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This paper discussed the use of stable isotope compositions of precipitation (δ2H and δ18O) to understand its characteristics and the parameters controlling meteorological conditions in Malaysia. The meteoric water line for Malaysia, or MMWL established in this study are δ2H = (7.43 ± 0.05)δ18O + (7.33 ± 0.11) (n = 595, r2 = 0.97) for individual values, and δ2H = (7.07 ± 0.20)δ18O + (4.90 ± 0.75) (n = 51, r2 = 0.96) for annual precipitation weighted means. No major variations in local meteoric water lines established between the stations, except for one (i.e., Cameron Highlands), which was found to be significantly different due to its high deuterium excess, or d value, attributed to moisture recycling (re–evapotranspiration) from the surrounding dense rainforest area. The precipitation moisture came from the two monsoon systems; the Northeast monsoon (NEM) and Southwest monsoon (SWM). They differ only slightly in their isotope signatures, where the NEM (winter monsoon) is 0.38‰ more negative than the SWM (summer monsoon), and the rainfall amount and temperature have a relatively weak influence on the stable isotopes in precipitation. Rainfall δ18O is poorly correlated with the monthly rainfall amount and temperature, with very low r2 values (–0.4‰/100 mm; 0.09 and 0.7‰/°C; 0.06, respectively). The seasonal variability of isotopic compositions of precipitation in this region is controlled by the insubstantial but conspicuous inverse correlation amount effect. The seasonal patterns of δ2H and δ18O are evident, with higher values observed during the NEM and lower values observed during SWM. However, the temporal variations of rainfall δ2H and δ18O during NEM and SWM are almost indistinguishable due to local climatic conditions, prevailing atmospheric circulations, and sources of precipitation. The apparent sign of El Niño and La Niña events (2015 and 2017, respectively) of the El Niño–Southern Oscillation (ENSO) cycle were successfully identified from this study, indicated by the heavier δ18O from the peaks in the annual precipitation amount versus δ18O annual precipitation weighted mean plot, while La Niña corresponds to the lighter values of the rainfall isotopes. [ABSTRACT FROM AUTHOR]

In this study, an alternative approach was applied for the characterization of the subsurface geological conditions to estimate the hydrological parameters in the absence of subsurface soil data. The study revealed that the hydrological parameters, estimated from the Transient Electromagnetic (TEM) and Electrical Resistivity Tomography (ERT), were significantly correlated with in situ data. Overall estimated infiltration rate (below 20 inches/h) predicted fine-grained soil was also associated with in situ data. A high correlation among the bulk electrical resistivity, porosity, and the resistivity of the pore fluid thereby confirmed the relevance of Archie's law used in this study. Furthermore, results showed that both TEM and ERT are vital tools for hydrological parameter estimation. [ABSTRACT FROM AUTHOR]

Water quality assessment and its monitoring are necessary for areas of mining activities. In Malaysia, the mining industry is the backbone of the manufacturing and construction sectors. This study used spatio-temporal water quality modeling along a reach with mining activities during high and low discharges at Sungai (river) Lebir and Sungai Aring, situated in Gua Musang, Kelantan, Peninsular Malaysia. The objective was to assess the spatio-temporal environmental impact of mining activities during the wet and dry seasons. Data were collected at different locations along the reach. Point and non-point sources were near the mining site. Overland flow calculation at the mining site was found with the widely used SCS (Soil Conservation Service) curve number method. Several scenarios were analyzed, such as baseline, worst-case, and with-mitigation. The study revealed that baseline values of all parameters were either in a natural condition or slightly polluted, except for aluminum. All parameters were estimated at a high concentration from the mining site to downstream during the worst case of the wet season. Whereas, during the worst case of the dry season, no significant differences were observed compared to baseline values. In the with-mitigation scenario, parameter concentrations were improved and similar to baseline values. Overall, the scenario selection was helpful in the environmental impact assessment. Furthermore, this study will be significant in pre- and post-mining assessment and environmental clearance. [ABSTRACT FROM AUTHOR]

Topographic LIDAR can be used to estimate elevation values for dry areas down to the river water level during the extraction of river cross-sections (XS). However, LIDAR cannot accurately predict the submerged topography, which causes uncertainty in river XS area estimation. This uncertainty affects the channel water level and flood inundation depth estimation in in situ sparse data. Therefore, an alternative approach is presented to estimate unknown submerged topography (UST) using topographic LIDAR. The one dimension/two dimension Hydrologic Engineering Center River Analysis System (1D/2D HEC-RAS) model is used to simulate the estimated river XS with the help of in situ river water level and flow data which is later validated using in situ data. The results show that the proposed approach accurately estimates water level (error >0.5 m), channel flow areas, and floodplain water depths. Notably, the extent of the estimated floodplain overflow by UST models was in 94% agreement with the real XS. [ABSTRACT FROM AUTHOR]

A pneumonia outbreak was primarily reported in the fall of 2019 in Wuhan, Hubei province, China, with the identity SARS-CoV-2, a novel coronavirus. It quickly grew from a local epidemic to a global pandemic and was declared a public health emergency by the WHO. A total of three prominent waves were identified across the globe, with a slight temporal variability as per the geographical locations, and has impacted several sectors which connect the world. By March 2022, the coronavirus had infected 444.12 million people and claimed 6.01 million human lives worldwide, and these numbers have not yet stabilized. Our paper enlightens readers on the seven strains of human coronaviruses, with special emphasis on the three severe deadliest outbreaks (SARS-2002, MERS-2012, and COVID-19). This work attempts a comprehensive understanding of the coronavirus and its impact on the possible sectors that link the world through the economic chain, climate conditions, SDGs, recycling of the event, and mitigations. There are many points that are raised by the authors in the possible sectors, which are emerging or are as yet unnoticed and thus have not been taken into consideration. This comprehension will leave sets of new challenges and opportunities for the researchers in various streams, especially in earth sciences. Science-integrated research may help to prevent upcoming disasters as a by-product of (existing) epidemics in the form of coronavirus. [ABSTRACT FROM AUTHOR]

The groundwater from shallow alluvial aquifers of northern Kelantan, Malaysia, was analysed for stable isotopes (δ18O and δ2H) during northeast and southwest season to assess the dynamics of the recharge processes. The groundwater shows quite a large variation in isotopic signatures (18O ranges from -7.5 to 0.62 ‰ for northeast (NE) and from −7.4 to −4.98 ‰ during southwest (SW)). These values reflect the contribution of different recharge sources in the aquifer. During NE season, the average isotopic signature of groundwater (δ18O: −5.30‰) is similar to the rainfall (δ18O: −4.13‰) indicating that rainfall is the main source of recharge compared to the other sources. The SW season shows an isotopically distinct signature due to contribution from surface water bodies (river sources) and enriched irrigation return-flow. Interestingly, the groundwater average isotope signature in SW season (δ18O: −6.40‰) is very close to the surface water (δ18O: −6.47‰), indicating significant contributions from surface water bodies of the area. Overall, the isotope data suggests that shallow groundwater is very dynamic during SW season whereas in NE the impact of surface manifestations is less. The study highlights the significance of further studies to accurately quantify the recharge volumes from different sources that will help to model and manage the aquifers both qualitatively and quantitatively. Moreover, the quantification of irrigation return-flow is very essential component keeping in view the contaminant transport from the agricultural areas. [ABSTRACT FROM AUTHOR]

The present study is carried-out to have an idea about varying infiltration rates with varying soil types and cover in Kota Bharu- the capital of Kelantan state. The study area, covering a land area of about 394 km? lies between latitudes of 06°10'N and longitude of 102°20'E. Geologically, the area is mainly comprised of Quarternary alluvium having fluvial and marine origin which is constituted of mainly sand, gravel, silt and clay underlain by granite and metasedimentary rocks. The soil properties like texture, structure, water content, temperature and other factors like vegetation types and cover, and rainfall intensity play a significant role in controlling infiltration rate. Generally, coarse grained soils having large pore spaces with stable structure allows water from rainfall to enter unimpeded throughout a rainfall event. Otherwise, soils that have reduced infiltration may cause flooding in the area. From the soil classification map produced by Department of Agriculture (DOA), selected soils would be tested using double ring method to identify the infiltration rate in the study area. The method employed consists of two metal cylinders of diameter 30 cm and 60 cm that are driven partially into the soil. The ring is filled with specific level of water and the time at which water moves into the soil is measured, thus the rate of infiltration could be calculated in the field. An infiltration map will be produced at the end of the study which will be very useful for decision makers while dealing with flood management. The present study will be also very handy in agricultural field regarding the judicious and timely irrigation. [ABSTRACT FROM AUTHOR]

The groundwater (GW) and surface water (SW) interaction (SW-GW) through the hyporheic zone is a significant component in sustainable water resource management. The complexities in SW-GW interactions increase from a local to a regional scale and are affected by variation in hydraulic, hydrologic, and hydrogeologic (3H) processes. Controlling factors and their upscaling of these processes to assess SW-GW interaction have not been addressed sufficiently in previous studies. Additionally, it is unclear what the effective factors are at different scales during the upscaling. Therefore, the present review focused on controlling factors of 3H processes in SW-GW interaction and their upscaling techniques. Relevancy of controlling factors was identified at different scales. Applications of different approaches and their uncertainties were also discussed for the characterization of SW-GW interactions. The study revealed that the improved data from different approaches is crucial for machine learning training and its application in the SW and GW assessment at local, sub-catchment, and catchment scales. Based on the outcomes, a framework has been proposed to execute modalities of controlling factors using remote sensing, geophysics, and artificial intelligence. The proposed framework could help in handling big data and accurate upscaling for water resource management. [ABSTRACT FROM AUTHOR]