干旱-半干旱区不同地质背景区典型灌区土壤盐分特征及成因对比分析  

Soil Salinity Characterization and Causes in Irrigation Areas with Different Geological Backgrounds in Arid and Semi-Arid Regions

作　　者：王昊 张生银 张顺存 黄翠华 廖杰 WANG Hao;ZHANG Shengyin;ZHANG Shuncunn;HUANG Cuihua;LIAO Jie(Drylands Salinization Research Station,Northwest Institute of Eco-Environment and Resources,Chinese Academy of Sciences,Lanzhou 730000,China;Gansu Salinization Observation and Research Station,Lanzhou 730000,China;University of Chinese Academy of Sciences,Beijing 100049,China)

机构地区：[1]中国科学院西北生态环境资源研究院干旱区盐渍化研究站,兰州730000 [2]甘肃省盐渍化野外科学观测研究站,北京100049 [3]中国科学院大学,兰州730000

出　　处：《地球与环境》2023年第6期620-632,共13页Earth and Environment

基　　金：第二次青藏高原综合科学考察研究资助(2019QZKK0305);宁夏回族自治区重点研发计划项目(2020BBF02003)。

摘　　要：为揭示干旱-半干旱区盐碱土盐化与碱化的差异性演化过程,本研究结合地质学对景泰灌区、河套灌区盐碱土进行系统采样分析,采用主成分分析以及水-岩反应模拟实验对两灌区土壤盐碱化特征及成因开展对比研究。结果表明:景泰灌区土壤盐分离子主要为Na^(+)、Cl^(-)、SO_(4)^(2-),河套灌区Na^(+)、Cl^(-)、SO_(4)^(2-)相对较低,CO_(3)^(2-)含量较高;景泰灌区土壤盐化过程主要与周边地层的三叠纪红砂岩及奥陶纪海相硅质岩的可溶盐淋溶有关,河套灌区土壤碱化过程主要受到狼山、阴山太古代片麻岩群及元古代花岗岩群化学风化影响。可见土壤盐化(EC)与碱化(pH)是不同因素的盐渍化过程,区域地层母岩及其风化机制的不同是干旱-半干旱区土壤盐化和碱化差异性成因的根源。To differentiate the influence of salinization and alkalinization on soil formation in arid and semi-arid regions, principal component analysis and water-rock reaction simulation experiments were used in combination with the geological background information to compare the characteristics and causes of soil salinization in the Jingtai and Hetao irrigation areas. The results show Na^(+), Cl^(-) and SO_(4)^(2-) as the dominate ions found in the soils of the Jingtai irrigation area. In comparison, the soil contents of Na^(+), Cl^(-) and SO_(4)^(2-) of the Hetao irrigation area were relatively low, whereas the CO_(3)^(2-) content was high. Soil salinization in the Jingtai irrigation area is mainly associated with soluble salt leaching from Triassic red sandstone and Ordovician Marine siliceous rocks of the surrounding strata, whereas soil alkalinization in the Hetao irrigation area were mainly affected by the chemical weathering of the Archaean gneiss group and Proterozoic granite group in Langshan and Yinshan. Accordingly, soil salinization(EC) and alkalinization(pH) can be regarded as salinization processes induced by different environmental factors. Stratigraphic bedrocks and weathering mechanisms are responsible for the differences in soil salinization and alkalinization in arid and semi-arid areas.

关 键 词：盐碱土盐分特征 成因对比 水-岩反应 景泰灌区 河套灌区 

分 类 号：P66[天文地球—地质学]