摘要
海水入侵已经成为全球范围内的环境问题,严重制约着沿海城市的可持续发展,其中不同类型海岸带的海水入侵方式和危害程度也不同。以深圳市东海岸为研究区,基于区域渗流对局域渗流的总体控制优势,采用多尺度耦合模拟方法,建立研究区区域尺度及典型海岸带局域尺度的三维变密度溶质运移模型,并通过数值模拟方法讨论多种情景下研究区不同类型海岸带的海水入侵机理与地下水水质演化规律。结果表明:(1)研究区河口海岸、基岩海岸和砂质海岸的海水入侵机理和海水入侵距离显著不同;(2)在保持当前禁止开采地下水政策条件下,未来五年内研究区不同类型海岸带的海水入侵均发生不同程度的回退;(3)在678万m^(3)/a开采地下水条件下,研究区河口海岸的最大海水入侵距离的增长速率为0.066 km/a,基岩海岸和砂质海岸的海水入侵速率分别为0.026 km/a和0.076 km/a,砂质海岸的海水入侵速率约为基岩海岸的3~4倍。
Seawater intrusion has become a global environmental problem,which seriously restricts the sus-tainable development of coastal cities.However,there are big difference in the process of seawater intrusion and the degree of harm in different types of coastal zones.Taking the east coast of Shenzhen as the study area,a three-dimensional variable density solute transport model on the regional scale and the local scale of a typical coastal zone was established using a multi-scale coupled simulation method based on the overall control advantage of regional seepage over local seepage.Then,we discussed the seawater intrusion mecha-nism and groundwater quality evolution law in different types of coastal zones under various scenarios.The results are as follows:①The mechanisms and intruding distances of seawater intrusion are significantly different between estuarine coast,bedrock coast and sandy coast;②Under the current policy of prohibiting groundwater exploitation,seawater intrusion in different types of coastal zones in the study area will expe-rience varying degrees of regression over the next five years;③Under groundwater exploitation conditions of 6.78 million m/a,the growth rate of the maximum seawater intrusion distance of the estuary coast is 0.066 km/a,the seawater intrusion rates of the bedrock coast and sandy coast are 0.026 km/a and 0.076 km/a,respectively,and the rate of seawater intrusion of sandy coasts is 3-4 times larger than that of bed-rock coasts.
作者
宋绍宇
成建梅
程天舜
卢薇艳
职敬儒
SONG Shaoyu;CHENG Jianmei;CHENG Tianshun;LU Weiyan;ZHI Jingru(School of Environmental Studies,China University of Geosciences(Wuhan),Wuhan 430078,China;Shenzhen Water Planning&Design Institute Co.,Ltd.,Shenzhen 518023,China;Shenzhen Municipal Bureau of Geology,Shenzhen 518023,China)
出处
《安全与环境工程》
CAS
CSCD
北大核心
2023年第5期174-184,共11页
Safety and Environmental Engineering
基金
国家自然科学基金项目(U1911205、42172278)。
关键词
海水入侵
不同类型海岸带
多尺度耦合
数值模拟
深圳市东海岸
seawater intrusion
different type of coastal zone
multi-scale coupling
numerical modeling
east coast of Shenzhen
