Effect of planting Medicago sativa on microbial communities,enzyme activity and nutrients in mine desert soil
To explore the effectiveness of Medicago sativa(alfalfa)cultivation on the improvement of desert mine soils,the mi-crobial community characteristics,enzyme activities,and nutrient contents of mining desert soils in areas with no alfalfa plant-ing(M0)and those that had been planted for four years(M4)and five years(M5)were analyzed by 16S rRNA high-throughput sequencing,redundancy analysis(RDA),correlation analysis,and other methods.The results showed that:①The Sobs and Chao indices of soil microorganisms in the three groups were ranked as M0<M5<M4,with M5 having the lowest Shannon index and the highest Simpson index.The dominant phyla in the M4 and M5 conditions were Actinobacteria,Proteobacteria,and Chloroflexi,while Actinobacteria and Chloroflexi dominated in M0.② After alfalfa planting,the activities of alkaline phosphatase and urease in the soil increased,while those of catalase and sucrase decreased.The soil contents of alkalinehy-drolyzed nitrogen,available phosphorus,available potassium,and organic matter were ranked as M0<M5<M4.③The abun-dance of both Actinobacteria and Chloroflexi was reduced after alfalfa planting and was negatively correlated with nutrients,whiletheabundance of Proteobacteria increased and was positively correlated with nutrients.The abundance of Acidobacte-ria was increased,together with reduced relative abundance of Bacteroidetes.The abundance of metabolic bacteria involved in heterotrophic and photoautotrophic functions,as well as carbon and nitrogen cycling,was raised.In conclusion,planting alfal-fa can increase the bacterial contents in desert mine soils,together with altering the abundance of the dominant bacterial phyla,enhancing the metabolic functions of the bacteria,thereby effectively improving the soil quality.
万方数据
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