470 research outputs found

    Predicting and simulating future land use pattern : a case study of Seremban district

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    As long as rapid urbanization which is a result of natural population growth and rural urban migration due to push and pull factors of social and economic conditions as well as the moving of urban populations from major city centres to urban fringe areas due to changing lifestyle which emphasized on spacious and more comfortable and environmentally friendly living environment continue to happen; towns and cities will continue to grow and expand to accommodate the growing and complex demand of the people. Experiences have shown that rapid and uncontrolled expansion of towns and cities has led to amongst others the deterioration in the quality of urban environment and sprawling of urban development onto prime agricultural and forest areas as well as cities starting to lose their identity. In order to avoid such phenomena continuing to happen, particularly in the Kuala Lumpur Conurbation Area, towns and cities need to be properly planned and managed so that their growth or expansion can be controlled and managed in a sustainable manner. One of the strategies adopted to curb sprawling development is through the delineation of urban growth or development limits (UGL). This means that the limit of towns and cities need to be studied and identified, so that urban development can be directed to areas that are identified and specified suitable for such development. One of the main tasks in the process of delineating UGL has been included as an important task in the preparation of development plans. With such policy a research study is now being carried out to develop a spatial modelling framework towards delineating UGL through the application and integration of spatial technologies and this will be a basis or framework for land use planners, managers and policy makers to formulate urban land use policies and monitor urban land use development. One of the main analysis involve in the process of performing this task is to understand past urban land development trend and to predict and identify future urban growth areas of the selected study area. This paper highlights the integration of statistical modeling technique via binary logistic regression analysis with GIS technology in understanding and predicting urban growth pattern and area as applied to District of Seremban, Negeri Sembilan. The result shows that urban land use pattern in the study area within the study period are significantly related to more than half of the predictors used in the analysis

    Behaviours of natural organic matter in membrane filtration for surface water treatment : a review

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    Membrane application in surface water treatment provides many advantages over conventional treatment. However, this effort is hampered by the fouling issue, which restricts its widespread application due to increases in hydraulic resistances, operational and maintenance costs, deterioration of productivity and frequency of membrane regeneration problems. This paper discusses natural organic matter (NOM) and its components as the major membrane foulants that occur during the water filtration process, possible fouling mechanisms relating to reversible and irreversible of NOM fouling, current techniques used to characterize fouling mechanisms and methods to control fouling. Feed properties, membrane characteristics, operational conditions and solution chemistry were also found to strongly influence the nature and extent of NOM fouling. Findings of such studies are highlighted. The understanding of the combined roles of controlling factors and the methods used is very important in order to choose and optimize the best technique and conditions during surface water treatment. The future potential of membrane application for NOM removal is also discussed

    Development of generalized feed forward network for predicting annual flood (depth) of a tropical river

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    The modeling of rainfall-runoff relationship in a watershed is very important in designing hydraulic structures, controlling flood and managing storm water. Artificial Neural Networks (ANNs) are known as having the ability to model nonlinear mechanisms. This study aimed at developing a Generalized Feed Forward (GFF) network model for predicting annual flood (depth) of Johor River in Peninsular Malaysia. In order to avoid over training, cross-validation technique was performed for optimizing the model. In addition, predictive uncertainty index was used to protect of over parameterization. The governing training algorithm was back propagation with momentum term and tangent hyperbolic types was used as transfer function for hidden and output layers. The results showed that the optimum architecture was derived by linear tangent hyperbolic transfer function for both hidden and output layers. The values of Nash and Sutcliffe (NS) and Root mean square error (RMSE) obtained 0.98 and 5.92 for the test period. Cross validation evaluation showed 9 process elements is adequate in hidden layer for optimum generalization by considering the predictive uncertainty index obtained (0.14) for test period which is acceptable

    COMMUNITY LOSS OF RESIDENTIAL VALUE FROM WATER AND NOISE POLLUTION

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    The impact of environmental disamenity on residential value had continued to receive attention in the property market. This study estimates community loss of residential value resulting from water and noise pollutions in the local neighbourhoods. The study areas comprised residential neighbourhoods nearby sources of such pollutions. Upon integration of the digital cadastre and house transaction data, digital maps were used to identify parcels of residential properties that were presumably affected by such pollutions in the study areas. Using the overlay and buffering functions, two proxy environmental variables were included in the regression models to capture pollution effects on residential values. The analysis disclosed that houses located closer to water and noise pollution were sold at lower prices compared to those located farther away from it. The total amount of community loss of “pollution-imposed†residential value in seven selected neighbourhoods was in excess of RM 57 million. The evidence shows that house buyers regard environmental quality as an important factor in real estate transaction. In particular, environmental disamenity resulting from water and noise pollution could have been negatively capitalised into residential values

    Priority ranking of Skudai River sub-watersheds for potential flood damages and water quality parameters

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    Sustainability of a watershed generally depends on climatic, hydrological, environmental, social, economical, ecological and many more other factors. The watersheds in Malaysia generally have two issues, which are water quality degradation and flash floods. Economic development activities have increased many folds in last few decades which have affected many watersheds including Skudai River watershed. In this study, Skudai River watershed was delineated into 25 sub-watersheds (SW) and a sustainability index for the watershed was developed by considering Potential Water Quality Deterioration (PWQD) and Potential Flood Damage (PFD) parameters. In order to get actual or at least close to actual classification of river water, the existing water quality index (WQI) developed by the Department of Environment (DOE) known as DOE-WQI formula was modified by adding six more important water quality parameters, which were total phosphorus, nitrate, total dissolved solids, electrical conductivity, turbidity and temperature. The weights to the water quality parameters in the modified WQI were elicited from 32 water experts in face-to-face survey. The modified WQI produced river water classifications, which were Class II for Skudai River- Natural (SKN) and Skudai River- Head (SKH) sampling points and Class III for Senai River (SEN), Skudai River- Middle (SKM), Skudai River- Tail (SKT), Danga River (DAN), Melana River (MEL) and Kempas River (KEM) sampling points. The weights of watershed sustainability indicators in the Skudai River watershed sustainability index (WSI) were obtained from 30 stakeholders consisted of engineers from various departments. Combining modified WQI and PFD parameters using pressure-state-response (PSR) model resulted in a framework of WSI for the Skudai River watershed. The WSI score for every sub-watershed was calculated by incorporating watershed sustainability indicators data and weights. The final ranking of sub-watersheds was SW2> SW7> SW6> SW1> SW4> SW3> SW5> SW8> SW12> SW18> SW25> SW10 >SW9 > SW14> SW16> SW24> SW17> SW11> SW22> SW19> SW13> SW15> SW21> SW23> SW20

    Modelling the impacts of land-used and climate change in Skudai river watershed

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    Predicting the impact of land-use, climate change and Best Management Practices (BMPs) on a watershed is imperative for effective management of aquatic ecosystems, floods, pollutant control and maintenance of water quality standard in a tropical climate. Based on the prediction, unique information can be derived that is critical to the watershed management under dynamic environmental conditions. The study seeks to evaluate how land-use and climate change influences the hydrology, sediments, and water quality of an urbanized tropical watershed in which the land-use is controlled by urban development as observed from historical and projected land covers. Therefore, the response of a tropica l watershed and its river system under climate and land-use changes were evaluated using Skudai River watershed as a case study. Seven land-use scenarios from the year 1989 to 2039 were developed using remote sensing teclmiques, and nine projected climate change scenarios were derived using dynamically downscaled model from the based projection under representative concentration pathways (RCPs) scenarios. These scenarios were integrated into the Hydrological Simulation Program FORTRAN (HSPF) model to determine the impact of land-use , climate change, and pollutants control via best management practices in a tropical watershed system. The model was calibrated and validated from 2002 to 2014, and the performance coefficients showed a good correlation between simulated and observed streamflow, water temperature, dissolved oxygen (DO), biochemical oxygen demand (BOD), ammonia nitrogen (NH3-N), nitrate nitrogen (N03-N), and orthophosphate (P04) concentrations. The output of the validated model under land-use changes showed that the hydrological water balance of the watershed changes with total runoff as the primary source of water loss. For streamflows and in-stream concentrations (NH3-N, N03-N, and P04) , as the streamflow increases, NH3-N and P04 concentrations increase while N03-N concentration showed low response as compared to the other two concentrations. As urban development increased from 18.2% to 49.2%, nutrient influx such as total nitrogen (TN) and total phosphorus (TP) loads increased from 3080 to 4560 kg/yr and from 130 to 270 kg/yr, respectively. Furthermore, TN to TP ratio changed from 8.3:1 to 7:1, an indication that the rivers are receiving excess nutrients flows which might result in eutrophication at the downstream of the watershed . The amount of sediment load produced in the watershed decreased by approximately 17.8% as a result of the changes in land-use derived from urban development. Further analysis ofthe results showed that climate change with high rainfall and increase in air temperature do not affect DO concentration and water temperature in comparison to climate change with low rainfall. Implementation of multiple detention pond BMPs in identified Critical Source Areas (CSAs) reduced pollutant loads by 14% to 27% as compared to watershed without any BMPS, independent ofclimate and landuse changes. Analysis ofBMPs using existing and future land-use is very important to ensure their effectiveness to control and maintain water quality. This study provides a basis to develop water resource management in an urban watershed and be resilient to land-use and climate changes

    Monitoring and modelling antibiotic resistance in Southeast Asian rivers

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    PhD ThesisPinpointing environmental antibiotic resistance (AR) hotspots in rivers in low-and-middle income countries (LMICs) is hindered by a lack of available and comparable AR monitoring data relevant to such settings. Addressing this problem, a comprehensive spatial and seasonal assessment of water quality and AR conditions in a Malaysian river catchment was preformed to identify potential 'simple' surrogates that mirror elevated AR. This included screening for β-lactam resistant coliforms, 22 antibiotics, 287 AR genes and integrons, and routine water quality parameters, covering absolute concentrations and mass loadings. Novel approaches were developed and applied to advance environmental microbiome and resistome research. To investigate relationships, standardised 'effect sizes' (Cohen's D) were introduced for AR monitoring to improve comparability of field studies. Quantitative microbiome profiling (QMP) was applied to overcome biases caused by relative taxa abundance data. In addition, Hill numbers were introduced as a unified diversity framework for environmental microbiome research. Overall, water quality generally declined, and environmental AR levels increased as one moved downstream the catchment without major seasonal variations, except total antibiotic concentrations that were higher in the dry season (Cohen's D > 0.8, P < 0.05). Among simple surrogates, dissolved oxygen (DO) most strongly correlated (inversely) with total AR gene concentrations (Spearman’s ρ 0.81, P < 0.05). This is suspected to result from minimally treated sewage inputs, which also contain AR bacteria and genes, depleting DO in the most impacted reaches. Thus, although DO is not a measure of AR, relatively lower DO levels reflect wastewater inputs, flagging possible AR hot spots. Furthermore, DO is easy-to-measure and inexpensive, already monitored in many catchments, and exists in many numerical water quality models (e.g., oxygen sag curves). Therefore, combining DO data and prospective modelling (e.g., with the watershed model HSPF) could guide local interventions, especially in LMIC rivers with limited data

    Assessment of emerging pollutants in Skudai river and its treatability at downstream water treatment plant

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    Emerging Pollutants (EPs) are synthetic or naturally occurring compounds currently detected in water environment. These chemicals such as surfactants, pharmaceuticals, personal care products (PCPs) and pesticides could cause adverse ecological and human health effects which include alteration of the normal function of endocrine systems of human and animals. With variation of potential sources, determination of their presence is also a difficult and costly. Different treatment technologies to remove the EPs for drinking water have been studied, which include adsorption, chemical oxidation and membrane filtration. Nevertheless, these technologies are relatively costly in terms of capital, operation and maintenance. This study was carried out to identify the best technique in extracting the EPs from water for screening purposes, to assess their presence in River Skudai and to determine the ability of downstream water treatment plant (WTP) to remove the EPs. Identification approach and solvent was carried out through extensive literature review and trial tests. Samples were taken from eight sampling points in Skudai River and five points in the WTP. Samples were pretreated using solid phase extraction (SPE) method and were analysed using Liquid Chromatography-Mass Spectrometry Detection (LCMSQTOF) for the river water sample and using Gas Chromatography-Mass Spectrometry (GCMS) for the treatment plant water sample. It was surmised that the extraction of EPs is largely based on polarity. The acetonitrile and methanol are highly polar solvents that can achieve high yields of EPs. EPs detected in Skudai River can be categorized into three groups, namely pharmaceutical (decylamine, hexadecyl isocyanate, methotrexate, butirosin A, tridodecylamine and 4-vinylcyclohexene), PCPs (tetradecylamine, limonene, oleylamine, and diethanolamine) and EDCs (styrene, ethylbenzene, phthalic and alfa-methyl styrene). The concentration of styrene ranged from 45 µg/L to 203 µg/L with an increasing trend towards downstream of the river. All the EPs detected are classified as toxic and carcinogenic compounds. As for the WTP, the coagulation process successfully removed endosulfan, chlorothalonil, and ethylbenzene while sedimentation removed 50% of benzene, 50% of triazine, along with 100% of ibuprofen and bisphenol A (BPA). Filtration and chlorination process did not remove styrene or triazine. Trihalomethanes (THMs) which are classified as EDCs were formed after chlorination process. Using polynomial multivariate, the removal rate of triazine in the water treatment plant was modelled. A nonlinear regression design was successfully applied to model the response as a polynomial function based on selected independent. Polynomial multivariate was further used to conduct and evaluate the effectiveness of coagulation and sedimentation process. The findings of this study indicate that different types of EPs can be found in Skudai River. While many can be successfully removed in the conventional water treatment plant, more efforts are needed to ensure that the environment and human health are protected from the hazardous EPs

    Introduction of Pack Test for Participative Environmental Monitoring and Environmental Education for Sustainability in Malaysia

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    Pack Test which provided by Kyoritsu Chemical-Check Lab. Corporation has been assumed as a professional easy-to-use onsite water quality checker. The aim of this study is to examine the possibility of application of Pack Test in Malaysia, and to assess the required matters during introduction processes. Two workshops were sampled to prove the potential function of Pack Test in environmental education and participative environmental monitoring. Two hours lecture of Universiti Teknologi Malaysia (UTM) was facilitated as a workshop by author on September 23, 2010, and then the author has assisted a workshop in Putrajaya on October 9, 2010. Questionnaire forms were applied to test as if peoples feeling are positive or not towards Pack Test as preliminary research. Water quality parameters were simultaneously measured by Pack Test, such as, COD, NO3-, CI-, and NH4+ in UTM, pH and NO3- were measured in Putrajaya workshop, respectively. Participants feeling in the both workshops showed strong positive potential for Pack Test. Results of water qualities from UTM workshop had big variation in COD and NO3-. Considering the reason, the UTM workshop was conducted without proper support for both facilitator and participant. Participants were able to classify the water quality level in a short time. As for the Putrajaya workshop, with deep support and well skilled instruction by facilitator team, the data showed small variation i.e. good and consistent water quality result. It was obvious that Pack Test was always applicable to assess water environment and it was well functioned as user friendly easy-to-use water quality checker. Thereby the role of Pack Test was segregated from conventional standard methods. The participants feeling to Pack Test was strong positive for implementation and to improve public environmental awareness. Simultaneously, they were feeling that peoples can participate more effectively in water environment issues by Pack Test. It was clear that Pack Test was notable in-situ water quality checker, which has advantages over its particular methods that never rely on transport of samples to a distant laboratory for chemical analysis. Above all, it could be a breakthrough point to empower public participation, and environmental education for water sustainability. In addition, it can be pointed out that if there are chance to get skilled of the USAge of Pack Test, which will be important for teachers, engineers, and other potential facilitators to ensure the effective USAge of Pack Test towards

    Estimation of hydrological changes in a tropical watershed using multi-temporal land-use and dynamic modelling

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    The response of a watershed due to changes in its physical environment might result in floods, river erosions and siltations, subsequently affecting humans and biotas. Evaluating land-use changes is crucial for better assessment of hydrological conditions in a watershed system. The remote sensing imagery, field data collection, and land change modelling were used to produce the land-use maps of different spatiotemporal scale from 1989 to 2039. The generated maps are integrated into Hydrological Simulation Program-Fortran (HSPF) model, to evaluate the hydrological changes in Skudai River watershed in Malaysia. Total runoff is expected to account for 57% of the rainfall influx by 2039, a change of 2% from 1989 land-use, an indication of the low response of runoff to change in land-use. As built-up land increase by 3.39%, the average streamflow will increase by 0.05 m3/s. It will further reduce actual evapotranspiration (AET) by 0.39%, groundwater by 0.34% and change in storage by 0.38%. The sensitivity analysis of the hydrological elements to the land-use changes indicates that AET being the most sensitive then change in storage, and total runoff showing the lowest sensitivity. The result of the study provides information on the long-term impact of land-use on the hydrology of the tropical watershed, and it can be a useful tool in the planning and management of a watershed in a different perspective
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