The Spatial Geostatistical Distribution Characteristics Of Soil Nutrients In Hequ Dam Land Of Shanxi Province

As a result of the interaction of natural and human factors,soil nutrients in the dam land have certain spatial variability in different geographical soil layers,thus showing a specific spatial structure.Dam land is a powerful guarantee for food security and dynamic balance of cultivated land in China.The construction of dam soil can effectively control regional soil and water loss,reduce flood disasters in the downstream area,and improve crop yield.As a result of the interaction of natural and human factors,soil nutrients in the dam land have certain spatial variability in different geographical soil layers,thus showing a specific spatial structure.Dam land is a powerful guarantee for food security and dynamic balance of cultivated land in China.The construction of dam soil can effectively control regional soil and water loss,reduce flood disasters in the downstream area,and improve crop yield.It is of great significance for rational planting and scientific fertilization to analyze the spatial characteristics of soil nutrients in dam land.In this paper,the spatial variability of total nitrogen,total phosphorus and total potassium in soil organic matter and large amounts of elements in 0-20cm and 20-40cm soil layers was studied by means of GPS positioning technique and classical statistical methods.The results of traditional analysis showed that the soil organic matter and total nitrogen,total phosphorus and total potassium in Shuerliang small watershed,Hequ County,Shanxi Province,had varying degrees of variation in 0-20cm and 20-40cm soil layers.The variation coefficients of soil total phosphorus and potassium were all small,about 6%-7%,and the variation coefficients of total phosphorus and potassium were the smallest(6.92%).The coefficient of variation of organic matter and total nitrogen was 28.64%.The coefficient of variation of total phosphorus and total potassium was less than 10%.The coefficient of variation of total phosphorus and total potassium was the smallest(4.01%).The semi-variance function of soil properties and nutrients was analyzed by GS+9.0 software,and the characteristic parameters of the semi-variance function were obtained.According to the semi-variance function model,the two-dimensional spatial distribution maps of four nutrients in 0-20cm and 20-40cm soil layers were plotted respectively.The results showed that the organic matter and total nitrogen content in 0-40cm soil layers were higher than those in 0-40cm soil layers.The content of organic matter,total nitrogen,total phosphorus and total potassium in the two soil layers conformed to the Gauss model,and the lump gold effect was less than 1%.It had a strong spatial correlation.The contents of the four soil nutrients in the two soil layers were not uniform and few.In this paper,traditional statistics,geostatistics,GPS and GS+9.0 software were used to analyze the nutrient elements in the dam soil of Shuerliang small watershed in Hequ County,Shanxi Province.The spatial distribution map of soil nutrients in the dam soil of Shuerliang small watershed in Hequ County was obtained by GS+9.0 software technology,which is helpful for balanced fertilization,scientific management and improvement of dam.The potential productivity of land is of great significance.