Effect Of Different Plant-amendment On Soil In Arid Mining Area

Coal occupies an important position in China’s energy consumption and is a pillar industry of China’s economic development.However,coal mining has seriously damaged the ecological environment,resulting in arid and barren soil in mining areas,difficult plant growth and even serious mine geological disasters.Therefore,it is of great practical significance to improve and utilize the soil in arid mining areas reasonably.In this thesis,taking Manglai mining area in Inner Mongolia as the research background,four amendments（compound microbial fertilizer,lignite cinder,fulvic acid,and water-retaining agent）were used as experimental materials,and L9（34）orthogonal experiment was designed.At the same time,three plants（rye,oat and Elymus pumila）were selected to improve the soil in the mining area,and the plant macro-indexes,soil physical and chemical properties and microbial community diversity were measured and analyzed to explore different plants under each treatment.The results show that:（1）Soil improver can significantly improve the emergence rate,seedling length and root length of plants.Under the synergistic effect of plant and improver,the emergence rate,seedling length and root length can be increased by 28.57%-32.86%,239.49%-260.03%and 59.66%-67.25%,respectively.Based on the experimental conditions,the soil in this study area has the best effect on promoting plant growth under the treatments of No.1（A₁B₁C₁D₁）,No.5（A₃B₁C₃D₂）and No.9（A₃B₃C₂D₁）.Comparing the three plants horizontally,we can know that the interaction effect between soil improver and oat is better,and it can play a better role when adding four improvers at a low level.（2）The soil improvement experiments can effectively increase the soil moisture content,which can be increased from 4.9%to 11.16%,and at the same time significantly improve the structural stability of aggregates,thereby increasing the effect of soil water and fertilizer retention.At the same time,the synergistic effect of plant-amendment can reduce soil p H value and total salt content to different degrees,and the highest growth rates of soil organic matter,alkaline hydrolyzable nitrogen,available phosphorus and available potassium content can reach 339.4%,209.24%,258.79%and 107.838%,and the plant habitat is significantly improved.（3）From the perspective of soil microstructure,after soil improvement,the particles become larger obviously,and many fine particles（organic matter,micro-aggregates,etc.）adhere to the surface of large aggregates,so the soil cohesion is better,among which No.1（A₁B₁C₁D₁）,No.7（A₃B₁C₃D₂）and No.9（A₃B₃C₂D₁）have the most remarkable improvement effects,which shows that these composite measures can effectively enhance the stability of soil aggregates in mining areas and promote large aggregates.（4）Compared with the control experiment,alkaline phosphatase activity,catalase activity and urease activity of plant-amendment increased by 74.26%-234.119%,4.96%-44.6%and 12.4%-168.15%,respectively,and the number of soil microorganisms increased significantly,and the compound microbial fertilizer had a better lifting effect due to the active substances contained in it.At the same time,the bacterial richness and diversity of the improved soil were significantly improved,the bacterial community composition and diversity of the control group soil and the 9groups were significantly different,and the relative abundance of Firmicutes and Bacteroidotal was increased.The thesis has 43 figures,12 tables,and 125 references.