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Abstract

Surface water of Kébir Rhumel basin is indispensable for domestic and industrial needs of this region. Industrial development, with water excessive use and chemical products, in production and industrial treatment, and not sustainable fertilizers in agriculture, constitutes a serious threat to maintain our resources of good water quality. The majority of domestic and industrial wastewaters of the region, discharged to the stream water of Kébir Rhumel basin, promote the water enrichment in nutritious elements, phosphorus and nitrogen and particularly, the resulting increase in the aquatic primary production, mainly the planktonic or benthic algae. As a result, the physical and chemical properties of water deteriorate.

This basin allows construction of the largest dam in Algeria “Beni-Haroun dam”. The infrastructure that was one of the greatest challenges of Algeria is now a reality. Hydraulic complex of Beni-Haroun remains a strategic and major achievement in the development program of water resources sector. This enormous building was constructed in the territory of the Wilaya (province) of Mila, used to meet water needs, with four million inhabitants, of eastern Algeria and other neighbouring regions that have suffered from lack of water consumption, especially in summer. In addition, it will irrigate over 42 000 ha, going thus to the several plains.

Integration of sociological and environmental concerns into dams design is a recent phenomenon. It is considered at the impact study level, during which the dam study project is accompanied by a survey to assess project impact on natural environment and socioeconomic development.

Abstract

The article focuses on the problem of structure degradation and ecosystem functioning – the urgency that identifies the relevance of operations at a strategic level aimed at providing the integrated assessment of ecological stability of water. Determination of water quality indicators were divided into blocks according to the criteria of salt composition, according to chemical saprobological indicators and the content of specific substances of toxic and radiation action. According to the results of block analysis, the integrated ecological index of water quality was determined by the dependence of water quality on the indicators of ecological stabilization of the landscape and the structure of biotechnical elements. The article determines the relationships between worsening quality of surface waters and stabilization or destabilization of the landscape structure. The research was conducted on medium and large streamflows on the Right Bank of Polesie region of the Dnieper-River cascade within which the tracts of land were identified and the landscape ecological stability (CESL1) and landscape biotechnical elements coefficients (CESL2) were determined. The retrospective analysis was performed of the surface water features on the Right Bank of Polesie region of the Dnieper-River cascade and the main trends in salt block indicators, trophic and saprobiological block indicators, and in the content of toxic and radioactive substances at observation sites were estimated. Based on obtained data, the integrated assessment in trends of surface water quality on the Right Bank of Polesie region of the Dnieper-River cascade was made and the main parameters and scale of stabilization and destabilization of landscape impact on the water quality formation were defined.

Abstract

The Henaya Irrigated Perimeter (HIP) is an agricultural area irrigated by treated wastewater (TWW) of Ain El Hout treatment plant. Various analyses have shown that i) this water has low concentration of heavy metals and toxic elements, ii) the average values of the physicochemical parameters for 136 samples are satisfactory (29.2 mg O2∙dm−3 for chemical oxygen demands – COD, 13.14 mg O2∙dm−3 for biological oxygen demands – BOD, 14.2 mg∙dm−3 of suspended matter – SM, 1.82 mg∙dm−3 of N-NO3, 7.7 for pH and 927.74 μS∙cm−1 for electric conductivity – EC). Thirdly, it contains a high number of bacteria and nematodes (7200 CFU∙(100 dm3)−1 for faecal coliforms and 30 eggs∙dm−3 for intestinal Nematodes) which makes it dangerous for groundwater contamination.

The objective in this work is to characterize the TWW and evaluate the impact of it use for irrigation on the quality of Hennaya groundwater. Before this, one has to prove that there is an amount of TWW that feeds the water table to show that there is a risk of pollution. We then estimated the aquifer minimum recharge value by TWW using the Thormthwaite method. The estimation has given 92 mm which is an important quantity. The results of the groundwater microbiological analyses reveal no sign of contamination. The cause is the efficiency of the degradation of pollutants of the Vadose zone. The soil purifying power Md of the HIP was evaluated by the Rehse method and gave values ranging from 2.1 to 12.7 which indicated a complete purification.

Abstract

In the context of climate change, it is important to minimize the changes that are introduced in the territory adjacent to the object of human economic activity. In some cases, this can be done with the help of drainage-screened modules – an anti-filtration screen that redistributes the zone of influence of the drain placed near it. As a result, the drain regulates to a greater extent the zone of human economic activity (drainage system, tailing dump, populated area, etc.) and to a lesser extent lowers the level of groundwater in the adjacent territory. The use of drainage-screened modules in tailing farms, for the organized storage of mineral waste of enterprises makes it possible to increase the filtration stability of dike, ensuring the uniform operation of the tailing dams, as well as reliable removal of intercepted groundwater. This is achieved because in the tailing farm the dikes are intensified by drainage-screened modules. Water, filtered through the body of the dike and under it, is intercepted by a drain. A part of the filtration flow, which is not intercepted by the drain, is stopped by the anti-filtration screen.

Abstract

The aim of the study was to assess the content of soluble forms of fertilizer nutrients (N, P, K) in the cultivated soil layer up to 20 cm deep from agricultural land in the river valley, and the concentration of these nutrients in the surface waters of the Raszynka River.

In the years 2016–2017, the surface water samples from the Raszynka Rriver (17 points) and soil (19 points) were collected from agricultural areas near the Raszynka River.

The surface water samples were collected once a month during the March–October 2016–2017. The contents of nitrogen (Ntot, NO3-N and NH4-N), phosphorus (Ptot, PO4-P), total organic carbon (TOC and K and Ca) in soils and in waters were determined in the sample solutions.

It was shown that river water was of low quality due to the high concentration of nitrogen and phosphorus and electrical conductivity (EC). The most polluted were the waters of the lower section of the river located in the vicinity of arable land and agricultural built-up areas. The soluble forms of nutrients content in the cultivated soil layer was varied depending on the kind of nutrient, way of agricultural land use, and the term of soil sampling. The content of dissolved P forms in the soil was the highest in autumn on arable lands after harvesting of vegetables (GO-W: 10.24 mg Ptot·kg−1 in D.M.) and this component may migrate with surface runoff and increase the risk of surface water eutrophication.

Abstract

This paper presents the groundwater modelling of Beni Abbes palm grove in Southwest Algeria. Beni Abbes oasis alluvial aquifer is part of the Saoura Valley aquifer system, including a loose slick contained in a Quaternary alluvial embankment that fills the Beni Abbes basin. To address local needs, industry and agriculture, groundwater has been intensively exploited in recent years. Groundwater of the Beni Abbes oasis in the Saoura Valley oasis chain, is composed of a complex system, whose layer of alluvial terraces ensures a vital role for a 40-hectare palm grove. Due to its architectural position in the local aquifer system, the alluvial aquifer is mainly fed by the Great Western Erg and sometimes by the Saoura River floods. Based on the hydrogeological, hydrochemical characterisation and hydrodynamic modelling of the alluvial aquifer system of the Beni Abbes oasis, the mathematical model of finite difference and finite difference at steady state leads to the estimation of the hydrodynamic parameters of the aquifer and the evaluation of the complete water balance. The main results of this study provide a better understanding of the geometry and functioning of this aquifer currently in a state of concern. Furthermore, it is necessary to undertake integrated water resource management in this oasis in order to ensure sustainable development.

Abstract

This investigation was undertaken to determine the optimum conditions for physical-chemical treatment of waste water contaminated with heavy metals in the industry of metallic coatings. The industry uses substances such as: inorganic acids, alkalis, acidic and alkaline metal salts, that has a high water demand in the processes of flushing and cleaning the parts to be coated. According to the preliminary characterization of samples and reported in the literature theory, physico-chemical process was implemented for the removal of contaminants that consisted in chemical oxidation of CN-ions, followed by chemical precipitation made next to a coagulation/flocculation and subsequent adsorption on activated coal. Laboratory scale tests showed the optimal conditions of treatment including chemical oxidation by the addition of 4.15 cm3 of H2O2 (30%) per gram of CN, chemical precipitation with NaOH to a pH of 12, followed by coagulation/flocculation with Fe2(SO4)3 at a speed of 135 rpm for 3 min and 20 rpm for 20 min and finally the addition of 1.0 g of adsorbent previously activated at 700°C. From this study, it is clear that the adsorption on activated carbon is highly efficient in the removal of heavy metals from industrial waste water from electroplating. However, it is also clear that the parallel application of the treatments, shown here, is more effective to completely remove contaminants such as lead, nickel, silver, and copper at laboratory scale, so it is recommended the simultaneous use of these physico-chemical processes.

Abstract

The difficulties of access and detailed measurements of land surface temperature (LST) and water surface temperature (WST) especially in wetlands made the use of remote sensing data as one of the sources and techniques to estimate many climate elements including surface temperature and surface emissivity (ɛ). This study aims to estimate the surface temperature of the wetland of Lake Oubeira located in northeastern Algeria and their spatiotemporal evolution in both land and water. Landsat OLI-TIRS images in two dates (April and September 2016) obtained from the USGS have been used in this work, and forms the basis of a series of operations to obtain the final LST: development of the normalized difference vegetation index (NDVI), conversion of the digital number (DN) of the thermal infrared band (TIR) into spectral radiance as well as the calculation of the effective luminosity temperature of the sensor from the spectral radiation and surface emissivity (ɛ).

The results show that the LST varies in space and time (from 16 to 31°C in April and from 24 to 41°C in September). This implies that the absorption of the equilibrium temperature at land cover depends on the optical properties of the surface, which are essentially determined by its water content, colour and morphology. At the same time, the water surface is the lowest land cover temperature, which also has a spatial variation (from 19 to 25°C in April and from 26 to 34.5°C in September) induced by atmospheric temperature, wind direction and speed and the depth of the lake.

Abstract

Agricultural drainage has become a priority in agriculture and the economic development of the state. Algeria has launched several agro-economic projects pertaining to natural resources and human potential for development in agricultural areas. Our aim is to model the morphological evolution of open drainage channels, under the influence of sedimentary transport processes. The application of the Hydrologic Engineering Center’s River Analysis System (HEC-RAS) software is to examine two-phase mathematical models. In our case it is the flow and the sedimentary charge along a trapezoidal earth channel of a wetland north east of Algeria. The results of these models were validated by actual data obtained during the observation period from 2017 to 2018, for various rainy events. The solid transport and sedimentation velocity equations of Engelund and Hansen and Van Rijn respectively used by this model, give Nash performance criteria equal to 0.95 and determination coefficient R 2 equal to 0.91. On the other hand, the laying of a coarse gravel layer of median diameter of the grains d 50% = 60 mm on the bottom of the channels reduces the rate of sedimentation by about 32% over an 11-year period. This satisfying objective study of the modelling allows to obtain an approach to the renovation and a plan for new design of drainage systems, that participates to the sustainable development in the agricultural field.

Abstract

River water pollution has been reported globally. In suggestion to adapt sustainability approach, this study carry out to tests the structural equation model between sustainable development and water resources management in the Malacca River basin (Malaysia). The model consists of six latent constructs (anthropogenic activities; law, regulation and policy; land and water ecosystem; Malacca River; river water pollution; sustainability) and twenty four items based on 400 questionnaires which were completed and returned by the local residents of Malacca state. Selected study area is within Malacca River basin. The result show the Malacca River is influenced by water law-regulation-policy (β = 0.546, p < 0.001), anthropogenic activities (β = 0.145, p < 0.001), river water pollution (β = 0.142, p < 0.001), land and water ecosystem (β = 0.105, p < 0.01), as well as sustainable approach (β = 0.127, p < 0.5). It was found that a sustainable approach and water law-regulation-policy have a direct influence on anthropogenic activities, river water pollution, as well as the land and water ecosystem. In conclusion, this study suggests developing an earlier approach of the model involved with water resources management and sustainable development.