【摘要】 土壤盐分的动态分析与监测,是实现盐渍化土地科学管理与利用的必要前提。运用GIS技术,结合地统计学方法,分析了渭干河绿洲土壤盐渍化的分布格局,探讨了不同土地利用类型下土壤盐分的变化规律。结果表明:土壤盐分离子含量随土层深度增加而减少,CO₃^2-和HCO₃^-变化不明显,整个剖面表现为:Na⁺+K⁺>Ca²⁺>Mg²⁺,SO₄^2->Cl^->HCO₃^->CO₃^2-,具有中-强变异性,除了HCO₃^-、CO₃^2-和Ca²⁺外,其他盐分离子变异系数随深度增加而减小。不同土地利用类型的土壤含盐量具有显著差异垂向分布,耕地、荒地和草地、林地分别呈现为平均型、表聚型和底聚型盐分剖面,且各类型表层土壤（0～40 cm）含盐量依次为荒地(38.42 g·kg^-1)>草地(16.30 g·kg^-1)>耕地(5.37 g·kg^-1)>林地(4.62 g·kg^-1)。渭干河绿洲土壤属于重盐土类型,自然因素（蒸降比和地下水波动等）是土壤盐渍化的形成条件,而人为干扰（土地利用方式、灌排、施肥等）则促进了土壤盐渍化的发展。更多还原

【Abstract】 Soil salinization is one of the important factors impacting the stability of oasis and sustainable agriculture. The dynamic monitoring and analysis of soil salinity are the prerequisite to manage and utilize the salinized land scientifically. This study aims to investigate the spatial variation and driving mechanism of soil salinization under the action ofclimate change and human activities in the Weigan River Oasis,Xinjiang,China. In October 2012,based on the soil type map and the land use type mapof the Weigan River Oasis,we collected 35 soil profiles covering four land use types（ i. e. cultivated land,forest,grassland,and saline-alkali land） using GPS positioning technology. Based on the GIS technology and Geostatistics methods,this study analyzed the distribution of soil salinization and the soil salinity variation under different land use types. The results indicated that the soil salt ion content in general is decreased as the soil gets deeper with CO₃^2- and HCO₃^- being exceptional and the values of soil salt ions were listed in a descending order as follows: Na⁺+ K+> Ca²⁺> Mg²⁺,SO₄^2--> Cl> HCO₃^-> CO₃^2- for all the soil profiles. Generally,the variation coefficient of soil salt ion content was sitting in the range between 25% and 200%,indicating that the soil salinity in the region had a moderate to strong variability. The vertical distributions of soil salinity presented a significant difference for different land use types. For the cultivated land type,its soil salinity was a constant at different depth of the soil. For the grassland and saline-alkali land（ wasteland）,their soil salinity was accumulated in topsoil while for the forest,the soil salinity was accumulated at the bottom. In addition,the salinities in the surface soil（ 0-40 cm） for the four typical land use types were listed in an descending order as follows: wasteland( 38. 42 g·kg^-1) > grassland( 16. 30 g·kg^-1) > cultivated land( 5. 37 g·kg^-1) > forest 4. 62( g·kg^-1). Overall,the soil in the Weigan River Oasis is heavily salinized,which was caused by the combination of nature and human factors. On the one hand,the natural factors including the ratio of evaporation to rainfall and groundwater fluctuationare the forming conditions of soil salinization. On the other hand,human disturbances,such as land use,irrigation,and fertilization,aggravate the soil salinization. In order to improve the deteriorating ecological environment and soil salinization to ensure asustainable oasis agriculture,we should strictly control the scale of reclamation,improve the construction of water conservancy,and strengthen water-saving irrigation agriculture in the process of land exploitation and utilization in the Weigan River Oasis. Furthermore,rational exploitation of the groundwater resources in alleviating the shortage of surface water resources is also needed to solve the problem of uncoordinated irrigation and drainage to avoid secondary salinization.更多还原