Ecological Stoichiometry Characteristics Of Soil Carbon,Nitrogen And Phosphorus In Cultivated Land Of Yili Prefecture,Xinjiang

As the carrier of many ecological processes,soil is an important place for the exchange of energy and matter in the ecosystem.As the key elements of the terrestrial ecosystem,soil carbon,nitrogen and phosphorus directly affect the physiological metabolism,growth and development of plants.These elements are based primarily on studying the changes of nutrient structure,nutrient cycling and soil productivity under different influencing factors in farmland ecosystem.Xinjiang Yili prefecture is an important base of grain production.To understand the spatial distribution of C,N,P ecological stoichiometry and its influencing factors of cultivated soil in Yili prefecture is of great practical significance for the scientific management of cultivated soil nutrients in Yili Prefecture.This study takes Yili Prefecture of Xinjiang Uygur Autonomous Region as the research area.In this study,1036 soil samples collected in 2020 were used as research data.The spatial distribution characteristics and influencing factors of C,N,P and their ecological stoichiometry of cultivated soil in Yili Prefecture were studied by geostatistics and classical statistical method.The main results are as follows:(1)Soil organic carbon,total nitrogen,total phosphorus,C/P and N/P showed moderate variation,while C/N showed weak variation.This indicates that all indicators except C/N in the study area show strong spatial variability,and C/N is evenly distributed in space.The order of soil nutrient index and their stoichiometric ratios was organic carbon > total nitrogen >C/P >N/P > total phosphorus >C/N.(2)Soil C,N,P and their stoichiometric ratios showed strong spatial correlation in Yili,and the lump-to-gold ratios of all indexes were less than 25%.The best fitting model of semivariance function of soil organic carbon,total nitrogen,C/P and N/P was Gaussian model,and the best fitting model of total phosphorus and C/N was spherical model.Three spatial interpolation methods,namely ordinary Kriging method,inverse distance weight method and radial basis function method,are cross-verified to determine the interpolation accuracy of three different interpolation methods.It was found that the ordinary Kriging method was the best interpolation method for soil organic carbon,total nitrogen,C/P and N/P,and the radial basis function method was the best interpolation method for soil total phosphorus and C/N.(3)The spatial distribution trend of soil organic carbon and total nitrogen contents was high in the south and low in the north,but high in the east and low in the west.Soil total phosphorus content is higher in the Midwest,east and southwest,but lower in the north,west and eastcentral regions.The distribution of soil C/N was patchy.The spatial distribution trend of soil C/P and N/P was basically consistent,and the spatial distribution of soil C/P and N/P was higher in the southwest and east,and lower in the north,west and central.(4)There were significant differences in soil organic carbon,total nitrogen,C/N,C/P and N/P under different soil types,soil parent materials and farmland use type in Yili Prefecture(P<0.05).There were significant differences in soil total P among different soil types(P<0.05),but no significant differences under different soil parent materials and farmland use type.