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Applied structural equation model in sustainable development of water resources management

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.

Open access
Applying results of the chemical analyses in determining groundwater quality for drinking, agricultural and industrial uses: The case study Rafsanjan plain, Iran

Abstract

Based on chemical analyses, the quality of ground waters for drinking, agricultural and industrial purposes was determined in Rafsanjan Plain-Iran. Samples for analyses were taken from 22 wells in 2012. Because of high water hardness and total dissolved solids content, water was found to be unsuitable for drinking purposes. Water quality for agriculture was determined with the use of the Wilcox method. Among the analysed water, 10.33% were attributed to C3-S1 class (high electrolytic conductivity and low sodium adsorption ratio), 59.5% to class C4-S1 (very high EC and low SAR) and 30.17% to class C4-S2 (very high EC and medium SAR). 89.67% of studied wells were unsuitable for agriculture. Because of corrosive water properties all but two wells on Rafsanjan Plain were undesirable for use in the industry. The results of qualitative analyses were presented in GIS and in databases to support making decision and management of groundwater on Rafsanjan Plain.

Open access
Assessment of physicochemical and bacteriological groundwater quality in irrigated Triffa Plain, North-East of Morocco

Abstract

The physicochemical and bacteriological quality of groundwater was assessed to show the impact of the agriculture and human activities in the Triffa Plain located in North-East of Morocco. The current levels of contamination of the groundwater were estimated by analysing electrical conductivity, nitrate, nitrite, ammonia, orthophosphate, and indicators of faecal pollution content.

Water samples from 55 locations were collected during two period of time, the wet and the dry season of the year 2016. Result obtained indicated that most samples are highly contaminated. The electrical conductivity varied from 800 to 9 100 μS∙cm−1. Nitrate levels ranged from 25 to 216 mg·dm−3, with 78% of samples exceeding the critical level value set at 50 mg·dm−3. Nitrate concentrations are slightly higher during the wet period in 73% of studied cases. Nitrite rarely exceeded the normal rate fixed by World Health Organization and reached 0.90 mg·dm−3. Ammonia and orthophosphate contents do not exceed these norms.

The study revealed a wide contamination of groundwater by microbial agents such as, total coliforms, faecal coliforms and faecal streptococci, with content ranged from 0 to 14 000, 0 to 5 000 and 0 to 5 000 CFU·(100 cm3)−1 respectively, confirming the impact of septic tanks, wastewater discharge into rivers without treatment, and the use of animal waste on the ground water vulnerability.

Samplings and measurements were carried out according to the international standard ISO 13395, ISO 11732 and ISO 15681-2 for chemical compounds and ISO 9308-1 and ISO 7899-2 for microbiological numerations.

Open access
Dynamics of changes in surface water quality indicators of the Western Bug River basin within Ukraine using GIS technologies

Abstract

The environmental assessment of the surface water quality of the Western Bug River has been made using the system of classification quality of land surface water of Ukraine in accordance with the approved methodology, which allows comparing water quality of separate areas of water objects of different regions. The calculation of the environmental assessment of water quality has been carried according to three blocks: block of salt composition, block of trophic and saprobic (ecological and sanitary) indicators and block of indicators of content of specific toxic substances. The results are presented in the form of a combined environmental assessment, based on the final conclusions of the three blocks and consists in calculating the integral ecological index. Comprehensive studies of changes in the water quality of the Western Bug River have been conducted within the territory of Ukraine for a long-term period. The water quality of the river on the final values of the integral indicators of the ecological condition corresponded mainly to 4nd category of the 3rd class – the water is “satisfactory” by condition and “little polluted” by degree of purity (except for points of observation that located within the Volyn region, where the water quality corresponded to 3rd category and the 2nd class. It is “good” by condition and “fairly clean” by the degree of purity). Visualization and part of the analysis are performed using GIS technologies in the software of the ArcGIS 10.3.

Open access
Effectivity test of an eco-friendly sediment trap model as a strategy to control erosion on agricultural land

Abstract

A sediment trap with bamboo materials can be utilized as one alternative of eco-friendly technology to reduce the erosion that occurred on agricultural land. This study aims to determine the most efficient form of that sediment trap in the field. Location study is in the Tulungrejo Village, Batu, Indonesia, which has andosol soil type and 35 cases of a landslide in 2013. Three forms of sediment traps were used (square, trapezoidal, and stratified type) with the purpose to find the most effective form. It is obtained that the most effective sediment trap is a stratified form with the 31.91% effectiveness or able to withstand sediment of 25.02 kg, while the adequate number is two pieces with the ability to withstand the most considerable sediment of (91.70%). Therefore this stratified form of sediment traps is effective in erosion prevention on agricultural land in the study area. For further development, it is required to test out the variations of the contents in a broader area with a more varied level of the slope.

Open access
Effects of irrigation performance on water balance: Krueng Baro Irrigation Scheme (Aceh-Indonesia) as a case study

Abstract

Krueng Baro Irrigation is focused on increasing the productivity of food crops in Pidie District, Aceh Province, Indonesia. However, due to the age of the irrigation infrastructure (more than 30 years) and its large networks, it is necessary to investigate the actual water conveyance efficiency. This study aimed to evaluate the conveyance efficiency of primary and secondary channels of the irrigation system, as well as to create a water balance model based on the actual water conveyance efficiency. The model by using Excel Solver with its objective function is to maximize the area of the irrigated land. Based on the optimization model of the water balance, the design condition can irrigate an area of 9,496 ha (paddy-I), 4,818 ha (paddy-II), and 11,950 ha (onion). The measurement results reported that the actual efficiency of Baro Kanan and Baro Kiri was 56% and 48% smaller compared to the efficiency of the designs (65%). The water loss was due to the damage to the channel lining and channel erosion resulting in the high sedimentation, leakage, and illegal water tapping. These lead to a decrease in the area of the irrigated land. Based on the optimization model of the actual water balance, the irrigated land was reduced to 7,876 ha (paddy I) and 3,997 ha (paddy-II) while it remained the same for onion. Therefore, to increase the efficiency, the regular maintenance and operations are required by fixing the damaged irrigation structure and channels, the maintenance of sedimentation, and the strict regulation of illegal water tapping.

Open access
Experimental versus theoretical study of reverse osmosis pilot scaling: The case of Algerian brackish water desalination

Abstract

In recent years, the increasing threat to ground water quality due to human activities has become a matter of great concern. The ground water quality problems present today are caused by contamination and by over exploitation or by combination of both. Reverse osmosis (RO) desalination is one of the main technologies for producing fresh water from sea water and brackish ground water.

Algeria is one of the countries which suffer from the water shortage since many years, so desalination technology becomes inevitable solution to this matter.

In this study, a comparison is provided of results of reverse osmosis desalination for three different qualities of brackish water from the central-east region of Algeria (Bouira and Setif Prefectures), wherein they cannot use it as human drinking or in irrigation systems. The main objective of our study is to establish a comparison of the reverse osmosis membrane TW30-2540 performances in the term of (permeate flow, recovery rate, permeate total dissolved solids – TDS and salts rejection) under different operation pressures (each one takes a time of 720 second for pilot scaling). In order to make an overview comparison between the experimental and the simulated results we used ROSA (Reverse Osmosis System Analysis) software.

At the end of this study we noted that, the simulated results are lower than the pilot scaling values and the most removed salts are the sodium chlorides with 99.05% of rejection rate.

Open access
Faecal contamination of water in the Lake Mellah and its catchment area, north-eastern Algeria

Abstract

Lake Mellah close to the Mediterranean Sea in north-eastern Algeria belongs to valuable ornithological sites with numerous, often migratory, birds. To achieve the research goal, seventeen (17) sampling points were sampled based on the urbanization of the watershed. Water samples were taken at different wadis levels (upstream and downstream of settlements), as well as at the wastewater treatment plant and in Lake Mellah based on four measurement campaigns conducted at one frequency seasonal (high water, low water) during the year (2011/2012). Biological parameters (coliform faecal bacteria, streptococci) were analysed in water of the lake and its affluents in the laboratory of the Department of Health and Population, El Taref by the most probable number (MPN) technique of the Mac Grady table taken from various points. Obtained results were processed by the use of Bourgeois ratio (coliform faecal bacteria: streptococci) to indicate the origin of faecal contamination of waters and to establish maps of the spatio-temporal evolution of this ratio by the software Surfer 9. This way we obtained information of contamination of human origin during the dry season coming from domestic waste waters. In winter the ratio showed animal prevalence of contamination coming primarily from Animal Park in El Kala.

Open access
Free surface profile and inception point as characteristics of aerated flow over stepped spillway: Numerical study

Abstract

Stepped spillway is hydraulic structure designed to dissipate the excess in kinetic energy at the downstream of dams and can reduce the size of stilling basin at the toe of the spillway or chute. The flow on a stepped spillway is characterised by the large aeration that can prevent or reduce the cavitation damage. The air entrainment starts where the boundary layer attains the free surface of flow; this point is called “point of inception”. Within this work the inception point is determined by using software Ansys Fluent where the volume of fluid (VOF) model is used as a tool to track the free surface thereby the turbulence closure is derived in the kε turbulence standard model. This research aims to find new formulas for describe the variation of water depth at step edge and the positions of the inception point, at the same time the contour map of velocity, turbulent kinetic energy and strain rate are presented. The found numerical results agree well with experimental results like the values of computed and measured water depth at the inception point and the numerical and experimental inception point locations. Also, the dimensionless water depth profile obtained by numerical method agrees well with that of measurement. This study confirmed that the Ansys Fluent is a robust software for simulating air entrainment and exploring more characteristics of flow over stepped spillways.

Open access
Influence of discharged industrial effluents on the parameters of surface water in Onitsha urban area, southeastern Nigeria

Abstract

Chemical industries in Onitsha urban area of southeastern Nigeria have been discharging large quantities of effluents into surface streams. These streams are the primary sources of water used by poor households for domestic purposes. This study examines the effects of effluents on the physicochemical and microbiological characteristics of the recipient streams. This objective was achieved by collecting eight effluents and twenty-two water samples from control points, discharge locations and exit chutes of the effluents for analysis. The results of the study characterised the effluents and their effects on the recipient streams. The effluents cause gross pollution of the streams as most of the parameters including pH, total dissolved solids (TDS), turbidity, biological oxygen demand (BOD), chemical oxygen demand (COD), Mg, NO3, Fe, Cu, Pb, Cr, total heterotrophic count (THC) and total coliform group (TCG) returned high values that exceeded the World Health Organisation’s (WHO) benchmark from 2011 for drinking water quality. Only dissolved oxygen (DO), Na, Zn, Ca, and Na returned values lower than the WHO guideline. E. coli was found in all the samples; TCG was also high. This paper, therefore, recommends that the effluent generating industries should treat their effluents before disposal.

Open access