孔雀河冲洪积扇灌区包气带水盐运移及其对地下水水质的影响研究

发布时间：2018-04-03 13:47

本文选题：孔雀河冲洪积扇　切入点：灌溉　出处：《吉林大学》2015年硕士论文

【摘要】：孔雀河冲洪积扇地区地处新疆维吾尔自治区巴音郭楞蒙古族自治州库尔勒市，，是巴州政治、经济、文化中心和南北疆重要的交通枢纽和物资集散地，也是我国重要的棉花和香梨的生产基地。区内蒸发强烈，降水稀少，是“无灌溉即无农业”的典型区域。近二十年来农业规模迅速扩大，因此，对灌溉用水的需求量也日益加大。近年来，孔雀河流量大幅度减小，地下水成为孔雀河冲洪积扇灌区农业灌溉的主要水源。目前，孔雀河冲洪积扇地区由于不合理的地下水资源开发利用，已经引发了地下水位下降、地下水咸化等环境地质问题。本文以《库尔勒冲洪积平原地下水资源评价及循环更新能力研究》项目为依托，选取孔雀河冲洪积扇灌区为研究区，研究灌区包气带水盐运移及其对地下水水质的影响。该项研究不仅可以为区域水资源合理开发利用与保护提供科学依据，对解决干旱半干旱地区长期开采地下水灌溉导致的地下水咸化等问题也具有重要意义。论文主要成果如下： 1、结合已有资料开展包气带采样调查，查明了孔雀河冲洪积扇灌区包气带岩性和结构特征； 2、测定包气带土样含水率和含盐量，查明了灌区包气带水盐分布特征，确定包气带水盐分布及运移的主要影响因素为包气带岩性结构、潜水埋深、潜水TDS含量、灌溉方式和灌溉水TDS含量等； 3、采用氯质量累积法计算孔雀河冲洪积扇灌区包气带入渗补给量。灌区包气带的垂向入渗补给总量为181.80-687.58mm/a，灌溉水入渗回归比例为12.37%-28.79%； 4、开展室内土柱模拟实验，研究包气带岩性结构、灌溉水水质和灌溉方式对包气带水盐运移的影响，实验结果表明灌溉水入渗过程中土壤水TDS含量升高主要是强烈蒸发作用下蒸发浓缩引起的； 5、基于室内土柱模拟实验数据，使用Hydrus-1D软件建立包气带水盐运移一维模型，预测长期灌溉驱动下不同包气带岩性和灌溉水水质条件下地下水水质的变化情况。得出长期灌溉影响下不同包气带岩性和灌溉水水质条件下地下水TDS含量均呈升高态势，高TDS含量灌溉水比低TDS含量灌溉水对地下水咸化的影响更大。
[Abstract]:The Kongque River alluvial fan area is located in the Xinjiang Uygur Autonomous region of Bayinguleng Mongolian Autonomous Prefecture, Kurla City. It is the political, economic, cultural and cultural center of Ba Prefecture and an important transportation hub and material distribution center in the north and south of Xinjiang.Also is our country important cotton and fragrant pear production base.The evaporation is strong and the precipitation is rare. It is a typical area of "no irrigation or no agriculture".The scale of agriculture has expanded rapidly in the past two decades, so the demand for irrigation water is increasing day by day.In recent years, the discharge of the river has been greatly reduced, and the groundwater has become the main source of agricultural irrigation in the alluvial fan irrigation area of the river.At present, the unreasonable exploitation and utilization of groundwater resources in the alluvial fan area of the Kongque River have caused environmental geological problems such as the decrease of groundwater level and the salinization of groundwater.Based on the project of "study on groundwater Resources Evaluation and cyclic Renewal ability of Korla Alluvial Plain", this paper studies the migration of water and salt in aeration zone and its influence on groundwater quality.This study can not only provide scientific basis for the rational exploitation and protection of regional water resources, but also solve the problems of groundwater salinization caused by groundwater irrigation in arid and semi-arid areas for a long time.The main results of the thesis are as follows:1. According to the available data, the lithology and structure characteristics of aeration zone in the alluvial fan irrigation area of the Kongquehe River were investigated.2. The moisture content and salt content of soil samples in aeration zone were measured, the distribution characteristics of water and salt in aeration zone were found out, and the main influencing factors of water and salt distribution and migration in aeration zone were determined as lithologic structure of aeration zone, buried depth of groundwater and content of TDS in phreatic water.Irrigation methods and TDS content of irrigation water;3. The chlorine accumulation method is used to calculate the aeration volume in the alluvial fan irrigation area.The total amount of vertical infiltration recharge in the aeration zone is 181.80-687.58mm / a, and the regression ratio of irrigation water infiltration is 12.37- 28.79mm / a;(4) the influence of lithologic structure of aeration zone, water quality of irrigation water and irrigation method on water and salt migration in aerated zone was studied by laboratory soil column simulation experiment.The results showed that the increase of TDS content in soil water during irrigation water infiltration was mainly caused by evaporation and concentration under the strong evaporation.5. Based on the experimental data of indoor soil column simulation, a one-dimensional model of water and salt migration in aerated zone was established by using Hydrus-1D software to predict the variation of groundwater quality under the conditions of lithology of different aeration zones and irrigation water quality driven by long-term irrigation.The results showed that under the influence of long-term irrigation, the TDS content of groundwater increased under the conditions of lithology of different aeration zones and water quality of irrigation water, and the effect of high TDS content irrigation water on groundwater salinization was greater than that of low TDS content irrigation water.
【学位授予单位】：吉林大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：P641.2

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