基于WET的红寺堡灌区土壤盐渍化分布特征研究

宁夏中北部黄河灌区的土壤盐渍化问题已经成为影响宁夏农业生产的重要问题之一,红寺堡灌区是宁夏扶贫扬黄灌溉工程重点开发的新灌区,土壤盐渍化问题尤为严重,急需治理改良。本文分析了潜水位埋深、地质、水文地质条件等与土壤盐渍化的关系;同时,在宁夏首次应用WET土壤水分温度电导率速测仪(以下简称WET)测试了灌区土壤的电导率等参数,对土壤盐渍化进行了评价。结果表明:在红寺堡灌区,潜水埋深自北向南逐渐增大,TDS浓度自北向南逐渐减小,全盐量的变化也是由北向南逐渐减小。地下水位埋深浅,地下水TDS值高的区域土壤盐渍化严重。在红寺堡镇、海子塘、甜水河脑及上游地段土壤全盐量达到了区内最大值,这些地区土壤盐渍化严重,其中甜水河脑及上游地段属于重盐渍化区。

Study on distribution characteristics of soil salinization in Hongsibu irrigation area based on WET

Soil salinization has become one of the most serious problems that affect the development of agricultural production in Yellow River irrigation areas of the central north Ningxia. As a key development of new irrigated area in irrigation project of Ningxia Hui Autonomous Region, soil salinization problem in Hongsibu has become an important issue that need for urgent improvement. The paper correctly analyzed the relationship of soil salinization with groundwater depth, geology and hydrology. Meanwhile, the WET soil moisture meter (hereinafter referred to as WET) was first applied to test ECp(pore water conductivity) in Hongsibu irrigated area, and evaluate soil salinization distributing characteristics. The results show that in Hongsibu, groundwater depth gradually becomes deeper from north to south, TDS concentration gradually decrease from north to south, and the salinity gradually reduces from north to south. Soil salinization is much more serious in lower groundwater depth and high TDS areas. This theory can be verified in Hongsibu Town, Haizi tang and the source and upper reaches of Tianshui River, where the salinity reaches the maximum and soil salinization is serious, and the source and upper reaches of Tianshui River belongs to heavily salinized area.