Seawater Intrusion and Nitrate Contamination in the Fum Al Wad Coastal Plain,South Morocco  

作　　者：Abderrazak Errich Souad El Hajjaji Mohamed Fekhaoui Belkheir Hammouti Khalil Azzaoui Abdellatif Lamhamdi Shehdeh Jodeh 

机构地区：[1]Laboratory of Spectroscopy,Molecular Modeling,Materials,Nanomaterials,Water and Environment(LS3MN2E-CERNE2D),Department of Chemistry,Faculty of Sciences,Mohammed V University in Rabat,Rabat,Morocco [2]Scientific Institute,Mohammed V University in Rabat,Rabat,Morocco [3]Euro-Mediterranean of Fez(UEMF)BP.15,30070 Fez,Morocco [4]Laboratory of Engineering,Electrochemistry,Modeling and Environment,Faculty of Sciences,Sidi Mohamed Ben Abdellah University,Fez 30000,Morocco [5]Laboratory of Applied Sciences,National School of Applied Sciences d'Al-hoceima,Abdelmalek Essaadi University,BP 03 Ajdir,Morocco [6]Department of Chemistry,An-Najah National University,Nablus,Palestine

出　　处：《Journal of Earth Science》2023年第6期1940-1950,共11页地球科学学刊（英文版）

摘　　要：The coastal plain aquifer down gradient of Wad Essaquia Elhamra(WEE),is the main source of groundwater in the arid region of Laayoune Essaquia El Hamra located in south of Morocco.The over-exploitation of this aquifer over the last decade for water supply,agriculture and industry led to deterioration of groundwater quality,including seawater intrusion.The objective of this study is to investigate the spatial variation of groundwater quality,and to assess the influence of sea water intrusion on the groundwater quality using hydro-chemical tools.Several measurement campaigns of physico-chemical parameters of the groundwater were performed,which shows a very high mineralization ratios versus chloride,confirming the double influence of mixing mechanisms of fresh and saline waters and the water-rock interactions.Computed seawater fraction for sampled water shows that the average mixing rate of seawater intrusion reached 10.5%,confirming the marine intrusion in the aquifer.The highest values were registered in coastal wells.In the upstream around Laayoune and the spreading area,nitrate concentrations exceed 50 mg/L which is the threshold set by the World Health Organization,revealing a high level of contamination by domestic sewage.The combination of ionic ratios and seawater fraction is a useful tool to assess marine intrusion.This study reveals that the phenomenon of marine intrusion is not the only process that dominates hydrochemistry of ground water.The high groundwater mineralization is also due to rockwater interaction associated with reverse ion exchange with clay material and anthropogenic pollutants.

关 键 词：coastal aquifer saltwater intrusion nitrate pollution Fum El Wad aquifer groundwa-ter water supply 

分 类 号：P641.2[天文地球—地质矿产勘探] P731.2[天文地球—地质学] X523[环境科学与工程—环境工程]