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 agricultur-al 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 equa-tions of Engelund and Hansen and Van Rijn respectively used by this model, give Nash performance criteria equal to 0.95 and determination coefficient R2 equal to 0.91. On the other hand, the laying of a coarse gravel layer of median diameter of the grains d50% = 60 mm on the bottom of the channels reduces the rate of sedimentation by about 32% over an 11-year pe-riod. 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.
Water is an essential commodity which affects life and livelihoods in the universe. This study examined perceived ef-fect of water scarcity on livelihoods in Iwoye-Ketu, Ogun State. Random sampling was used to select 80 rural households and water samples for the study. Data collected were analysed using descriptive, inferential and laboratory analyses. Find-ings showed that the mean age of respondents was 38 years with an average household size of four persons. The major sources of water were boreholes (97.5%) and rainwater (90.0%), the average trekking time to the water source was 24 minutes and the households requires an average of 162 litres of water per day. Water analysis’ result showed that the water has pH (6.87), total dissolved solids (0.175 mg∙dm–3), temperature (29.9°C) and turbidity (0.6 FTU). The major causes of water scarcity include insufficient rainfall (97.5%), increased sunlight intensity (97.5%), pollution of water sources (95.0%)and increased population (93.8%). About 60% of them perceived water scarcity to have a negative effect on their liveli-hoods. Correlation analysis shows that there is a significant relationship between usage of water (r = 0.370, p < 0.01) and perceived effect of water scarcity. It was concluded that water available for household use is not sufficient, although it is safe but contain some elements which are not of World Health Organization standard for good potable water. It is recom-mended that the community should build a hub for water collection and distribution close to the village centre and the gov-ernment should provide water infrastructures to increase the supply of potable water.
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 meth-od. The estimation has given 92 mm which is an important quantity. The results of the groundwater microbiological anal-yses 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.
Drought is one of the important phenomena resulting from variability and climate change. It has negative effects on all economic, agricultural and social sectors. The objective of this study is to rapidly detect climate dryness situations on an annual scale at the Mellah catchment (Northeast Algeria) for periods ranging from 31 years through the calculation of: the standardized precipitation index (SPI), the standardized Streamflow index (SSFI), the standardized temperature index (STI). Calculations made it possible to locate periods of drought more precisely by their intensity, duration and frequency, and detect years of breaks using the tests of Pettitt, rang, Lee and Heghinian, Hubert and Buishand. The use of the statistical tests for the rainfall series analyzed show all breaks, the majority of which are in 1996/1997 and 2001/2002. For the tem-peratures the breaks are situated in 1980/1981.
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 wa-ters of the Raszynka River.
In the years 2016–2017, the surface water samples from the Raszynka Rriver (17 points) and soil (19 points) were col-lected 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 nitro-gen (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 electri-cal 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 dependingon 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 Ptotꞏkg–1 in D.M.) and this component may migrate with surface runoff and increase the risk of surface water eutrophication.
The purpose of the article is to present perspectives for the development of offshore wind farms in the leading, in this respect, country in the EU and in the world – Great Britain. Wind power plays a remarkable role in the process of ensuring energy security for Europe since in 2016 the produced wind energy met 10.4% of the European electricity demand while in 2017 it was already around 11.6%. The article analyses the capacity of wind farms, support systems offered by this country and the criteria related to the location of offshore wind farms. The research has been based on the analysis of legal acts, regulations, literature on the subject, information from websites. The article shows that in recent years, the production of energy at sea has been developing very rapidly, and the leading, in this matter, British offshore energy sector is character-ised by strong governmental support.
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 quali-ty on the indicators of ecological stabilization of the landscape and the structure of biotechnical elements. The article de-termines 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 Dnie-per-River cascade within which the tracts of land were identified and the landscape ecological stability (CESL1) and land-scape biotechnical elements coefficients (CESL2) were determined. The retrospective analysis was performed of the sur-face water features on the Right Bank of Polesie region of the Dnieper- River cascade and the main trends in salt block in-dicators, 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 destabili-zation of landscape impact on the water quality formation were defined.
Drought is an extreme event that causes great economic and environmental damage. The main objective of this study is to evaluate sensitivity, characterization and propagation of drought in the Upper Blue Nile. Drought indices: standardized precipitation index (SPI) and the recently developed standardized reconnaissance drought index (RDIst) are applied for five weather stations from 1980 to 2015 to evaluate RDIst applicability in the Upper Blue Nile. From our analysis both SPI and RDIst applied for 3-, 6-, 12 month of time scales follow the same trend, but in some time steps the RDIst varies with small-er amplitude than SPI. The severity and longer duration of drought compared with others periods of meteorological drought is found in the years 1984, 2002, 2009, 2015 including five weather stations and entire Upper Blue Nile. For drought rela-tionships the correlation analysis is made across the time scales to evaluate the relationship between meteorological drought (SPI), soil moisture drought (SMI), and hydrological drought (SRI). We found that the correlation between three indices (SPI, SMI and SRI) at different time scales the 24-month time scale is dominant and are given by 0.82, 0.63 and 0.56.
The dam of Beni Haroun is the largest in Algeria, and its transfer structures feed seven provinces (wilayas) in the east-ern part of Algeria. Due to its importance in the region, it has now become urgent to study its watershed as well as all the parameters that can influence the water and solid intakes that come into the dam. The Soil and Water Assessment Tool (SWAT) model is used to quantify the water yields and identify the vulnerable spots using two scenarios. The first one uses worldwide data (GlobCover and HWSD), and the second one employs remote sensing and digital soil mapping in order to determine the most suitable data to obtain the best results. The SWAT model can be used to reproduce the hydrological cycle within the watershed. Concerning the first scenario, during the calibration period, R2 was found between 0.45 and 0.69, and the Nash–Sutcliffe efficiency (NSE) coefficient was within the interval from 0.63 to 0.80; in the validation period, R2 lied between 0.47 and 0.59, and the NSE coefficient ranged from 0.58 to 0.64. As for the second scenario, during the calibration period, R2 was between 0.60 and 0.66, and the NSE coefficient was between 0.55 and 0.75; however, during the validation period, R2 was in the interval from 0.56 to 0.70, and the NSE coefficient within the range 0.64–0.70. These find-ings indicate that the data obtained using remote sensing and digital soil mapping provide a better representation of the wa-tershed and give a better hydrological modelling.
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, ensuringthe 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.
The objective of this study was to ascertain the socioeconomic and geospatial traits responsible for little or no usage of tractors for land clearing and cultivation by rural farmers in Ogun State, Nigeria. Data were obtained on the study objec-tives with use of interview guide, in-depth discussion and field observation a randomly selected 247 arable crop farmers. The obtained data were subjected to frequency count and binominal analysis of variance. Results showed factors such as farmers’ inability to afford tractor acquisition and/or hire tractors services (prop = 1.00, p < 0.05) as the major economic traits encumbering tractor usage for land preparation. The social traits included inadequate available of tractors to serve the farmers (prop = 0.76, p < 0.05), and farmers’ apprehension of possible destruction of soil structure and/or farm land (prop= 0.64, p < 0.05) as a result of tractor usage for land preparation. The geospatial traits were stump/tree distribution (prop = 0.97, p < 0.05) and land fragmentation (prop = 0.92, p < 0.05). It was thus concluded that both socioeconomic and farmgeospatial traits interactively encumbered farm tractorisation in the study area. It was recommended that farmers should be supported technically and financially by stakeholders in agro-development so as to enable them to afford tractor usage for land cultivation.
Morphological relationships of meander evolution in terms of hydraulic and geometric characteristics are essential for river management. In present study, an experimental based study of meander evolution was employed to develop a predic-tion formula for identifying the pool-point bar location by using the dimensional analysis technique and multiple nonlinear regressions. Through the experimental work on a race of the non-uniform river sand, a set of experimental runs have been carried out through combining different hydraulic and geometric parameters to produce different empirical conditions that have a direct impact on the pool-point bar location. Based on the experimental observations and measurements, the varia-tion in pool–point bar locations could be interpreted to that the hydraulic and morphologic properties through the meander evolution were varied during the time causes the variations in the patterns of the pool-point bar formations accordingly. The developed formula was verified by using another set of the experimental data and tested with three statistical indica-tors. The predicted results indicated that the proposed formula had high reliability for practical estimation of the pool-point bar location. This reliability was tested by the statistical indicators, where the less values have been resulted for bias andmean absolute error (MAE), 0.0004 and 0.0110 respectively, whereas the higher values 0.935 and 0.930 are achieved for the Nash–Sutcliffe efficiency (NSE) and the determination coefficient R2, respectively.
The purpose of the presented research is to analyse possible methods of thickening of the Microcystis aeruginosa (Kützing) Kützing cyanobacteria using the obtained concentrate as a biomass for the production of energy carriers and bio-logically valuable substances. Method of cyanobacteria thickening under the action of electric current and in the electric field, as well as the method of coagulation–flocculation and gravity thickening, was experimentally investigated in lab-scale conditions. Electrical methods didn't show positive results for the Microcystis aeruginosa thickening, despite the re-ports of their potential efficiency in a number of previous studies. The high efficiency of the method of coagulation–flocculation and gravity thickening of Microcystis aeruginosa suspensions was obtained. The optimum concentrations of industrial polymeric coagulants and flocculants for the thickening of Microcystis aeruginosa suspensions were defined in the range of about 10 ppm for the coagulants and about 1 ppm for the flocculants. Negative effect of the previous cavitational treatment of the diluted suspensions of Microcystis aeruginosa on the effectiveness of the coagulation–flocculation and gravitational thickening was confirmed experimentally. Hydrodynamic cavitation should be recommended to use after the thickening as the next step of processing of concentrated suspensions of Microcystis aeruginosa to achieve maximum extraction of energy carriers and biologically valuable substances.
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 ferti-lizers 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 enrich-ment in nutritious elements, phosphorus and nitrogen and particularly, the resulting increase in the aquatic primary produc-tion, 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 neighbour-ing 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 en-vironment and socioeconomic development.
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 em-bankment 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 com-plex 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.
Poland is characterized by a number of factors which adversely affect the agricultural economy, so this paper will aim to present the possibilities of using multi-criteria decision-making methods of Analytical Hierarchy Process (AHP) in the analysis of the spatial structure of rural areas. AHP is a widely used tool for making complex decisions based on a large number of criteria, such as, for example, land consolidation works on fragmented agricultural land. The first step is to formulate the decision-making process, then the assessment criteria and the solution variants guided by expert knowledge are determined.
A ranking, according to which the order of land consolidation and land exchange works in the studied area should be determined, will be defined by using decision-making models of the AHP method. The basis for calculations will be the weights received for the factors/parameters defined for the five thematic groups. Calculations for individual villages will bemade, and then the obtained results will allow creating a ranking for the studied commune, allowing for the effective (in terms of economic and socio-economic) spending of funds for this purpose. The presented method can be successfully used to conduct analogous analyses for any area.
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 tempera-ture of the wetland of Lake Oubeira located in northeastern Algeria and their spatiotemporal evolution in both land and wa-ter. 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 vegeta-tion 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 sur-face, 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.
Groundwater quality modelling plays an important role in water resources management decision making processes. Accordingly, models must be developed to account for the uncertainty inherent in the modelling process, from the sample measurement stage through to the data interpretation stages. Artificial intelligence models, particularly fuzzy inference sys-tems (FIS), have been shown to be effective in groundwater quality evaluation for complex aquifers. In the current study, fuzzy set theory is applied to groundwater-quality related decision-making in an agricultural production context; the Mamdani, Sugeno, and Larsen fuzzy logic-based models (MFL, SFL, and LFL, respectively) are used to develop a series of new, generalized, rule-based fuzzy models for water quality evaluation using widely accepted irrigation indices and hydro-logical data from the Sarab Plain, Iran. Rather than drawing upon physiochemical groundwater quality parameters, the pre-sent research employs widely accepted agricultural indices (e.g., irrigation criteria) when developing the MFL, SFL and LFL groundwater quality models. These newly-developed models, generated significantly more consistent results than the United States Soil Laboratory (USSL) diagram, addressed the inherent uncertainty in threshold data, and were effective in assessing groundwater quality for agricultural uses. The SFL model is recommended as it outperforms both MFL and LFL in terms of accuracy when assessing groundwater quality using irrigation indices.
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 ofheavy 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 la-boratory scale, so it is recommended the simultaneous use of these physico-chemical processes.