Distribution Characteristics of Soil Physicochemical Properties and Salt Ions in Typical Oasis Irrigation Areas of Xinjiang
Soil salinization and arable land degradation have seriously restricted the sustainable development of oasis irrigation agriculture in Xinjiang.Exploring the distribution characteristics of soil physicochemical properties and salt ions is a prerequisite and foundation for saline-alkaline land improvement and comprehensive utilization as well as high-quality development of oasis agriculture.The distribution characteristics of nutrient contents,and salt content and its ions in the 0～500 cm soil profile were quantitatively analyzed in the Manas River Irrigation Area in northern Xinjiang,and in the Aksu River Irrigation Area and Kashgar River Irrigation Area(Aksu-Kashgar River Irrigation Area)in southern Xinjiang.The results showed that the contents of soil organic matter,alkali-hydrolysable nitrogen,available phosphorus,available potassium,and total nitrogen in the study areas all showed a gradually decreasing trend with the increase of soil depth.In the Manas River Irrigation Area,the average values of soil organic matter,alkaline dissolved nitrogen,available phosphorus,total nitrogen content and pH value were higher in the 0～30 cm and 0～100 cm soil layers,but the average values of organic matter,alkaline dissolved nitrogen,available potassium and total nitrogen content in the 100～500 cm soil layer were lower in the Manas River Irrigation Area.The average values of total salinity and electrical conductivity in the 0～30 cm soil layer were 21.14%and 8.53%higher in the Aksu-Kashgar River Irrigation Area,but the average values of total salinity and electrical conductivity in the 60～100 cm soil layer were 17.55%and 16.50%lower in the Aksu-Kashgar River Irrigation Area,respectively.In the study areas,the dominant cations were Na+and Ca2+,while the dominant anions were SO2-4 and Cl-.In the Manas River Irrigation Area,Na+was the highest salt ions,while SO2-4 was the highest in the Aksu-Kashgar River Irrigation Areas.In the Manas River Irrigation Area,53.85%of the 0～30 cm soil layer was classified as saline soil,50.00%of the 30～60 cm soil layer was classified as moderately and severely saline soils,and 25.00%of the 60～100 cm soil layer was classified as severely saline soil.The dominant saline soil was sulfate,followed by chloride-sulfate.In the Aksu-Kashgar River Irrigation Area,78.26%of the 0～30 cm soil layer was classified as saline soil,with the highest proportion being severely saline soil.Additionally,60.86%of the 30～60 cm layer was classified as mildly or severely saline soils,and 39.13%of the 60～100 cm soil layer was classified as non-saline soil.The dominant saline soils were chloride-sulfate,followed by sulfate.The results can provide a scientific foundation for the comprehensive utilization of saline-alkaline land and precise fertilization in the oasis irrigation area of Xinjiang.
国家科技期刊平台
NSTL
万方数据
