塔里木盆地西南缘典型灌区土壤盐渍化特征分析——以塔吉克阿巴提镇为例

Characteristics of Soil Salinization in Southwestern Tarim Basin-A Case Study in Irrigation Area of Tajik Abat Town

在野外GPS定点定位调查、土壤样品分析的基础上,借助Excel和ArcGIS 9.3等软件,对新疆自治区喀什市岳普湖县塔吉克阿巴提镇0—30cm土层的盐离子特征、灌区土壤盐渍化现状及空间分布特征进行了分析。结果表明,0—30cm土层土壤中的离子以Cl-,SO2-4,Na+,Ca2+为主;Na+与Cl-呈极显著正相关关系,相关系数为0.98,HCO-3与其它6种离子(Na+,Ca2+,Mg2+,K+,Cl-,SO2-4)呈负相关关系;受灌排系统影响较大的农田0—30cm土壤中Cl-/SO2-4比值远小于不受灌排系统影响的荒地;农田和荒地0—30cm土壤中的Cl-/SO2-4比值与总盐呈正相关关系,相关系数依次为0.68和0.32。现阶段对塔吉克阿巴提镇灌区农业危害最严重的是氯化物—硫酸盐盐渍化土,硫酸盐盐渍化土表现为盐渍化土地向非盐渍化土地转变的过渡类型;非盐渍化农田及轻度盐渍化农田主要分布在开垦较早,灌排系统畅通的区域,灌排系统不畅通的区域仍然处于脱盐缓慢或持续积盐的状态。

On the basis of field survey, GPS location and soil analysis, a study was carried out with the Excel and ArcGIS 9.3 software to analyze salt ions, present situation and spatial characteristics of soil salinization at the Tajik Abat Town. The results showed that ions in 0--30 cm soil were dominated by Na＋ , Ca2＋ , Cl- , SO24-, among which there was a strong positive correlation（r=0.98） between Na＋ and Cl-, negative corre- lations between HCO3- and the other six ions（Na＋ , Ca2＋ , Mg2＋ , K＋ , Cl-, SO24- ） ; the ratio of Cl- to SO24- was much lower on cultivated land than wasteland; the ratio of Cl to SO24- in 0 30 cm soil was positively correlated with total salt on both cultivated land and wasteland with correlation coefficients 0.68 and 0.32, respectively. At the present stage, chloride-sulfate salinization soil（the latter is a transitional type between salinization and non-salinization soil） is the most harmful factors for irrigated agriculture at the Tajik Abat Town. Non-salinization soil and less salinization soil are mainly distributed in the area with early cultivated land with better irrigation and drainage systems while slow leaching process or continueing salinity accumula- tion process still take places in the area with bad irrigation and drainage systems.