Hydrochemical assessment and groundwater pollution parameters in arid zone: Case of the Turonian aquifer in Béchar region, southwestern Algeria
Ikram MOKEDDEM, Meriem BELHACHEMI,
Touhami MERZOUGUI, Noria NABBOU, Salih LACHACHE
Abstract: Groundwater samples from Turonian aquifer of Béchar region were evaluated as drinking and irrigation water sources.
physicochemical parameters including pH, EC, TH, Na+
, Ca2+, Mg2+, Cl–
, SO4
2– and NO3
– were determined for 16 water
sampling points. These characterizations show that the groundwater is fresh to brackish, slightly alkaline and the major ions
are Na+
, Ca2+, Mg2+, Cl–
and SO4
2–. According to WHO standards, 50% of the analysed water are suitable as a drinking
source while the other samples are not in compliance with drinking water standards. This non-compliance is basically due
to the high concentrations of Na+
, Cl–
, and SO4
2– requesting further treatment to reach the stringent standards. According to
the results of nitrate concentrations, anthropogenic source seems to influence the groundwater quality. The present study
shows that Béchar groundwater may represent an important drinking and irrigation water source. However, a specific management
strategy should be adapted in order to avoid the contamination by anthropogenic sources.
Key words: Béchar region, groundwater, hydrochemistry, Turonian aquifer, water quality
Quality of Hamadian groundwater table of the continental tertiary of Wadi Mehiya in Tindouf province (South-West of Algeria)
Mohamed F. BEKKOUCH and Ahlam ZANAGUI
Abstract: The Hamadian groundwater table ensures water supply for the agricultural perimeter of Wadi Mehiya region in the
North-East of Tindouf city. In order to determine the behaviour of this groundwater table, a piezometric map have been
realized, followed by physicochemical analyses to assess the chemical facies, the suitability of this water for irrigation and
drinking purposes, as well as its vulnerability to different pollutants. This groundwater table is essentially composed of fine
to coarse and clayey sands, surmounted by a silicified limestone slab. It is a free groundwater table with a thickness of 18 to
99 m. The sampling has been done in June 2010. Then, the physicochemical analyses have been performed on 7 samples
taken from 7 boreholes. The piezometric study proved that the flow of groundwater table follows a North-East to South-
-West direction, towards the Sebkha of Tindouf. The graphic representation of chemical facies, using Piper and Schoeller–
Berkaloff diagrams, reveals that the water of Wadi Mehiya contains mainly magnesium sulphate. The graphical representation
of irrigation water quality, using Wilcox diagram, revealed an acceptable quality with a high salinity. Moreover, this
water is potable with hard-mineralized character. Nitrates contamination has been also noted, which is a logical result of the
excessive use of chemical fertilizers.
Key words: Hamadi groundwater table, irrigation, quality, salinity, vulnerability, Wadi Mehiya
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