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Number of results: 18
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Abstract

Lake Mellah close to the Mediterranean Sea in north-eastern Algeria belongs to valuable ornithological sites with nu-merous, 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 settle-ments), 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 bac-teria, 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. Ob-tained results were processed by the use of Bourgeois ratio (coliform faecal bacteria: streptococci) to indicate the origin offaecal 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.

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Authors and Affiliations

Wahida Kherifi
Lynda Hecini
Fedia Bekiri
Houria Kherici-Bousnoubra
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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 mgꞏdm–3, with 78% of samples exceeding the critical level value set at 50 mgꞏdm–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 mgꞏdm–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 CFUꞏ(100 cm3)–1 respectively, con-firming 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.

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Mohammed Kadaoui
Abderrahime Bouali
Mourad Arabi
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Abstract

Solar radiation (Rs) is an essential input for estimating reference crop evapotranspiration, ETo. An accurate estimate of ETo is the first step involved in determining water demand of field crops. The objective of this study was to assess the ac-curacy of fifteen empirical solar radiations (Rs) models and determine its effects on ETo estimates for three sites in humid tropical environment (Abakaliki, Nsukka, and Awka). Meteorological data from the archives of NASA (from 1983 to 2005) was used to derive empirical constants (calibration) for the different models at each location while data from 2006 to 2015 was used for validation. The results showed an overall improvement when comparing measured Rs with Rs determined us-ing original constants and Rs using the new constants. After calibration, the Swartman–Ogunlade (R2 = 0.97) and Chen 2 models (RMSE = 0.665 MJ∙m–2∙day–1) performed best while Chen 1 (R2 = 0.66) and Bristow–Campbell models (RMSE = 1.58 MJ∙m–2∙day–1) performed least in estimating Rs in Abakaliki. At the Nsukka station, Swartman–Ogunlade (R2 = 0.96) and Adeala models (RMSE = 0.785 MJ∙m–2∙day–1) performed best while Hargreaves–Samani (R2 = 0.64) and Chen 1 mod-els (RMSE = 1.96 MJ∙m–2∙day–1) performed least in estimating Rs. Chen 2 (R2 = 0.98) and Swartman–Ogunlade models (RMSE = 0.43 MJ∙m–2∙day–1) performed best while Hargreaves–Samani (R2 = 0.68) and Chen 1 models (RMSE = 1.64 MJ∙m–2∙day–1) performed least in estimating Rs in Awka. For estimating ETo, Adeala (R2 =0.98) and Swartman–Ogunlade models (RMSE = 0.064 MJ∙m–2∙day–1) performed best at the Awka station and Swartman–Ogunlade (R2 = 0.98) and Chen 2 models (RMSE = 0.43 MJ∙m–2∙day–1) performed best at Abakaliki while Angstrom–Prescott–Page (R2 = 0.96) and El-Sebaii models (RMSE = 0.0908 mm∙day–1) performed best at the Nsukka station.

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Emeka Ndulue
Ikenna Onyekwelu
Kingsley Nnaemeka Ogbu
Vintus Ogwo
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Abstract

The occurrence of a hydraulic connection between piezometers is identified based on similar changes in water levels. Some piezometers react to changing upper or lower water levels, some may also react to atmospheric precipitation. If the reaction to variable upper water levels is significant, then leakage of seepage control devices is identified and the dam is subjected to repair works. The aim of this research paper is to present and analyse the dynamics of variability of water lev-els in open piezometers of the Chańcza dam, located at the 36 km of the Czarna Staszowska River in the town of Korytnica in Świętokrzyskie province (Poland). Before the analysis of the piezometric data was commenced, the Grubbs statistical test was used to identify and reject the outliers. The scope of the research includes the data captured between January 14, 2014 and January 13, 2017. A hypothesis was formulated that the change in the trend occurred after the spring of 2015 when the water level in the reservoir was reduced by approx. 1.5 m. Two trend lines were adapted for the water levels of each pie-zometer using the least squares method – the first one for the period from January 2014 to May 2015, and the second one from June 2015 to January 2017. In this way, two slopes of the linear function were obtained together with an estimation of their errors. These slopes were compared using a statistical parallelism test.

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Authors and Affiliations

Stanisław K. Lach
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Abstract

Rural development policy of Agricultural Property Stock (APS) of the State Treasury in Poland is run by the National Support Centre for Agriculture (until 31.08.2017 Agricultural Property Agency). In the article, on the example of the Braniewo municipality, the size and spatial distribution of land transferred from the Agricultural Property Stock (APS) of the State Treasury to the municipality was analysed. One of the most important goals associated with this was activities related to social aspects, often part of the revitalization and renewal of the rural areas. After Poland's accession to the Euro-pean Union, it was possible to obtain subsidies that allowed the rural population to apply for financing projects, such as: road construction, creating school playgrounds or socio-cultural facilities. Authors also analysed examples of good practic-es in this area in the municipality of Braniewo, as a recommendation for other municipalities. Attempts have also been made to indicate the role of the National Support Centre for Agriculture in the transformation of the Polish countryside, with particular emphasis on the areas of former State Agricultural Farms.

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Authors and Affiliations

Marek P. Ogryzek
Krzysztof Rząsa
Mateusz Ciski
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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 lo-cations 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 dis-solved 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, there-fore, recommends that the effluent generating industries should treat their effluents before disposal.

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Authors and Affiliations

Michael C. Obeta
Uchenna P. Okafor
Cletus F. Nwankwo
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Abstract

The selected techniques were reviewed and their technological aspects were characterized in the context of multi-phase flow for biogas production. The conditions of anaerobic fermentation for pig slurry in a mono-substrate reactor with skele-ton bed were analysed. The required technical and technological criteria for producing raw biogas were indicated.

Design and construction of the mono-substrate model, biogas flow reactor, developed for cooperation with livestock buildings of various sizes and power from 2.5 kW to 40 kW. The installation has the form of a sealed fermentation tank filled with a skeletal deposit constituting a peculiar spatial system with regular shapes and a rough surface.

Incorporating a plant in such a production cycle that enables the entire slurry stream to be directed from the cowshed or pig house underrun channels to the reactor operating in the flow mode, where anaerobic digestion will take place, allows to obtain a biogas.

The paper presents preliminary results of experimental investigations in the field of hydrodynamic substrate mixing system for biogas flow assessment by the adhesive bed in the context of biogas production. The aim of the study was to assessment and shows the influence of the Reynolds number on the biogas resistance factor for the fermentation process in mono-substrate reactor with adhesive deposit. The measurement results indicate a clear effect of the Reynolds number in relation to the descending flow resistance coefficient for the adhesive bed.

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Authors and Affiliations

Grzegorz Wałowski
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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 characterisedby 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 k – ε turbulence standard model. This research aims to find new formulas for de-scribe the variation of water depth at step edge and the positions of the inception point, at the same time the contour map ofvelocity, 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 explor-ing more characteristics of flow over stepped spillways.

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Authors and Affiliations

Chakib Bentalha
Mohammed Habi
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Abstract

Water quality is an important criterion for evaluating the suitability of water for drinking and domestic purpose. The main objective of this study was to investigate the physicochemical characterization of groundwater for drinking water con-sumption. Ten captured sources were selected from three aquifers including the Guelma Mio-Plio-Quaternary alluvial ba-sin; the Senonian Heliopolis Neritic limestone aquifer, and the Eocene limestones of Ras El Agba-Sellaoua aquifer. The analyses concerned the periods of high water in May 2017 and low water in August 2017. Twelve parameters were deter-mined for the water samples: pH, T (°C), EC, Ca2+, Mg2+, Na+, K+, Cl–, HCO3–, SO42–, NO3–, TH (hydrotimetric degree), TAT (total alkalinity titration). The interpretation of the various analytical results allowed the determination of the chemical facies and the classification of the groundwater aquifers as follows: (i) in the alluvial layer, the gypsiferous marl substratum and the clays of the three terraces (high, medium and low) have given the water a chlorinated calcium chemical facies in the east part of the study area and travertines feeding partly alluvial layer, and have given a bicarbonated calcium water facies in the west, (ii) in the Senonian of Heliopolis limestone and Eocene carbonate formations of Ras El Agba- -Sellaoua, the chemical facies are calcium bicarbonate. Water isotopes (δ18O and δD) helped to determine the origin of groundwater. Overall, the groundwater in the area is hard and has significant to excessive mineralization. It is progressivelydegraded in the direction of flow, especially in the Guelma alluvial aquifer.

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Authors and Affiliations

Kaddour Benmarce
Kamel Khanchoul
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Abstract

This study presents the spatial variability and dynamics of soil organic carbon (SOC), soil organic matter (SOM) and soil pH contents at the Wonji Shoa Sugar Estate (WSSE), Ethiopia. Soil samples were collected immediately after the sug-arcane was harvested and then analysed for SOC, SOM and pH content using standard procedures. The analysis resultsshowed that the pH value varied between 6.7–8.4 (neutral to moderately alkaline) and 7.3–8.5 (neutral to strongly alkaline) for the top and bottom soil profiles, respectively. The SOM content is in the range of 1.1–6.7% and 0.74–3.3% for the upper and lower soil layers, respectively. Nearly 45% of the samples demonstrated a SOM content below the desirable threshold (<2.1%) in the bottom layer and, hence, inadequate. Moreover, most of the topsoil layer (95%) has an SOM content exceed-ing the desirable limit and hence is categorized within the normal range. Interestingly, the SOC content showed a spatial variability in both the surface and sub-surface soil layers. A lower SOC and SOM content was found for the sub-soil in the south and southwestern part of the plantation. A further decline in the SOC and SOM content may face the estate if the cur-rent waterlogging condition continues in the future for a long period. Overall, the study result emphasizes the need to min-imize the pre-harvest burning of sugarcane and action is needed to change the irrigation method to green harvesting to fa-cilitate the SOC retention in the soil and minimize the greenhouse emission effect on the environment, hence improving soil quality in the long-term.

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Authors and Affiliations

Megersa Olumana Dinka
Meseret Dawit
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Abstract

In recent years, the increasing threat to ground water quality due to human activities has become a matter of great con-cern. 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 brack-ish water from the central-east region of Algeria (Bouira and Setif Prefectures), wherein they cannot use it as human drink-ing 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 re-jection) 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 Analy-sis) software.

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

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Authors and Affiliations

Abderrezak Bouchareb
Mehdi Metaiche
Hakim Lounici
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Abstract

Typhoid or enteric fever is a worldwide infection caused by the bacterium Salmonella enterica. In Sri Lanka, 12,823 Salmonella positive cases were recorded and 133 cases were recorded from Anuradhapura district during 2005 to 2014. Therefore, the study was carried out to identify the microbiological and chemical contamination status of forty-four water sources in Anuradhapura area during October 2016. The study was focused to determine total coliform, faecal coliform, Salmonella spp. and Shigella spp. contamination along with some physico-chemical parameters of both ground and surface water. Sampling, transportation, and analysis were performed following standard protocols. Results of the study revealed that almost all sampling locations were contaminated with both total and E. coli bacteria and the values were not within the World Health Organization and Sri Lanka Standards drinking water quality standards. Around 32% of sampling locations were positive for Salmonella spp. and among them, 2 spring sampling locations are being highly used to extract water for drinking. However, Shigella spp. was not recorded during the study period. Majority of the sampling points were not within the Sri Lanka drinking water standards for COD and 25% sampling locations were recorded greater than 750 μS∙cm–1 con-ductivity. Also, 55% of locations recorded very hard water where the highest values were recorded in Padaviya. The tested other water quality parameters: NO2-N, NH3-N, and total phosphate (TP) concentrations were found within the Sri Lanka drinking water standards. PCA analysis revealed that sampling locations were grouped into three groups such as; well wa-ter, tank water and springs.

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Authors and Affiliations

M.G.Y.L. Mahagamage
Pathmalal M. Manage
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Abstract

During the last few years, the City of Bechar in Algeria has witnessed some extreme events, such as the great flood of the year 2008 in which an exceptional amount of rain was recorded with a flow rate of 830 m3∙s–1 (hwater = 4 m, b = 200 m); similar flooding also occurred in 2012 and 2014. The problem is that most of the City of Bechar has an urban sprawl that extends to the banks of Wadi Bechar, which represents a huge risk for the lives of the inhabitants of the region. The present work aims to assess the flood risk through flood hazard mapping. This method consists in determining the flow rates for the return periods of 25 years (Q25 = 388.6 m3∙s–1, hwater = 3.5 m, b = 200 m, Sspot = 55.35 ha), 50 years (Q50 = 478.3 m3∙s–1, hwater = 5 m, b = 200 m, Sspot = 66.48 ha) and 100 years (Q100 = 567.3 m3∙s–1, hwater = 7 m, b = 200 m, Sspot = 133 ha). For this, it is necessary to adjust the flow rates using Gumbel law along with some computer supports such as HEC-RAS, HEC- -GeoRAS and ArcGis for mapping the event. Finally, this work enables us to determine the zones exposed to risk of flooding and to classify them according to the flood water height.

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Authors and Affiliations

Abdelghani Bekhira
Mohammed Habi
Boutkhil Morsli
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Abstract

Krueng Baro Irrigation is focused on increasing the productivity of food crops in Pidie District, Aceh Province, Indo-nesia. 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 convey-ance 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.

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Authors and Affiliations

Azmeri Azmeri
Alfiansyah Yulianur
Uli Zahrati
Imam Faudli
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Abstract

A sediment trap with bamboo materials can be utilized as one alternative of eco-friendly technology to reduce the ero-sion 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 consider-able sediment of (91.70%). Therefore this stratified form of sediment traps is effective in erosion prevention on agriculturalland 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.

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Authors and Affiliations

Riyanto Haribowo
Ussy Andawayanti
Rahmah Dara Lufira
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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 as-sessment of water quality has been carried according to three blocks: block of salt composition, block of trophic and sapro-bic (ecological and sanitary) indicators and block of indicators of content of specific toxic substances. The results are pre-sented 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 Riv-er 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 wa-ter 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.

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Authors and Affiliations

Igor Gopchak
Tetiana Basiuk
Ihor Bialyk
Oleg Pinchuk
Ievgenii Gerasimov
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Abstract

Based on chemical analyses, the quality of ground waters for drinking, agricultural and industrial purposes was deter-mined 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 corro-sive 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.

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Authors and Affiliations

Mohammad Hossein Jahangir
Keyvan Soltani
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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), anthropogen-ic 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.

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Authors and Affiliations

Ang Kean Hua

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