Water Quality Changes in Chini Lake, Pahang, West Malaysia

A study of the water quality changes of Chini Lake was conducted for 12 months, which began in May 2004 and ended in April 2005. Fifteen sampling stations were selected representing the open water body in the lake. A total of 14 water quality parameters were measured and Malaysian Department of Environment Water Quality Index (DOE-WQI) was calculated and classified according to the Interim National Water Quality Standard, Malaysia (INWQS). The physical and chemical variables were temperature, dissolved oxygen (DO), conductivity, pH, total dissolved solid (TDS), turbidity, chlorophyll-a, biochemical oxygen demand (BOD), chemical oxygen demand (COD), total suspended solid (TSS), ammonia-N, nitrate, phosphate and sulphate. Results show that base on Malaysian WQI, the water in Chini Lake is classified as class II, which is suitable for recreational activities and allows body contact. With respect to the Interim National Water Quality Standard (INWQS), temperature was within the normal range, conductivity, TSS, nitrate, sulphate and TDS are categorized under class I. Parameters for DO, pH, turbidity, BOD, COD and ammonia-N are categorized under class II. Comparison with eutrophic status indicates that chlorophyll-a concentration in the lake was in mesotrophic condition. In general water quality in Chini Lake varied temporally and spatially, and the most affected water quality parameters were TSS, turbidity, chlorophyll-a, sulphate, DO, ammonia-N, pH and conductivity.     

Coastal Flood Risk Analysis Using Landsat-7 ETM+ Imagery and SRTM DEM: A Case Study of Izmir, Turkey

The Intergovernmental Panel on Climate Change (IPCC) reports an acceleration of the global mean sea-level rise (MSLR) in the twentieth century in response to global climate change. If this acceleration remains constant, then some coastal areas are most likely to be inundated by the year 2100. The ability to identify the differential vulnerability of coastlines to future inundation hazards as result of global climate change is necessary for timely actions to be taken. Yildiz et al. (Journal of Mapping, 17, 1-75, 2003) reported that the local MSLR in the city of Izmir rose at a rate of 6.8 +/- 0.9 mm year(-1) between 1984 and 2002. In this study, the spatial distribution of the coastal inundation hazards of Izmir region was determined using not only land-use and land-cover (LULC) types derived from the maximum likelihood classification of Landsat-7 Enhanced Thematic Mapper Plus (ETM+) multi-spectral image set but also the classification of the digital elevation model (DEM) acquired by the shuttle radar topography mission (SRTM). Coastal areas with elevations of 2 and 5 m above mean sea-level vulnerable to inundation were found to cover 2.1 and 3.7% of the study region (6,107 km(2)), respectively. Our findings revealed that Menemen plain along Gediz river, and the settlements of Karsiyaka, Alacati, Aliaga, Candarli and Selcuk are at high risk in order of decreasing vulnerability to permanent and episodic inundation by 2100 under the high MSLR scenarios of 20 to 50 mm year(-1).     

Comparative evaluation of a bioluminescent bacterial assay in terrestrial ecotoxicity testing

Despite the widespread and successful use of luminescence-based bioassays in water testing, their applications to soils and sediments is less proven. In part this is because such bioassays have mainly been carried out in an aqueous-based medium and, as such, favour contaminants that are readily water-soluble. In this study, aqueous solutions and soils contaminated with heavy metals (HM), polar organic contaminants and hydrophobic organic contaminants (HOCs) were tested using a range of luminescence-based bioassays (Vibrio fischeri, Escherichia coli HB101 pUCD607 and Pseudomonas fluorescens 10586r pUCD607). For the first two chemical groups, the assays were highly reproducible when optimised extraction procedures were employed but for HOCs the bioassay response was poor. Quantitative structure-activity relationships (QSARs) obtained from aqueous solutions had a linear response although correlation for the chemicals tested using bacterial bioassays was significantly less sensitive than that of sublethal tests for Tetrahymena pyriformis. Bacterial and Dendrobaena veneta bioassay responses to extracts from HM amended soils showed that a clear relationship between trophic levels could be obtained. There is no doubt that the wide range of bioluminescent-based bioassays offers complementary applications to traditional testing techniques but there is a significant need to justify and optimise the extraction protocol prior to application.     

Composition of a Spanish sewage sludge and effects on treated soil and olive trees

The effects of sewage sludge (SL) application on the soil and olive trees (Olea europaea L., cultivar: cornicabra) were studied. The plants were grown in 8.5L pots and subjected to the following treatments: 0, 3.66, 7.32, 14.65, 29.3, 58.6, and 117.2 g SL kg(-1) soil that corresponded, respectively, to 0, 4, 8, 16, 32, 64 and 128 M g ha(-1) dry weight of sewage sludge. The application of SL at the rates 64 and 128 M g ha(-1) produced leaf tip burning and leaf drop after 120 days, although cumulative metal pollutant loading rates was below USEPA and European regulations. This toxicity symptom could be caused by the high sodium levels in the leaves (over 0.19%), which can damage olive tree development. The Na contents of leaves were well correlated with soil Na content (r2: 0.91). In general, SL rates significantly increased the level of Cr, Ni, Cu, Zn, Cd and Pb in soil and plants, but these concentrations were in the normal ranges, except for the Zn concentration, which was over the critical soil content for the rates of 32, 64, 128 Mg ha(-1) but not in the leaves. Results suggested that regulations about the utilization of sewage sludge on agricultural land should consider the limit values for salt, and not only metals, that may be added to soil, in order to minimize the risk of negative effects to plant health.     

Road soil retention of Pb leached from MSWI bottom ash

Municipal solid waste incinerator (MSWI) bottom ash may be used as a road construction material; it potentially contains however a sizable quantity of heavy metals, which under the effect of rainfall infiltration through the road structure can be leached out from the material and infiltrate into the underlying soil. An eco-compatibility assessment of MSWI bottom ash reuse in road construction applications necessitates examining the solubility and retention of heavy metals in road soils. This study is dedicated to Pb transfer, sorption and desorption (NEN 7341 standard test) within various soils. These experiments yield results relative to the interaction between road soils and an MSWI bottom ash leachate representative of a "fresh" product, with a high leaching potential. For the soils investigated, the sorption of lead varies between 90% and 99%. For an extraction at pH 7, Pb release is very low (<2%) for all soils, while at pH 4 leaching varies between 4% and 47%. This work shows that Pb may be fixed by some types of road soil in mostly stable forms.     

Chemical-mineralogical characterisation of coarse recycled concrete aggregate

The construction industry is now putting greater emphasis than ever before on increasing recycling and promoting more sustainable waste management practices. In keeping with this approach, many sectors of the industry have actively sought to encourage the use of recycled concrete aggregate (RCA) as an alternative to primary aggregates in concrete production. The results of a laboratory experimental programme aimed at establishing chemical and mineralogical characteristics of coarse RCA and its likely influence on concrete performance are reported in this paper. Commercially produced coarse RCA and natural aggregates (16-4 mm size fraction) were tested. Results of X-ray fluorescence (XRF) analyses showed that original source of RCA had a negligible effect on the major elements and a comparable chemical composition between recycled and natural aggregates. X-ray diffraction (XRD) analyses results indicated the presence of calcite, portlandite and minor peaks of muscovite/illite in recycled aggregates, although they were directly proportioned to their original composition. The influence of 30%, 50%, and 100% coarse RCA on the chemical composition of equal design strength concrete has been established, and its suitability for use in a concrete application has been assessed. In this work, coarse RCA was used as a direct replacement for natural gravel in concrete production. Test results indicated that up to 30% coarse RCA had no effect on the main three oxides (SiO2, Al2O3 and CaO) of concrete, but thereafter there was a marginal decrease in SiO2 and increase in Al2O3 and CaO contents with increase in RCA content in the mix, reflecting the original constituent's composition.     

Pilot installation for the thermo-chemical characterisation of solid wastes

The increasing production and the large variety of wastes require operators of thermal treatment units to continuously adapt the installations or the functioning parameters to the different physical and chemical properties of the wastes. Usually, the treated waste is encountered in the form of heterogeneous mixtures. The classical tests such as thermogravimetry and calorimetric bomb operate component by component, separately. In addition to this, they can analyse only small quantities of waste at a time (a few grams). These common tests are necessary but insufficient in the global waste analysis in the view further thermal treatment. This paper presents an experimental installation, which was designed and built at the CNRS Science Division, Department of Industrial Methods, Compiègne University of Technology, France. It allows the determination of waste thermal and chemical properties by means of thermal treatment. Also, it is capable of continuously analysing significant quantities of waste (up to 50kg/h) as compared to the classical tests and it can work under various conditions: The installation reproduces the process conditions from incinerators or pyrolysis reactors. It also provides complete information on the kinetics of the waste thermal degradation and on the pollutant emissions. Using different mixtures of components present in the municipal solid waste and also in the reconstituted MSW samples, we defined a series of criteria for characterising waste behaviour during the stages of the main treatment process such as: feeding, devolatilisation/oxidation, advancement, solid residue evacuation, and pollutants emission.     

Municipal waste compost as an alternative to cattle manure for supplying potassium to lowland rice

The importance of the use of potassium in agriculture is increasing in South Asia for making most productive use of the nutrient in terms of economic returns. Nutrient supply traditionally by cattle manure is constrained by its insufficient availability. Municipal waste compost may be an alternative source of nutrient supplements. Field experiments were conducted at the Experimental Farm of Calcutta University, West Bengal, India during the wet seasons of 1997, 1998 and 1999 on flooded lowland rice. Potassium fractions in municipal waste compost and cattle manure were determined by sequential extraction and also the potassium uptake by rice to compare the effectiveness of municipal waste compost with traditional manure. Potassium was significantly bound to the organic matter in municipal waste compost. Potassium uptake by rice grain and straw increased significantly with the combined application of organics and fertilizers and it was higher in grain than in straw. Water-soluble and non-exchangeable potassium contents of municipal waste compost and cattle manure were highly correlated with the uptake of potassium by straw and grain. Exchangeable and residual potassium were also significantly correlated with the uptake of potassium by straw and grain of rice. Much higher uptake of K in rice straw and rain resulted from applying the manures in conjunction with fertilizers than when applied singly.     

Competition between phenanthrene, chrysene, and 2,5-dichlorobiphenyl for high-energy adsorption sites in a sediment

We determined the maximum amounts of added phenanthrene, chrysene, and 2,5-dichlorobiphenyl sorbed onto high-energy adsorption sites in a sediment on bi-solute experiments. The bi-solute pairs were phenanthrene/chrysene and phenanthrene/2,5-dichlorobiphenyl. On the bi-solute sorption experiments, one solute was introduced and equilibrated with sediment prior to addition of the second solute. The values for the maximum amounts adsorbed onto high-energy sites revealed that, after equilibration of the first solute, still some high-energy sites could be occupied by the second solute. Phenanthrene, chrysene, and 2,5-dichlorobiphenyl seem to share about 30% of the accessible high-energy adsorption sites in the sediment employed.     

Bioaccumulation of anthropogenic contaminants by detritivorous fish in the Río de la Plata estuary: 2-Polychlorinated biphenyls

The temporal variability and bioaccumulation dynamics of individual PCBs were studied in a detritivorous fish (Sábalo: Prochilodus lineatus) collected from 1999 to 2005 in the polluted Buenos Aires coastal area. Fish muscles contain high concentrations of total PCBs (11+/-7.2, 4.6+/-3.4 or 19+/-13 microg g(-1), dry, fresh and lipid weight, respectively) reflecting chronic bioaccumulation from sewage-industrial particulates. On a temporal basis, lipid normalized PCBs concentrations peaked by the end of 2001-2002 coincident with the rainiest period over the last four decades and shortly after PCB prohibition in the country, reflecting massive discharges to the coastal ecosystem. PCB composition in fish muscles show a prevailing contribution of hexachlorobiphenyls (35+/-4.2%), followed by hepta (23+/-3.0%), penta (20+/-3.6%), tri-tetra (16+/-4.8%) and minor proportions of octa-decachlorobiphenyls (5.7+/-3.1%) similar to an Aroclor 1242-1254-1260 1:2:4 mixture. During 2001-2002 maxima fish showed an enrichment in tri-tetrachlorobiphenyls ( approximately 1242-1254-1260 1:1:1 mixture) denoting a fresher signature. Fish/settling material lipid-organic carbon accumulation factors (BSAFs: 2.4-46, average: 21+/-10) plotted against kow showed a parabolic trend (BSAFs=-0.38 log kow2 + 5.16 log kow -15.85; R2=0.46) maximizing at hexa, hepta and octachlorobiphenyl 203 with reduced bioaccumulation of a few hepta (170, 191) and most octa-decachlorobihenyls suggesting limited intestinal absorption.