Seasonal variation of soil salinity and its response to groundwater under different land use patterns
The secondary salinization of soil in Karamay Agricultural Development Zone is increasing.In order to explore the correlation between soil salinity and groundwater in the irrigation area and reveal the critical depth of groundwater causing secondary salinization of soil in the irrigation area,this study used classical statistics and geostatistics based on the measured data of total soil salinity,salt ion content and groundwater depth and mineralization in 2023 to study the temporal and spatial variation characteristics of soil salinity and groundwater depth and mineralization in the irrigation area,and analyzed the influence of groundwater on soil salinity.The results showed that the soil salt content in the irrigation area ranged from 1.828 to 4.320 g·kg-1,mainly non-salinized soil and mildly salinized soil.The soil salt content of cultivated land was autumn>spring>summer,and the soil salt content of forest land was spring>autumn>summer.The overall performance of soil salinity is evaporation salt accumulation in spring and autumn,and irrigation in summer to reduce salt.The soil salt anions in the irrigation area are mainly SO42-and Cl-,the cations are mainly K++Na+,and the soil is mainly chloride-sulfate soil.The soil salt ions under different land use patterns changed significantly with the seasons,but the law was not significant.The average groundwater depths in spring,summer and autumn were 3.14,2.67 m and 2.80 m,respectively.The annual average mineralization was 18.25 g·L-1.The spatial distribution characteristics of groundwater depth and soil salinity were basically the same.There is an exponential relationship between soil salinity and groundwater depth,and the correlation coefficient is above 0.622 8.There is no obvious functional relationship between soil salinity and groundwater mineralization.The uplift of groundwater level with high salinity is the main cause of soil secondary salinization in irrigation area.Studies have shown that the regulation of groundwater depth in the irrigation area greater than 2.10 m can effectively improve the problem of secondary salinization of soil.
soil salinizationgroundwaterspatial distributionseasonal changesland use patterns
万方数据
维普
