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Air or its English equivalent 'water' is very important in our everyday life so much so that when the tap runs dry, it even made it as one of the topics debated by politicians. This paper looks at the issues that surround air/water in Malaysian Parliamentary debates by specifically focusing its relation to the state of Selangor. The air/water related issues were examined based on the collocates of air and Selangor in the Malaysian Hansard Corpus (MHC) from Parliament 1 (P1) to Parliament 13 (P13). The findings show that air is consistently present as one of the collocates of Selangor from Parliament 4 (P4) to Parliament 13 (P13). However, air started to show an upward trend starting in Parliament 7 (P7) and continued to Parliament 13 (P13). The recurring issues during those periods are the never-ending water-related problems and the steps taken by the government to overcome the problems. In P7 and P8, the focus is on the source of water as it collocates with pembersihan logi air (water treatment plant) and kawasan tadahan air (water catchment area). In Parliament 10, Parliament 11, Parliament 12 and Parliament 13 the recurring issue with air and Selangor is penyaluran air mentah (the transfer of raw water) from the neighbouring state Pahang to Selangor. Another issue observed is penstrukturan air (restructuring) of water supply and services which was first observed in Parliament 12 and continues to Parliament 13. Thus, by focusing on the collocates of air this corpus-driven account has managed to show the trend of the parliamentary debates in relation to air and Selangor. Therefore, parliamentary debates where various issues of national interest are often raised offer opportunities for more critical analysis of issues that are important to the public. [ABSTRACT FROM AUTHOR]

Tropical rivers and wetlands are recognized as one of the greatest and most abundant ecosystems in terms of ecological and social benefits. However, climate change, damming, overfishing, water pollution, and the introduction of exotic species threaten these ecosystems, which puts about 65% of river flow and aquatic ecosystems under a moderate to high level of threat. This paper aims to assess the environmental flow of the Selangor River based on the hydrological index method using the Global Environmental Flow Calculator (GEFC) and Indicators of Hydrological Alterations (IHA) software. The daily flow data collected by the Department of Irrigation and Drainage (DID), Malaysia, over a 60-year period (1960–2020) was used in this study to assess the Selangor River flow alterations. As per the results, the river flow has had two distinct periods over the last 60 years. In the first period, the river flows without any alteration and has a natural flow with high flood pulses and low flow pulses. While in the second, or post-impact, period, the flow of the river has a steady condition throughout the year with very little fluctuations between the dry and wet seasons of the year. From the overall comparison of the pre- and post-impact periods, it can be concluded that the minimum flow in the dry seasons of the year has increased, while the maximum flow has decreased in the monsoon seasons during the post-impact period. As a result, the Flow Duration Curve (FDC) and Environmental Management Class (EMC) analysis of the river flow recommends that the Selangor River be managed under EMC "C" to provide sufficient water for both human use and ecosystem conservation, which would also help to avoid a water level drop in the reservoirs. However, further holistic studies are suggested for a detailed analysis of the effects of the dams on aquatic biodiversity and ecosystem services in the Selangor River Basin. [ABSTRACT FROM AUTHOR]

Microplastic pollution has received growing interest due to its persistence and detrimental effects on humans and aquatic organisms. While microplastics in marine sediment have received a lot of attention, microplastics in riverine sediment, particularly in river basins, remain scarce. Therefore, sediment sample was collected from 25 sampling points along the Selangor River Basin and its urbanized tributaries. Microplastics were observed and identified using stereomicroscope and Fourier transform infrared spectroscopy with attenuated total reflection (FTIR-ATR). The results indicated that microplastics were present in all sediment samples, with concentrations ranging from 10 to 55 particles/kg. Small microplastics (< 300 μm) dominated more than half of all microplastics observed, with black color and bead-shaped being the most common characteristic. Polypropylene, polyester, and polyethylene were the primary polymer compositions of the microplastics. The findings suggest that anthropogenic activities from residential, agricultural, and industrial sources may contribute to the ubiquity of microplastics in river. These results highlight the need for further monitoring assessment and proactive measures to mitigate microplastic pollution in riverine environments. [ABSTRACT FROM AUTHOR]

Landslides are a natural hazard that can endanger human life and cause severe environmental damage. A landslide susceptibility map is essential for planning, managing, and preventing landslides occurrences to minimize losses. A variety of techniques are employed to map landslide susceptibility; however, their capability differs depending on the studies. The aim of the research is to produce a landslide susceptibility map for the Langat River Basin in Selangor, Malaysia, using an Artificial Neural Network (ANN). A landslide inventory map contained a total of 140 landslide locations which were randomly separated into training and testing with ratio 70:30. Nine landslide conditioning factors were selected as model input, including: elevation, slope, aspect, curvature, Topographic Wetness Index (TWI), distance to road, distance to river, lithology, and rainfall. The area under the curve (AUC) and several statistical measures of analyses (sensitivity, specificity, accuracy, positive predictive value, and negative predictive value) were used to validate the landslide predictive model. The ANN predictive model was considered and achieved very good results on validation assessment, with an AUC value of 0.940 for both training and testing datasets. This study found rainfall to be the most crucial factor affecting landslide occurrence in the Langat River Basin, with a 0.248 weight index, followed by distance to road (0.200) and elevation (0.136). The results showed that the most susceptible area is located in the north-east of the Langat River Basin. This map might be useful for development planning and management to prevent landslide occurrences in Langat River Basin. [ABSTRACT FROM AUTHOR]

Rapid urbanization in the state of Selangor, Malaysia, has led to a change in the land use, physical properties of basins, vegetation cover and impermeable surface water. These changes have affected the pattern and processes of the hydrological cycle, resulting in the ability of the basin region to store water supply to decline. Reliability on water supply from river basins depends on their low-flow characteristics. The impacts of minimum storage on hydrological drought are yet to be incorporated and assessed. Thus, this study aims to understand the concept of low-flow drought characteristics and the predictive significance of river storage draft rates in managing sustainable water catchment. In this study, the long-term streamflow data of 40 years from seven stations in Selangor were used, and the streamflow trends were analyzed. Low-flow frequency analysis was derived using the Weibull plotting position and four specific frequency distributions. Maximum likelihood was used to parameterize, while Kolmogorov–Smirnov tests were used to evaluate their fit to the dataset. The mass curve was used to quantify the minimum storage draft rate required to maintain the 50 % mean annual flow for the 10-year recurrence interval of low flow. Next, low-flow river discharges were analyzed using the 7 d mean annual minimum, while the drought event was determined using the 90th percentile (Q90) as the threshold level. The inter-event time and moving average was employed to remove the dependent and minor droughts in determining the drought characteristics. The result of the study shows that the lognormal (2P) distribution was found to be the best fit for low-flow frequency analysis to derive the low-flow return period. This analysis reveals September to December to be a critical period in river water storage to sustain the water availability during low flow in a 10-year occurrence interval. These findings indicated that hydrological droughts have generally become more critical in the availability of rivers to sustain water demand during low flows. These results can help in emphasizing the natural flow of water to provide water supply for continuous use during low flow. [ABSTRACT FROM AUTHOR]

The water of Langat River is not suitable for drinking without treatment because of chemical pollution from both the point and non-point pollution sources, although it is one of the primary sources of drinking water in Selangor state, Malaysia. There is no significant study in Malaysia that has investigated the efficiency of treatment plants to remove metals from treated water. Therefore, Chelex 100 resin-ion exchanged method was applied to investigate the raw water samples and treated water samples of eight treatment plants. Samples were analyzed by Inductive Coupled Plasma-Mass Spectrometry for the dissolved concentrations of aluminium, arsenic, cadmium, chromium, and lead, which have complied with the drinking water quality standard of Ministry of Health Malaysia and World Health Organization. However, the average metal removal efficiency is about 52.48 ± 8.89% from treated water by the treatment plants based on a single sampling and this could be considered a preliminary indication to upgrade the treatment technology in Malaysia, because the efficiency in removing trace metals by the plants may vary in hourly samplings. [ABSTRACT FROM AUTHOR]

Seawater intrusion is threatening freshwater resources in coastal regions worldwide. Modelling this phenomenon can help in the management and control of such problems. This study presents a numerical model of seawater intrusion in a semi-confined aquifer in the lowland area of the Langat basin, Selangor, Malaysia, where groundwater is the only source of water supply for mega industrial projects. To provide useful measures for protecting groundwater from pollution by seawater intrusion, a three-dimensional numerical model, Seawat-2000, was applied. The numerical model incorporates regional geological, geographical, and hydrogeological features. The input parameters to the model were determined from well logs, well drillers' reports, and pumping tests. After the model was calibrated using data for the year 2010, the model was used to predict the extent of seawater intrusion for the future (2011-2045) assuming that the current condition of the Langat basin remains unchanged. The results show that the aquifer in the study area will be significantly influenced by seawater intrusion for the next 35 years. [ABSTRACT FROM AUTHOR]

Increasing urbanization and changes in land use in Langat river basin lead to adverse impacts on the environment compartment. One of the major challenges is in identifying sources of organic contaminants. This study presented the application of selected chemometric techniques: cluster analysis (CA), discriminant analysis (DA), and principal component analysis (PCA) to classify the pollution sources in Langat river basin based on the analysis of water and sediment samples collected from 24 stations, monitored for 14 organic contaminants from polycyclic aromatic hydrocarbons (PAHs), sterols, and pesticides groups. The CA and DA enabled to group 24 monitoring sites into three groups of pollution source (industry and urban socioeconomic, agricultural activity, and urban/domestic sewage) with five major discriminating variables: naphthalene, pyrene, benzo[a]pyrene, coprostanol, and cholesterol. PCA analysis, applied to water data sets, resulted in four latent factors explaining 79.0% of the total variance while sediment samples gave five latent factors with 77.6% explained variance. The varifactors (VFs) obtained from PCA indicated that sterols (coprostanol, cholesterol, stigmasterol, β-sitosterol, and stigmastanol) are strongly correlated to domestic and urban sewage, PAHs (naphthalene, acenaphthene, pyrene, benzo[a]anthracene, and benzo[a]pyrene) from industrial and urban activities and chlorpyrifos correlated to samples nearby agricultural sites. The results demonstrated that chemometric techniques can be used for rapid assessment of water and sediment contaminations. [ABSTRACT FROM AUTHOR]

Surface sediments were collected from 11 sampling sites in selected intertidals and drainages of Selangor. The sediment samples were analysed for Ni and Zn. The metal concentrations ranged from 15.1 to 121 μg/g dry weight for Ni and 50.2 to 336 μg/g dry weight for Zn. The highest total (Ni and Zn) concentrations in sediments were found at an industrial site in Serdang. The Ni and Zn ranges resulting from this study were wider and higher than those reported previously in Malaysia. Generally, the 'oxidisable-organic' fraction contributed the largest percentage of metals among the other three anthropogenic-related fractions. This study shows that the non-resistant fraction dominated the total Zn based on sequential extraction technique. Some sites had higher percentage (>50%) of non-resistant fraction of Ni and Zn, indicating anthropogenic sources of these metals. Therefore, it is suggested that continuous monitoring of the study areas be implemented especially at industrial areas in Serdang. Perhaps, the industrial waste must be treated before draining to the waterways. [ABSTRACT FROM AUTHOR]

Conservative peak flood discharge estimation methods such as the rational method do not take into account the soil infiltration of the precipitation, thus leading to inaccurate estimations of peak discharges during storm events. The accuracy of estimated peak flood discharge is crucial in designing a drainage system that has the capacity to channel runoffs during a storm event, especially cloudbursts and in the analysis of flood prevention and mitigation. The aim of this study was to model the peak flood discharges of each sub-watershed in Selangor using a geographic information system (GIS). The geospatial modelling integrated the watershed terrain model, the developed Soil Conservation Service Curve Cumber (SCS-CN) and precipitation to develop an equation for estimation of peak flood discharge. Hydrological Engineering Center-Hydrological Modeling System (HEC-HMS) was used again to simulate the rainfall-runoff based on the Clark-unit hydrograph to validate the modelled estimation of peak flood discharge. The estimated peak flood discharge showed a coefficient of determination, r2 of 0.9445, when compared with the runoff simulation of the Clark-unit hydrograph. Both the results of the geospatial modelling and the developed equation suggest that the peak flood discharge of a sub-watershed during a storm event has a positive relationship with the watershed area, precipitation and Curve Number (CN), which takes into account the soil bulk density and land-use of the studied area, Selangor in Malaysia. The findings of the study present a comparable and holistic approach to the estimation of peak flood discharge in a watershed which can be in the absence of a hydrodynamic simulation model. [ABSTRACT FROM AUTHOR]