidly available potassium in the treatment of "NPK+organic fertilizer+straw+bacterial agent" was highest,and the difference with other treatments is significant.(4)The microbial activities and enzyme activities in the soil were significantly increased by the combination of microbial agents,community diversity and organic materials applied in fertile soil.After 80 days of maize planting,the number and diversity of soil bacteria,fungi and actinomycetes,as well as the activities of nitrogen enzyme,carbon enzyme,phosphase and oxidase in the treatment of "NPK+organic fertilizer+straw+bacterial-agent soil" showed the best performance,which was significantly higher than that in other treatments.(5)The combination of fertile soil microbial agents and organic materials significantly improved the dry matter quality and nutrient uptake of maize plants.At 80 days after maize planting,the biomass and nutrient uptake of maize under the treatment of "NPK+organic fertilizer+straw+bacterial agent soil" were the highest.The synergistic application of microbial agents and organic materials in fertile soil can improve the nutrient content of reclaimed soil,increase soil microbial activity and promote crop growth.Therefore,the microbial agent can be further developed and used to develop the microbial agent for fertile soil,and further tests can be carried out in the field.