| 引用本文: | 李争争,屈忠义,杨 威,等.暗管排水对鄂尔多斯地区重度盐碱地盐分迁移规律的影响[J].灌溉排水学报,2021,(7):122-129. |
| LI Zhengzheng,QU Zhongyi,YANG Wei,et al.暗管排水对鄂尔多斯地区重度盐碱地盐分迁移规律的影响[J].灌溉排水学报,2021,(7):122-129. |
|
| 摘要: |
| 【目的】探究暗管排水对鄂尔多斯市达拉特旗重度盐碱地土壤盐分运移的影响机制。【方法】按照暗管间距18 m、吸水管埋深1.2~1.5 m、集水管埋深1.8~2.0 m的参数，铺设暗管进行田间小区试验，利用空间插值、线性回归、主成分分析等统计方法，对2019年5—10月暗管排水条件下1 m土层的土壤含盐量、地下水埋深、地下水矿化度、灌排水水质、盐分离子等数据及其相互关系进行分析。【结果】①试验区1 m土层的盐分空间分布属于中等变异（25%~75%），土壤盐分类型为表聚型。②铺设暗管使地下水埋深增加了50~60 cm，试验结束时土壤盐分较试验开始时土壤盐分平均降低10%左右。③暗管铺设条件下，土壤盐分的主导离子为K++Na+、SO42-和Cl-，地下水中主导离子为K++Na+、Cl-和HCO3-。④暗管铺设下黄河水灌溉后，土壤中HCO3-量增加56%，而其他盐离子量降低，SO42-、K++Na+、Cl-降幅较大分别为36%、34%、31%；灌水淋洗后，排水、地下水中各离子量均增加，排水矿化度增加幅度是地下水矿化度增加幅度的3.43倍。【结论】重度盐碱地铺设暗管，能控制地下水埋深，并降低土壤含盐量，有效促进土壤中SO42-、K++Na+、Cl-的淋洗排出，但同时要注意黄河水灌溉中HCO3-可能引起的土壤碱化问题。 |
| 关键词: 暗管排水；土壤盐分；空间变异；地下水；离子迁移 |
| DOI：10.13522/j.cnki.ggps.2020634 |
| 分类号: |
| 基金项目: |
|
| The Influence of Subsurface Drain on Solute Movement in Soils Severely Affected by Salinity and Alkalinity in Ordos Region |
|
LI Zhengzheng, QU Zhongyi*, YANG Wei, WANG Liping, GAO Xiaoyu, CHEN Meng
|
|
Water Conservancy and Civil Engineering College, Inner Mongolia Agricultural University, Hohhot 010018, China
|
| Abstract: |
| 【Background】The wide distribution of saline and alkali soils in Ordos of Inner Mongolia is a main abiotic factor hindering crop growth. Their remediation is a prerequisite for developing sustainable agriculture in this region. Subsurface drain is a technology widely used to alleviate salt accumulation and enhance salt leaching. 【Objective】The objective of this paper is to experimentally study the effects of subsurface drain on salt dynamics in soils heavily affected by salinity and alkalinity.【Method】The experiment was conducted from May to October 2015 at Dalat Banner, with the drains spaced 18 m apart and buried in a depth varying from 1.2 m to 1.5 m; the depth of the drainage ditches was 1.8~2.0 m. In each treatment, we measured soil salt distribution up to 1.0 m deep, the change in groundwater table and salinity, as well as the quality of the irrigation water and drainage water, salt ion data and their relationship. 【Result】①Spatial variation of salt in the top 0~100 cm soil was moderate with a coefficient of variation of 25%~75%; the majority of salt was accumulated in regions proximal to the soil surface. ②The drains dropped the groundwater table by 50~60 cm and reduced soil salinity by approximately 10%, compared with data measured before experiment. ③At the end of the experiment, the main salt ions in the soil were K++Na+, SO42- and Cl-, while in the groundwater they were K++Na+, Cl- and HCO3-. ④Irrigating using the Yellow river water increased HCO3- in soil by 56% and the decreased of other salt ions, with SO42-, K++Na+ and Cl- reduced by 36%, 34% and 31% respectively. Leaching of the irrigation water increased ion contents in both drainage water and groundwater, especially the drainage water whose salinity was 3.43 times that of groundwater.【Conclusion】Subsurface drains can control the groundwater depth and reduce soil salt content; it facilitates leaching of SO42-, K++Na+ and Cl- from the soil. However, care should be taken to avoid an increase in HCO3 – and its consequence for soil alkalization when irrigating with the Yellow river water. |
| Key words: |
