The response of aquatic macroinvertebrate communities to flow permanence within limestone springs and headwater streams was examined across the English Peak District. At the regional scale, macroinvertebrate communities of perennial and intermittent springs displayed significant differences in the number of taxa, macroinvertebrate community abundance, diversity indices (Shannon and Simpson indices) and the Berger-Parker dominance index at intermediate discharge. However, no significant difference was recorded between intermittent and perennial sites at high discharge or when all sampling occasions were pooled. At the catchment scale, the number of taxa, community abundance and Bray-Curtis similarity coefficients within the River Lathkill differed significantly between intermittent springs and other habitats. At both the regional and catchment scale the macroinvertebrate communities of intermittent springs were characterised by a small number of taxa displaying life cycle adaptations to intermittent aquatic habitats, particularly Trichoptera.

An assessment of the abandoned mine impacts on the concentrations and distribution of heavy metals in surface sediments and plant species within the vicinity of an ex-iron mine in Malaysia was conducted. The sequential extraction method was used to extract anthropogenic metals in sediments. The results showed that metals in EFLE, AR, and OO fractions were higher than ambient concentrations which indicate that heavy metals have been loaded from ex-iron mining area into the surrounding aquatic environments. The metal accumulation in the four dominant plant species grown naturally within the vicinity of Bukit Besi exiron mining was investigated. Exceptional elevated concentrations of metal were found in plants and surface sediments. Several established criteria were applied to determine the hyperaccumulator plants. The results revealed that Melastoma malabathricum and Pityrogramma calomelanos are classified as Fe and Al hyperaccumulators, while Scirpus triqueter, Melastoma malabathricum, and Pityrogramma calomelanos were undoubtedly hyperaccumulator for Cd.

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In order to evaluate the water quality of one of the most polluted urban river in Malaysia, the Penchala River, performance of eight biotic indices, Biomonitoring Working Party (BMWP), BMWP, BMWP, Average Score Per Taxon (ASPT), ASPT, BMWP, Family Biotic Index (FBI), and Singapore Biotic Index (SingScore), was compared. The water quality categorization based on these biotic indices was then compared with the categorization of Malaysian Water Quality Index (WQI) derived from measurements of six water physicochemical parameters (pH, BOD, COD, NH-N, DO, and TSS). The river was divided into four sections: upstream section (recreational area), middle stream 1 (residential area), middle stream 2 (commercial area), and downstream. Abundance and diversity of the macroinvertebrates were the highest in the upstream section (407 individual and H' = 1.56, respectively), followed by the middle stream 1 (356 individual and H' = 0.82). The least abundance was recorded in the downstream section (214 individual). Among all biotic indices, BMWP was the most reliable in evaluating the water quality of this urban river as their classifications were comparable to the WQI. BMWPs in this study have strong relationships with dissolved oxygen (DO) content. Our results demonstrated that the biotic indices were more sensitive towards organic pollution than the WQI. BMWP indices especially BMWP were the most reliable and could be adopted along with the WQI for assessment of water quality in urban rivers.

In recent years, many studies have stated the nutritional benefits of fish consumption: vitamins, proteins and omega-3 fatty acids, which may protect humans from adverse health effects, including heart disease and stroke. This study aimed to evaluate the concentration of Cu, Pb and As in the liver, gills and muscles of tilapia fish (Oreochromis niloticus) and to calculate the weekly intake from eating tilapia collected from Cempaka Lake, Selangor -Peninsular Malaysia during the period between April 2009 to February 2010. The elemental concentrations were determined using inductively -coupled plasma mass spectrometry (ICP-MS). The results showed that all heavy metal concentrations were significantly different among fish organs, and between calendar months. The data showed that Cu levels in liver, gills and muscles were 491.30, 3.70 and 1.82 µg/g dry weight (dw), respectively. Meanwhile Pb levels were 2.71, 1.04 and 0.48 µg/g dw, respectively and As levels were 6.26, 4.18 and 1.79 µg/g dw, respectively. Significant changes occurred in Cu, Pb and As levels in tilapia fish organs in Cempaka Lake over the period of 11 months. Tilapia weekly intake was calculated based on mean Cu, Pb and As concentrations in the muscle of tilapia fish and adult consumption of tilapia in Malaysia which averages at 160 grams per day. Furthermore, tilapia weekly and daily human intakes for Cu, Pb and As were compared with the Provisional Tolerable Weekly Intake (PTWI) established by the JECFA (WHO/FAO) presenting values below the PTWI. Metal levels in fish muscle were found to be lower than the maximum permitted concentrations recommended by various authorities; hence, consumption of tilapia fish from Cempaka Lake is currently safe for humans.