关键词: 土壤养分, 土壤盐分, 空间变异, 地统计学, 酒泉市, 盐碱土壤

Abstract: In order to study the correlation between soil nutrients and salinity contents in saline-alkali farmland,spatial autocorrelation,semi-variogram and Kriging interpolation methods were used to analyze the organic matter,alkaline nitrogen,available phosphorus,available potassium,and salinity contents of saline-alkali arable land of Jiuquan City,and the spatial variability of their contents and its influencing factors were analyzed. The results showed that,the average contents of soil alkaline nitrogen,available phosphorus,available potassium were 64.30,15.50,121.40 mg/kg respectively,and organic matter and salt contents were 12.80, 7.49 g/kg, respectively.The spatial variation coefficients of nutrient and salinity contents were both moderate variation. Spatial variability analysis found that the nugget coefficients of the five soil factors in the study area were all less than 0.25,which indicated that they were mainly affected by structural factors such as terrain,parent material and vegetation coverage.The contents of organic matter,alkaline nitrogen,and available potassium in saline-alkali arable soil were higher in south of the study area than those in the north,while the available phosphorus and salinity contents alternated from east to west in high and low cycles.The correlation analysis showed that the contents of organic matter,alkaline-hydrolyzed nitrogen and salinity in saline soil were extremely significantly negatively correlated(P<0.01),but the content of available phosphorus was significantly positively correlated with salinity content(P<0.05).This indicates that soil nutrient content affects soil salinity content to a certain extent.

Key words: Soil nutrient, Soil salinity, Spatial variability, Geostatistics, Jiuquan City, Saline-alkali soil