No abstract available

[en] Environmental tritium (³H) is a powerful tracer of groundwater age, and is a key tracer of groundwater movement. ³H concentrations in precipitation have exponentially declined over the past decades as the anthropogenic bomb ³H peak has all but disappeared. Today, the environmental ³H concentrations are close to natural levels of cosmic production. The current ultra-low levels therefore pose a problem for the measurement of low level ³H concentrations in natural water samples using ³H enrichment units of the past, which mostly were built for enrichment of 250 - 500 mL water samples. Therefore, a new tritium enrichment unit called as New Tritium Enrichment System (NTES) had been developed that can enrich up to 2 L of water to concentrate current levels of ³H, leading to more precise ³H analysis for hydrological applications. This paper will explained the step how to measured environmental ³H using enrichment procedure. This technique involved five steps which is primary distillation, electrolysis, neutralization, final distillation and counting. (author)

[en] A study of seawater intrusion has been proposed in the coastal area of Pahang. Electrical resistivity tomography (ERT) is a geophysical technique that used in this study. The survey was conducted at UMP, Tanjung Batu and Nenasi using Wenner-Schlumberger protocol. Electrical resistivity profile obtained from the survey indicates an area with low resistivity value (<5Ωm) associated with the resistivity value of seawater. (author)

[en] Anthropogenic activities such as changes of land use for coastal development are the major factors affecting the sustainability of mangrove area. Mangrove forests in Kuala Selangor Nature Park (KSNP) is one of the areas that should be monitored for any potential source of pollution, and this can be performed by using stable isotopes as the important indicators. Vegetation samples from several palm and mangrove species were analysed for δ¹³C, δ¹⁵N and δ³⁴S stable isotopes. The samples were collected from nine different locations comprising of KSNP area, water canal, residential area, sluice gate, aquaculture area, landslide area, agriculture area, jetty and river confluence area. The δ¹³C, δ¹⁵N and δ³⁴S value in the samples are found to be ranged from -33.05‰ to -13.33‰, +1.69‰ to +9.27‰, and +7.83‰ to +8.50‰, respectively. IsoSource modelling software was used and found that 50% is the highest source proportion identified in aquaculture location demonstrating that the area is the main pollution source in this study. The findings from this study could be used for further control measures by local authority in order to preserve the flora and fauna in KSNP. (author)