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在塔里木河上游农业绿洲区选取草地、裸地、棉花地和盐碱地4种典型地表特征,用圆盘入渗仪测定土壤水分入渗过程并做模型拟合与分析.结果表明:绿洲内不同地表特征下土壤水分入渗性能存在明显差异,稳定入渗率大小为棉花地(1.02mm.min-1)>草地(0.76mm.min-1)>裸地(0.36mm.min-1)>盐碱地(0.11mm.min-1);在入渗初期,累计入渗量为盐碱地最大,草地和棉花地次之,裸地最小,但随入渗时间增长累计入渗量逐步受控于稳定入渗率.以裸地为参照,棉花地和草地的入渗性能较好,而盐碱地入渗性能较差.应用常用的入渗模型对入渗过程进行了模拟:Kostiakov模型和Horton模型分别对棉花地、草地和裸地、盐碱地均具有最好的模拟效果,这两种模型在本区内有最好的适用性和准确性;Green-Ampt模型在本区的适用性较差.
Four representative surface features of grassland, bare land, cotton land and saline land were selected in the agricultural oasis area in the upper reaches of the Tarim River. The soil infiltration process was determined by disk infiltration meter and the model was fitted and analyzed.The results showed that: Soil moisture infiltration characteristics were significantly different, with stable infiltration rates of 1.02 mm.min-1> 0.76 mm.min-1> 0.36 mm.min-1> (0.11mm.min-1) .In infiltration stage, the cumulative infiltration was the largest in saline-alkali soil, followed by grassland and cotton, and the bare soil was the smallest. However, with the infiltration time increasing, the cumulative infiltration was gradually controlled by the steady infiltration Rate.With the bare land as reference, the infiltration properties of cotton land and grassland were better, while the infiltration performance of saline land was poor.The infiltration process was simulated by common infiltration model.The Kostiakov model and Horton model were used to analyze cotton infiltration , Grassland and bare land, and saline-alkali land all have the best simulation results. The two models have the best applicability and accuracy in this region. The Green-Ampt model is less suitable in this region.