一种可增加海岛地下淡水资源储量的方法研究  

A method for improving the fresh groundwater storage of oceanic islands

作　　者：马婧 鲁春辉 吴吉春[3] 罗剑 MA Jing;LU Chunhui;WU Jichun;LUO Jian(College of Water Conservancy and Hydropower Engineering, Hohai University, Nanjing, Jiangsu 210098, China;State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering, Hohai University, Nanjing, Jiangsu 210098,China;School of Earth Sciences and Engineering, Nanjing University, Nanjing, Jiangsu 210023,China;School of Civil and Environmental Engineering, Atlanta, Georgia 30331,US)

机构地区：[1]河海大学水利水电学院,江苏南京210098 [2]河海大学水文水资源与水利工程科学国家重点实验室,江苏南京210098 [3]南京大学地球科学与工程学院,江苏南京210023 [4]美国佐治亚理工学院土木与环境工程系,佐治亚州亚特兰大30331

出　　处：《水文地质工程地质》2020年第3期1-7,共7页Hydrogeology & Engineering Geology

基　　金：国家重点研发计划(2016YFC0402800);国家自然科学基金资助项目(51679067)。

摘　　要：淡水透镜体作为海岛上珍贵的地下淡水资源,对于满足居民生活用水与维护生态系统具有重要作用,增加海岛地下淡水资源储量可有效缓解海岛地区普遍存在的水资源短缺问题。本研究提出通过在海岛外部区域采用低渗透性介质材料增加海岛地下淡水资源储量的方法,采用室内物理模型实验与基于变密度地下水流溶质运移模型的数值模拟相结合的方法对提出方法的有效性进行了验证,并通过野外尺度的数学模型分析工程实施可能性。实验与数值模拟结果较吻合,表明该方法具有抵御海水入侵、增加海岛地下淡水资源储量的巨大潜力。通过基于野外尺度的数值模拟分析工程实施的可能性,发现对于降雨入渗补给强度为0.0057 m/d、长度为200 m,孔隙度为0.3的狭长形均质海岛,地下淡水储量为66.5 m^3/m,在海岛外部区域采用渗透系数为1 m/d、厚度为5 m的低渗透性介质材料后,淡水透镜体经过约8 a时间可再次达到稳态,地下淡水储量为343.8 m^3/m,增加约4倍,工程实施具备一定可能性。本研究为缓解海岛地区缺水问题、实现淡水资源可持续利用提供了一种新方法。There are many natural and artificial islands in our country,where the freshwater lens are precious freshwater resource and play an important role in supporting domestic water and the health of the groundwater-dependent ecosystems.Improving the groundwater storage of islands can effectively mitigate the widespread issues of water resources shortage of islands.This study presents some methods capable of improving oceanic fresh groundwater storage by using a low-permeability medium along the shore line.The effectiveness of the proposed method is validated through experimental and numerical studies.Field-scale numerical models are developed to analyze the possibility of the field application.The experimental fresh water-saltwater interface result is in good agreement with the numerical result,indicating that the proposed method has a great potential in preventing seawater intrusion and improving the freshwater storage.The numerical results show that for an imaginary island,the fresh groundwater storage can be increased by about 5 times after 8 years since the project is implemented.This study provides a new method for alleviating the issue of water resources shortage and realizing sustainable use of freshwater resources in island areas.

关 键 词：海岛 淡水透镜体 渗透系数 室内实验 数值模拟 

分 类 号：P641[天文地球—地质矿产勘探] X173[天文地球—地质学]