Anane Makram, Selmi Youssef, Limam Atef, Jedidi Naceur, Jellali Salah
Wastewater Treatment Laboratory, Water Researches and Technologies Center, Technopark Borj Cedria. Carthage University, P.B. 273, 8020, Soliman-Tunisia, Tunisia,
Environ Monit Assess. 2014 Jul;186(7):4367-90. doi: 10.1007/s10661-014-3705-x. Epub 2014 Mar 28.
In Tunisia, reclaimed water is increasingly used for irrigation in order to mitigate water shortage. However, few studies have addressed the effect of such practice on the environment. Thus, we attempted in this paper to assess the impact of irrigation with reclaimed water on the nitrate content and salinity in the Nabeul shallow aquifer on the basis of satellite images and data from 53 sampled wells. Ordinary and indicator kriging were used to map the spatial variability of these groundwater chemical parameters and to locate the areas where water is suitable for drinking and irrigation. The results of this study have shown that reclaimed water is not an influential factor on groundwater contamination by nitrate and salinity. Cropping density is the main factor contributing to nitrate groundwater pollution, whereas salinity pollution is affected by a conjunction of factors such as seawater interaction and lithology. The predictive maps show that nitrate content in the groundwater ranges from 9.2 to 206 mg/L while the electric conductivity ranges from 2.2 to 8.5 dS/m. The high-nitrate concentration areas underlie sites with high annual crop density, whereas salinity decreases gradually moving away from the coastline. The probability maps reveal that almost the entire study area is unsuitable for drinking with regard to nitrate and salinity levels. Appropriate measures, such as the elaboration of codes of good agricultural practices and action programs, should be undertaken in order to prevent and/or remediate the contamination of the Nabeul shallow aquifer.
在突尼斯，再生水越来越多地用于灌溉，以缓解水资源短缺问题。然而，很少有研究探讨这种做法对环境的影响。因此，本文我们试图基于卫星图像和53口采样井的数据，评估再生水灌溉对纳布勒浅层含水层中硝酸盐含量和盐度的影响。采用普通克里金法和指示克里金法绘制这些地下水化学参数的空间变异性图，并确定适合饮用和灌溉的区域。本研究结果表明，再生水不是硝酸盐和盐度对地下水污染的影响因素。种植密度是导致地下水硝酸盐污染的主要因素，而盐度污染则受海水相互作用和岩性等多种因素的共同影响。预测图显示，地下水中硝酸盐含量范围为9.2至206毫克/升，电导率范围为2.2至8.5 dS/m。高硝酸盐浓度区域位于年作物密度高的地区，而盐度则从海岸线向外逐渐降低。概率图显示，就硝酸盐和盐度水平而言，几乎整个研究区域都不适合饮用。应采取适当措施，如制定良好农业规范和行动计划，以预防和/或修复纳布勒浅层含水层的污染。
