The rivers and their watersheds are fundamental elements of socioeconomic activities. In this article, we analyze the hydrographic basin of the Acaraú River, situated in the northeast of Brazil, from its geoenvironmental aspects, based on the perspective of the geosystem. In this perspective, a geoenvironmental picture of the hydrographic basin in question is presented, as well as the environmental problems that characterize it, postulating the need to carry out this type of survey to define the basin as a fundamental planning unit. The Acaraú River basin has particular characteristics, since it is located in a poor and extremely populous semi-arid region, which results in socio-environmental stress, whose main consequence is the environmental degradation of the fluvial course. The regional authorities need to be aware of the geoenvironmental elements raised in order to reverse this framework of socio-environmental degradation of water resources and to allow territorial growth based on sustainable development.

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The lack of knowledge about fracture systems in Tanda region has led to an approximative establishment of drilling and so a difficult access to groundwater. Thus, a multidisciplinary approach including satellite imagery and electrical resistivity method was conducted with the main objective to locate productive fractures of water in the study area. Indeed, scenes of Landsat 7 ETM + satellite images were used. Also, sixty-two (62) vertical electrical soundings (VES) of the Schlumberger configuration and hundred twenty-nine (129) electrical trailing (ET) were performed with a resistivity-meter SYSCAL Pro. Thanks to different treatments applied to satellite images, structural lineaments have been extracted whose main directions are N00-10 (N-S), N90-100 (E-W), N70-80 and N100-110. The interpretation of electrical trailing data made it possible to validate the lineament map by the determination of the fracturing directions. Those are NW-SE, N-S, NE-SW and to some extent E-W. The result of the electrical sounding data showed the presence of three geoelectric layers comprising firstly cuirass and lateritic clays and possibly topsoil, secondly sands and/or clay sandstone and firdly either granites or sandstones or schists. The second geoelectrical layer corresponds to the potential aquifer because of its relatively low electrical resistivity values (13 Ω•m to 180 or 240 Ω•m). In addition, drillings established at the right of these geological structures provided an average water yield of 4.22 m 3 •h −1 , sufficient for rural hydraulic. Moreover, these results made it possible to obtain a correlation between drilling productivity and the major directions of fracturing. This indicates that the most productive directions are

Study of climate variability gets great importance for integrated water resources management. This work examines impact of climate variability on the evolution of water resources in the Bandama sub-watershed at Sinematiali with a view of better management. The time series of rainfall and discharge were used as a database for this purpose. Known calculation hydrologic methods of Nicholson, Maillet as well as the statistical test for breaking detection (Pettitt test) were applied. The effective rain and recharge were estimated by using the ESPERE software models over the period 1980 to 1987. Climate variability is characterized by alternative season of wet, normal, and dry periods, and a pluviometry break occurred in 1984 year. The annual effective rain was assessed from 30 to 570 mm while recharge of aquifers estimated between 2 and 333 mm. This work constitutes a fundamental base for modeling water resources management at Sinematiali.

A good knowledge of fracturing leads to a better exploitation of the groundwater of the areas in crystalline basement. This study area of interests the catchment of Black Volta area in north eastern Côte d'Ivoire. Its aims to characterize the fracture networks of the catchment of Black Volta. Various methods were used notably mapping using satellite image processing, statistical and geostatistical analysis. The results showed that fracturing of Black Volta area is dense and homogeneous. Statistical analysis of geometric parameter of the fracturing such as fracture lengths and spacing are distributed respectively according to power law and gamma law. The deployment of the fracturing in JGEESI, 19(2): 1-14, 2019; Article no.JGEESI.46635 2 this area is organized and the experimental variogram is characterized by two nested elementary structures. The practical ranges of these two elementary variograms are respectively 34, 5 km to 60 km. Results indicate that the fracturing of Black Volta area reached a stage of advanced development and is complex. Fracturing of Black Volta area is now well known and the groundwater modeling can be undertaking. Review Article