The Hotan Prefecture of Xinjiang Uygur Autonomous Region,China belongs to arid desert climate,with significant soil salinization issues.The study selected six rivers in Hotan Prefecture(Pishan,Qaraqash,Yurungqash,Cell...The Hotan Prefecture of Xinjiang Uygur Autonomous Region,China belongs to arid desert climate,with significant soil salinization issues.The study selected six rivers in Hotan Prefecture(Pishan,Qaraqash,Yurungqash,Celle,Kriya,and Niya rivers)to explore the spatial distribution of soil salinization in this area and its underlying mechanisms.Sampling was conducted along each river's watershed,from the Gobi in the upper reaches,through the anthropogenic impact area in the middle reaches,to the desert area in the lower reaches.Soil physical-chemical indicators,including total soluble salts,pH,K+,Na+,Ca2+,Mg2+,SO42-,Cl-,CO32-,HCO3-,organic matter,available nitrogen,available phosphorus,and available potassium,were tested,along with the total dissolved solids of surface water and groundwater.The results revealed that the soil water and nutrient contents in anthropogenic impact area were higher than those in Gobi and desert areas,while the pH and total soluble salts were lower than those in Gobi and desert areas.The ions in the soil of the study area were primarily Cl-,SO42-,K+,and Na+,and the ion concentration of soil salt were positively correlated with surface water and groundwater.Overall,the study area exhibited low soil water content,low clay content,infertile soil,and high soil salinization,dominated by weak to moderate chloride-sulfate types.Compared with Gobi and desert areas,the soil in anthropogenic impact area had higher soil water content,lower pH,lower soluble salts,and higher nutrients,indicating that human farming activities help mitigate salinization.These findings have practical implications for guiding the scientific prevention and control of soil salinization in the arid areas and for promoting sustainable agricultural development.展开更多
我国黄土具有明显的区域分布特征,从空间平面上把握其非饱和特性分布规律具有一定的现实意义。以Ⅰ带—兴县、Ⅱ带—富县和Ⅲ带—西安原状黄土为研究对象,测定了黄土不同含水率条件对应的基质吸力,对试验数据拟合得到土水特征曲线变化规...我国黄土具有明显的区域分布特征,从空间平面上把握其非饱和特性分布规律具有一定的现实意义。以Ⅰ带—兴县、Ⅱ带—富县和Ⅲ带—西安原状黄土为研究对象,测定了黄土不同含水率条件对应的基质吸力,对试验数据拟合得到土水特征曲线变化规律,并利用干燥过程的土水特征曲线对一维无限边坡稳定性进行研究。结果表明:兴县、富县、西安原状黄土土水特征曲线在地理空间分布上具有一定的规律性;沿兴县—富县—西安,黄土土样进气值逐渐减小,降湿率呈减小趋势,残余含水率呈增加趋势; Van Genuchten模型对黄土原状土样拟合效果比Gardner方程更好,简化的Van Genu-chten模型对各地区黄土均能较好地拟合;随着深度的增加,边坡稳定性系数逐渐降低,同时随着饱和度的降低,边坡稳定性系数逐渐增加;同时兴县黄土边坡较为稳定,主要是兴县黄土的基质吸力项对抗滑力的贡献要明显大于富县和西安黄土。展开更多
基金This research was supported by the Tianfu Yongxing Laboratory Organized Research Project Funding(2023KJGG05)the Geological Survey Project of Xinjiang Uygur Autonomous Region Geology and Mineral Exploration and Development Bureau(XGMB202356).
文摘The Hotan Prefecture of Xinjiang Uygur Autonomous Region,China belongs to arid desert climate,with significant soil salinization issues.The study selected six rivers in Hotan Prefecture(Pishan,Qaraqash,Yurungqash,Celle,Kriya,and Niya rivers)to explore the spatial distribution of soil salinization in this area and its underlying mechanisms.Sampling was conducted along each river's watershed,from the Gobi in the upper reaches,through the anthropogenic impact area in the middle reaches,to the desert area in the lower reaches.Soil physical-chemical indicators,including total soluble salts,pH,K+,Na+,Ca2+,Mg2+,SO42-,Cl-,CO32-,HCO3-,organic matter,available nitrogen,available phosphorus,and available potassium,were tested,along with the total dissolved solids of surface water and groundwater.The results revealed that the soil water and nutrient contents in anthropogenic impact area were higher than those in Gobi and desert areas,while the pH and total soluble salts were lower than those in Gobi and desert areas.The ions in the soil of the study area were primarily Cl-,SO42-,K+,and Na+,and the ion concentration of soil salt were positively correlated with surface water and groundwater.Overall,the study area exhibited low soil water content,low clay content,infertile soil,and high soil salinization,dominated by weak to moderate chloride-sulfate types.Compared with Gobi and desert areas,the soil in anthropogenic impact area had higher soil water content,lower pH,lower soluble salts,and higher nutrients,indicating that human farming activities help mitigate salinization.These findings have practical implications for guiding the scientific prevention and control of soil salinization in the arid areas and for promoting sustainable agricultural development.
文摘我国黄土具有明显的区域分布特征,从空间平面上把握其非饱和特性分布规律具有一定的现实意义。以Ⅰ带—兴县、Ⅱ带—富县和Ⅲ带—西安原状黄土为研究对象,测定了黄土不同含水率条件对应的基质吸力,对试验数据拟合得到土水特征曲线变化规律,并利用干燥过程的土水特征曲线对一维无限边坡稳定性进行研究。结果表明:兴县、富县、西安原状黄土土水特征曲线在地理空间分布上具有一定的规律性;沿兴县—富县—西安,黄土土样进气值逐渐减小,降湿率呈减小趋势,残余含水率呈增加趋势; Van Genuchten模型对黄土原状土样拟合效果比Gardner方程更好,简化的Van Genu-chten模型对各地区黄土均能较好地拟合;随着深度的增加,边坡稳定性系数逐渐降低,同时随着饱和度的降低,边坡稳定性系数逐渐增加;同时兴县黄土边坡较为稳定,主要是兴县黄土的基质吸力项对抗滑力的贡献要明显大于富县和西安黄土。
