莫索湾灌区土壤剖面盐分的季节性变化特征

以新疆莫索湾灌区为研究区域，通过对该地区春季和秋季土壤剖面取样，得到土壤盐分值并采用Arc-gis 10.0软件对土壤盐分进行地统计学分析，从而探索莫索湾灌区不同季节土壤剖面盐分的空间变化特征。结果表明：研究区土壤剖面盐分含量随土层深度的增加而升高，属于底聚型；盐分含量总体表现为东南部高于西北部，2014春季高于2013年秋季，是因为灌区春季温度高于秋季，且积雪融化造成部分地区地下水位升高，强烈的地表蒸发使得底层盐分上移到耕层。不同季节各层土壤盐分含量值都符合对数正态分布，变异系数在66％~92％之间，具有中等强度的空间变异性，表层土壤变异大于底层；半方差分析得出2013年秋季和2014年春季各土层土壤盐分含量可以用高斯模型、指数模型和线性模型拟合，拟合模型的R2均大于0.75；土壤盐分含量的块金系数 C0/( C0＋ C )值在31％~42％之间，盐分含量值均表现为中等强度的空间自相关，0~100 cm土壤盐分受自然因素和人为因素共同作用。研究结果可为莫索湾灌区盐渍化土壤的分区、改良和利用提供理论基础。

Spatial variability of soil salinity in different seasons in Mosuowan irrigation area

The spatial variation of soil salinity in different seasons in Mosuowan irrigation area of Xinjiang was explored by soil sampling in both spring and autumn, and soil salinity was obtained by conductivity analysis, Arcgis 10. 0 software was used for Geostatistical analysis. The results showed that, salt content of the soil profile of the soil layers increased with soil depth, the performance was of the bottom coalescence. The salt content in the southeast of study area was higher than that of the north-west, and it was higher in the spring of 2014 than the autumn of 2013. This was because the temperature was higher in spring than autumn. Groundwater levels in some areas rose by snow melt, making a strong evaporation of salt on the bottom to the top-soil. Salt content values in different seasons consisted with a lognormal distribution, and coefficients of variation were between 66% ~92%, with moderate spatial variability. Variation in topsoil was greater than the that of deeper layers. Half-way analy-sis of soil salt content variance results in 2013 and 2014 in the spring and autumn were simulated by Gaussian model, the expo-nential model and linear model fitting. Soil salt content of C0/( C0 + C) values were between 31% ~42%. Salt content value showed moderate spatial autocorrelation, 0~100 cm soil salt was affected by both natural factors and human factors. The re-sults provided a theoretical basis for soil salinization, improvement and utilization in the Mosuowan irrigationarea.