Caractérisation Physico-Chimique Des Eaux De Surface Et Étude De La Diversité Ichtyologique De Quelques Zones Humides Continentales En Mauritanie

Abstract

The aim of this study is to characterize the physicochemical parameters of the waters of certain continental wetlands and to determine the fish population diversity of this aquatic habitat in Mauritania. Physico-chemical analyses carried out in 2015-2016 (wet-fresh, hot-dry) suggest the qualities of good water, favorable to aquatic life at any time of the year. The highest values were recorded in the warm season (from 26.6 to 34.4 °C for the temperature, from 8 to 9.2 for the pH, from 170 to 591 μs/cm for the conductivity, from 3, 23 to 8.2 mg / l for dissolved oxygen and 169 to 590 mg / l TDS). The lowest values were found in the cold season (from 18.0 to 27.0 ° C for temperature, from 7.5 to 9.0 for pH, from 99.5 to 358 μs/cm for conductivity, 2.70 to 4.80 mg/l for dissolved oxygen and 100 to 360 mg/l of TDS). The establishment and development of biodiversity in these wetlands were at their peak during the hot and dry periods. 15 species belonging to 8 families were identified in these sites where there is a significant fishing activity. It is during this period that fish biodiversity and fishery potential increase as water decreases under the pressure of evaporation, infiltration and anthropozoogenic consumption. The ecosystem services of these continental wetlands, which survive the impacts of climate change, require urgent management, preservation and development measures.

First Physico-Chemical and Traditional Characterisation of Lake Tseny, Northwest Madagascar

“…The lake temperature was similar to the mean air temperature at the study site (data from the data logger in this study) and was related to the difference in air temperature between seasons, which was slightly higher in the rainy period (28.58 °C) than in the dry period (28.07 °C), indicating that the water temperature is related to the ambient temperature of study area and period (Tfeil et al, 2018). The comparison with Lake Kinkony, the northwestern lake, showed similar values varied between 29.8°C and 34.7°C (Rasoloariniaina, 2010).…”

Caractérisation De La Qualité De L’eau De La Rivière Tsiandanitra De Fianarantsoa Madagascar : Cas Des Eaux Traversant Andrainjato Nord

“…Selon les indications de [16], les eaux de la rivière Tsiandanitra restent dans le seuil de tolérance (500 µS/cm) pour la survie des poissons et ne posent pas de risques pour la consommation du point de vue de la conductivité. En ce qui concerne le TDS, il est un paramètre équivalent à la teneur en ions organiques et inorganiques dissous dans l'eau [17]. Les solides totaux dissous partagent une forte corrélation avec la conductivité électrique pour la présente étude (Tab.…”

“…Concordant ainsi avec le travail réalisé par [18] qui a indiqué une conductivité électrique fortement corrélée aux TDS dans la rivière d'Omoku Creek, au Nigéria. Le profil de variation du TDS qui est proportionnel à l'évolution de la conductivité confirme donc la minimalité d'effet préjudiciable lié à la qualité de ces eaux suite aux faits qu'il est inférieur à la norme (400ppm) pour une eau douce potable [17] et est dans le seuil tolérable de l'OMS. Par ailleurs, les ions chlorures sont des composants naturels des eaux.…”

Spring quality assessment and effects on the health of inhabitants of Santa Sub-Division, North West Region, Cameroon

“…The HCO 3 and H + may also increases the acidity of the water. The low concentrations of sulphate ions in the water sources could result from SO 2 and H 2 S dissolution, oxidation of anhydrite, gypsum, application of fertilizers and detergents (Jain et al, 2006;Abboudi et al, 2014). Excess of SO 4 2in water sources will lead to adverse health situations such as gastro-intestinal problems.…”