Comparison On Soil Microbial Nutrient Utilization Strategies Between Cultivation Of Vicia Villosa And Avena Sativa

Leguminous and gramineous plants are important forage species,as green manure plants,they are widely used in the management of agronomic measures such as soil fertilization and crop rotation.Due to the difference in nutrient absorption and utilization of Leguminous and gramineous plants,it is bound to cause changes in the carbon,nitrogen,and phosphorus content of soil resources and their stoichiometric characteristics.However,in this case,it is unclear how soil microorganisms adjust their nutrient utilization strategies.In this study,we choose two kinds of green manure plants Vicia villosa(leguminous plants)and Avena sativa(gramineous plants)as experiment material,which are widely planted in the Loess Plateau region.Based on the principle of ecological stoichiometry,from the relationship of nutrient(carbon nitrogen and phosphorus)balance between organisms and the environment,we studied the characteristics of the effects of these two plants cultivations on soil resources and microbial carbon,nitrogen and phosphorus nutrients content and stoichiometric,as well as the regulation process of soil microorganisms extracellular enzymes production,nutrient utilization and microbial community structure.The main results were displayed as following:(1)The total C:N ratio of nutrient accumulation in Vicia villosa was significantly lower than that of Avena sativa,and the total N:P ratio was significantly higher than that of Avena sativa,,but there was no significant difference between the two plants.(2)Vicia villosa and Avena sativa cultivation have no significant effect on soil total nitrogen and phosphorus content,but the cultivation of these two plants significantly changed the content of soil dissolved organic carbon,total dissolved nitrogen and soil dissolved organic phosphorus,as well as soil microbial biomass carbon,microbial biomass nitrogen and microbial biomass phosphorus concentration,resulting in a significant increase in the soil C:N imbalance coefficient of Vicia villosa cultivation compared with the control treatment,the soil C:N imbalance coefficient of Avena sativa cultivation was not significantly different from that of the control treatment,and the effects of planting two plants on soil C:P imbalance coefficient and N:P imbalance coefficient were not significantly different from the control treatment.(3)Vicia villosa and Avena sativa cultivation significantly altered soil microbial C-,N-and P-acquisition enzymes and their stoichiometry,resulting in Vicia villosa and Avena sativa cultivation soil microbial C-and N-acquisition enzymes ratios and C-and P-acquisition enzymes ratios were significantly lower than the control treatment.In addition,the ratio of C-and N-acquisition enzymes in the soil of Avena sativa cultivation was significantly lower than that in Vicia villosa,but there was no significant difference in the ratio of C-and P-acquisition enzymes between the two plants.The ratio of N-and P-acquisition enzymes in Vicia villosa cultivation soil was significantly lower than that in control treatment and Avena sativa cultivation soil,and there was no significant difference in the ratio of C-and P-acquisition enzymes in Avena sativa cultivation soil compared with control treatment.(4)Vicia villosa and Avena sativa cultivation significantly changed the soil microbial carbon use efficiency.The soil microbial carbon use efficiency of Avena sativa cultivation soil was significantly higher than the control treatment and Vicia villosa cultivation soil,and the soil microbial carbon use efficiency of Vicia villosa cultivation soil was not significantly different from the control treatment.The soil microbial community C:N has no homeostasis,while the soil microbial community showed a strong C:P and N:P homeostasis.(5)Vicia villosa and Avena sativa cultivation significantly altered the soil microbial community structure.Compared with the control treatment,the absolute abundance of fungi and bacteria in the Avena sativa cultivation soil was significantly increased,and the absolute abundance of fungi in the Avena sativa cultivation soil was significantly higher than that in the Vicia villosa cultivation soil,while the absolute abundance of bacteria was not significantly different between these two plants.The ratio of soil fungi and bacteria(F/B)in the soil of Vicia villosa and Avena sativa cultivation was not significantly different from that of the control treatment,and there were no significant difference between these two plants.There was no significant difference in the bacterial community diversity between Vicia villosa cultivation soil and Avena sativa cultivation soil,but both of them were significantly lower than control,the fungal diversity of Vicia villosa cultivation soil was significantly lower than that of Avena sativa cultivation soil.