不同盐碱斑覆盖度下草地土壤盐分及磷有效性分析  

Analysis of Soil Salinity and Phosphorous Availability of Grassland under Different Saline Spot Coverage

作　　者：陈晓鹏 王一昊 李锦扬 李锐[1] 赵祥[1] 董宽虎[1] CHEN Xiaopeng;WANG Yihao;LI Jinyang;LI Rui;ZHAO Xiang;DONG Kuanhu(College of Grassland Science,Shanxi Agricultural University,Taigu 030801,China)

机构地区：[1]山西农业大学草业学院,山西太谷030801

出　　处：《山西农业科学》2020年第9期1481-1486,共6页Journal of Shanxi Agricultural Sciences

基　　金：国家自然科学基金项目(31800402);山西省优秀博士来晋工作奖励资金科研项目(SXYBKY201806)。

摘　　要：为探究盐碱化草地地表盐碱斑覆盖度的决定因素及其对土壤有效磷的影响,对5个地表盐碱斑覆盖度下晋北盐碱化草地土壤pH、盐分及磷有效性进行分析,并使用结构方程模型模拟土壤盐分及磷有效性对盐碱斑覆盖度变化的响应路径。结果表明,该区草地土壤pH值>8.5,0~40 cm土壤含盐量为1.44~3.90 g/kg,土壤盐渍化程度较低,植物生长主要受碱害影响;随盐碱斑覆盖度增加,土壤含盐量逐渐升高,但有效磷含量逐渐降低;盐碱斑覆盖度>5%的土壤pH值显著高于无盐碱斑覆盖的草地,但随盐碱斑覆盖度增加,土壤pH无明显变化趋势。逐步线性回归分析结果表明,Na+和HCO3-是影响土壤pH的主要离子,Na+、SO42-和HCO3-含量主导土壤含盐量变异;路径分析结果表明,土壤磷有效性主要受土壤pH影响,与含盐量及其引起的盐碱斑覆盖度变化无直接关联。To explore the determinants of the coverage of salinity spots on the saline-alkali grassland and their effects on soil available phosphorus,the soil pH,salinity and phosphorus availability of a saline-alkaline grassland in northern Shanxi were analyzed under five salinity spots coverage,and the structural equation model was used to simulate the path of the salinity and phosphorus availability responding to changes of salinity spots coverage.The result showed that the grassland soil in this area had a pH of more than 8.5,and the salt content at 0-40 cm depth was 1.44-3.90 g/kg,the soil was slightly salinized and plant growth was probably affected by high soil pH.As the salinity spots coverage increase,soil salinity gradually increased,but the content of available phosphorus gradually decreased.The soil pH of 5%-20%of salinity spots coverage was significantly higher than grassland without saline spots,while the soil pH was no obvious change trend from 5%to 20%coverage.The stepwise linear regression analysis result showed that Na+and HCO3-were the main ions affecting soil pH,and the content of Na+,SO42-and HCO3-dominated the variation of soil salt content.Path analysis results showed that soil available phosphorus content was mainly affected by the soil pH,and had no direct relationship with soil salinity and the resulting changes of salinity spots coverage.

关 键 词：盐碱斑 盐渍化 有效磷 盐碱化草地 

分 类 号：S153[农业科学—土壤学]