新疆伊犁河灌区土壤地球化学特征研究

Study on the geochemical characteristic features of the soil in Ili River irrigation area,Xinjiang

根据2009年伊犁河灌区土壤监测和取样分析资料,运用半方差函数与克里格插值法,对伊犁河灌区土壤盐分和主要离子组成特征与空间分布情况进行研究。结果表明,研究区0~3 cm土层含盐量约占0~60 cm土层含盐量的60.19%,土壤盐分剖面分布呈现表聚性。土壤各层盐分质量比与主要离子质量比呈现强烈的空间变异性。表层土壤主要离子总体上在东西向和南北向上呈二阶趋势效应。从克里格插值结果可以看出,研究区表层土壤离子组成的空间分布格局基本相似,即各离子质量比最高值均出现在研究区的中、西部区域,并形成了区域土壤的积盐中心。

The paper intends to make a study on the geochemical characteristic features of the soil in Ili River irrigation area,Xinjiang. As is known,soil salinization is one of the most troublesome eco-environmental problems in the arid,semi-arid land,which tends to affect the regional grain production safety and the sustainable use of land resources. According to the monitoring and sample analysis of the soil in Ili River irrigated area,this paper intends to analyze the characteristic features and the spatiotemporal variation of the soil in Ili River irrigated area by using the semi-variogram and Kriging. The results of our study prove that： the salinity of the surface soil layer account for 60. 19% of the total salinity of 0-60 cm soil layer. Such soil salinity is mainly scattering at the top soil surface. Moreover,we have also made clear that the salinity and the main ion component of the soil turn to be strong in spatial variation. And the main ion component of the surface soil shows a feature of U-shaped distribution in the east-west and north-south direction. Gaussian model can be taken as the theoretical model of the variation function curve for K＋,Mg2 ＋,Cl-,CO2-3,that accounts for the main soil geo-features,the exponential model for Na＋and spherical model may account for the components of SO2-4,Ca2 ＋and HCO-3. The results of Kriging interpolation prove that the spatial distribution of each ion component of the surface soil in the area under study turns to be very much similar for the higher concentration of ion components of the surface soil in the central and western parts of the area,thus forming the great salinity concentration center of the soil in the area. It can also be concluded that it is very helpful to apply Kriging method to detect the problematic areas as a wonderful tool for soil resource management.