Aristotle University of Thessaloniki, Department of Geology, Lab. of Engineering Geology & Hydrogeology, 54124 Thessaloniki, Greece; Democritus University of Thrace, Department of Civil Engineering, Xanthi 67100, Greece.
Democritus University of Thrace, Department of Civil Engineering, Xanthi 67100, Greece.
Sci Total Environ. 2018 Apr 15;621:524-534. doi: 10.1016/j.scitotenv.2017.11.235. Epub 2017 Nov 28.
Groundwater constitutes the primary source of fresh water for >1.2 billion people living in coastal zones. However, the threat of seawater intrusion is widespread in coastal aquifers mainly due to overexploitation of groundwater. In the present study, a modified fuzzy multicriteria categorization into non-ordered categories method was developed in order to modify the standard GALDIT method and assess seawater intrusion vulnerability in a coastal aquifer of northern Greece. The method is based on six parameters: groundwater occurrence, aquifer hydraulic conductivity, groundwater level, distance from the shore, impact of the existing status of seawater intrusion, and aquifer thickness. Initially, the original method was applied and revealed a zone of high vulnerability running parallel to the coastline and covering an area of 8.6km. The modified GALDIT-F method achieved higher discretization of vulnerability zones which is essential to build a rational management plan to prevent seawater intrusion. The GALDIT-F approach also distinguished an area of the aquifer that is influenced by geothermal fluids. In total, twenty-five categories were produced corresponding to different vulnerability degrees according to the initial method (High, Moderate, Low) as well as the area influenced by geothermal fluids. Finally, a road map was developed in order to adapt management strategies to GALDIT-F categories and prevent and mitigate seawater intrusion. The proposed management strategies of the coastal aquifer include managed aquifer recharge (MAR) implementation, reallocation of existing wells, optimization of pumping rates during the hydrological year, and a detailed monitoring plan.
地下水是生活在沿海地区的 >12 亿人口的主要淡水来源。然而，由于地下水的过度开采，沿海含水层中的海水入侵威胁普遍存在。在本研究中，开发了一种改进的模糊多准则分类到非有序类别方法，以改进标准的 GALDDIT 方法，并评估希腊北部沿海含水层中的海水入侵脆弱性。该方法基于六个参数：地下水发生、含水层水力传导率、地下水位、距海岸的距离、海水入侵现状的影响以及含水层厚度。最初，应用原始方法揭示了一条与海岸线平行并覆盖 8.6km 面积的高脆弱性带。改进的 GALDDIT-F 方法实现了更高的脆弱性分区离散化，这对于制定合理的管理计划以防止海水入侵至关重要。GALDDIT-F 方法还区分了受地热流体影响的含水层区域。总共根据初始方法（高、中、低）以及受地热流体影响的区域生成了 25 个类别，对应不同的脆弱性程度。最后，制定了路线图，以便根据 GALDDIT-F 类别调整管理策略，预防和减轻海水入侵。沿海含水层的拟议管理策略包括实施含水层人工补给（MAR）、重新分配现有水井、优化水文年内的抽水量以及详细的监测计划。
