The M’zab region is subject to an arid Saharan climate where surface and sub-surface waters are of little importance. The <span style="font-family:Verdana;">Albian Aquifer</span><span style=&...The M’zab region is subject to an arid Saharan climate where surface and sub-surface waters are of little importance. The <span style="font-family:Verdana;">Albian Aquifer</span><span style="font-family:Verdana;">,</span><span style="font-family:Verdana;"> commonly called Continental Intercalary (CI)</span><span style="font-family:Verdana;">,</span><span style="font-family:Verdana;"> main component</span><span style="font-family:Verdana;"> of North Western Sahara Aquifer System (NWSAS/SASS)</span><span style="font-family:Verdana;">,</span><span style="font-family:Verdana;"> constitutes the most extensive aquifer formation of the region. In our study area</span><span style="font-family:Verdana;">, </span><span style="font-family:Verdana;">the CI is identified</span><span style="font-family:Verdana;">,</span><span style="font-family:Verdana;"> as a regional subset</span><span style="font-family:Verdana;">,</span><span style="font-family:Verdana;"> as the Albian Aquifer of M</span><span style="font-family:Verdana;">’</span><span style="font-family:Verdana;">zab Region (AAMR). Its groundwater resources are considered the only source available to meet the growing needs of drinking water supply</span><span style="font-family:Verdana;">,</span><span style="font-family:Verdana;"> agriculture and industry. This aquifer is heavily exploited by a very large number of wells (more than 750). Its supply is very low</span><span style="font-family:Verdana;">,</span><span style="font-family:Verdana;"> so it is a very low renewable layer. This requires periodic monitoring and control of its piezometric level and its physico-</span><span style="font-family:;" "=""> </span><span style="font-family:Verdana;">chemical quality. The objective of our study is to know the current state of this aquifer</span><span style="font-family:Verdana;">, </span><span style="font-family:Verdana;">while studying the variation of its piezometry for the period 2010</span><span style="font-family:Verdana;">-</span><span style="font-family:Verdana;">2018</span><span style="font-family:Verdana;">,</span><span style="font-family:;" "=""><span style="font-family:Verdana;"> and also the chemical quality of its groundwater by analyzing </span><span style="font-family:Verdana;">more than 90 samples over the entire study area. The application of geostatistics</span> <span style="font-family:Verdana;">by kriging and the steps of analysis</span></span><span style="font-family:Verdana;">,</span><span style="font-family:Verdana;"> modelling and calculation of semivariogram</span><span style="font-family:Verdana;"> have enabled us to draw up maps of the various hydrogeological and hydrochemical parameters. As a result</span><span style="font-family:Verdana;">,</span><span style="font-family:Verdana;"> twelve thematic maps were gridded using Geostatistical tools of ArcGIS software. The water-level-change map showed a significant drop in the groundwater level over the entire M</span><span style="font-family:Verdana;">’</span><span style="font-family:Verdana;">zab region and especially around the major cities (Gharda<span style="white-space:nowrap;">ï</span>a</span><span style="font-family:Verdana;">, </span><span style="font-family:Verdana;">Berriane</span><span style="font-family:Verdana;">,</span><span style="font-family:Verdana;"> Metlili and Zelfana) with more than 8 meters. Chemical analyses of the Albian groundwater in the study area show the dominance of evaporite facies (Cl</span><sup><span style="font-family:Verdana;">-</span></sup><span style="font-family:Verdana;">-</span><span style="font-family:;" "=""><span style="font-family:Verdana;">Na</span><sup><span style="font-family:Verdana;">+</span></sup></span><span style="font-family:Verdana;">-</span><span style="font-family:;" "=""><span style="font-family:Verdana;">Ca</span><sup><span style="font-family:Verdana;">2+</span></sup><span style="font-family:Verdana;">) with low concentrations than the Algerian Standards for Drinking (ASD). All the water quality indices (WQI) that have been mapped reveal that the groundwater samples were suitable for drinking and irrigation with a high quality of water located in the south of the study area.</span></span>展开更多
文摘The M’zab region is subject to an arid Saharan climate where surface and sub-surface waters are of little importance. The <span style="font-family:Verdana;">Albian Aquifer</span><span style="font-family:Verdana;">,</span><span style="font-family:Verdana;"> commonly called Continental Intercalary (CI)</span><span style="font-family:Verdana;">,</span><span style="font-family:Verdana;"> main component</span><span style="font-family:Verdana;"> of North Western Sahara Aquifer System (NWSAS/SASS)</span><span style="font-family:Verdana;">,</span><span style="font-family:Verdana;"> constitutes the most extensive aquifer formation of the region. In our study area</span><span style="font-family:Verdana;">, </span><span style="font-family:Verdana;">the CI is identified</span><span style="font-family:Verdana;">,</span><span style="font-family:Verdana;"> as a regional subset</span><span style="font-family:Verdana;">,</span><span style="font-family:Verdana;"> as the Albian Aquifer of M</span><span style="font-family:Verdana;">’</span><span style="font-family:Verdana;">zab Region (AAMR). Its groundwater resources are considered the only source available to meet the growing needs of drinking water supply</span><span style="font-family:Verdana;">,</span><span style="font-family:Verdana;"> agriculture and industry. This aquifer is heavily exploited by a very large number of wells (more than 750). Its supply is very low</span><span style="font-family:Verdana;">,</span><span style="font-family:Verdana;"> so it is a very low renewable layer. This requires periodic monitoring and control of its piezometric level and its physico-</span><span style="font-family:;" "=""> </span><span style="font-family:Verdana;">chemical quality. The objective of our study is to know the current state of this aquifer</span><span style="font-family:Verdana;">, </span><span style="font-family:Verdana;">while studying the variation of its piezometry for the period 2010</span><span style="font-family:Verdana;">-</span><span style="font-family:Verdana;">2018</span><span style="font-family:Verdana;">,</span><span style="font-family:;" "=""><span style="font-family:Verdana;"> and also the chemical quality of its groundwater by analyzing </span><span style="font-family:Verdana;">more than 90 samples over the entire study area. The application of geostatistics</span> <span style="font-family:Verdana;">by kriging and the steps of analysis</span></span><span style="font-family:Verdana;">,</span><span style="font-family:Verdana;"> modelling and calculation of semivariogram</span><span style="font-family:Verdana;"> have enabled us to draw up maps of the various hydrogeological and hydrochemical parameters. As a result</span><span style="font-family:Verdana;">,</span><span style="font-family:Verdana;"> twelve thematic maps were gridded using Geostatistical tools of ArcGIS software. The water-level-change map showed a significant drop in the groundwater level over the entire M</span><span style="font-family:Verdana;">’</span><span style="font-family:Verdana;">zab region and especially around the major cities (Gharda<span style="white-space:nowrap;">ï</span>a</span><span style="font-family:Verdana;">, </span><span style="font-family:Verdana;">Berriane</span><span style="font-family:Verdana;">,</span><span style="font-family:Verdana;"> Metlili and Zelfana) with more than 8 meters. Chemical analyses of the Albian groundwater in the study area show the dominance of evaporite facies (Cl</span><sup><span style="font-family:Verdana;">-</span></sup><span style="font-family:Verdana;">-</span><span style="font-family:;" "=""><span style="font-family:Verdana;">Na</span><sup><span style="font-family:Verdana;">+</span></sup></span><span style="font-family:Verdana;">-</span><span style="font-family:;" "=""><span style="font-family:Verdana;">Ca</span><sup><span style="font-family:Verdana;">2+</span></sup><span style="font-family:Verdana;">) with low concentrations than the Algerian Standards for Drinking (ASD). All the water quality indices (WQI) that have been mapped reveal that the groundwater samples were suitable for drinking and irrigation with a high quality of water located in the south of the study area.</span></span>
