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ABSTRACTThe sinking of the MV Rena on Astrolabe Reef (Otaiti) in the Bay of Plenty, New Zealand, resulted in the release of oil and ship debris, including dangerous goods carried as cargo. Two key questions of concern to the public and environmental managers were posed immediately: what was the impact of the Rena oil spill and how long would it take for the marine environment to recover? The research that began immediately after the ship grounded provided answers, as documented in this special issue. 相似文献
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DR. M. ERDÉLYI 《水文科学杂志》2013,58(1):44-52
SUMMARY Many hydrological systems exhibit long periods of quiescent behaviour, broken only occasionally by short periods of comparatively intense activity. Clear examples arise in stream run-off measurements and in ground water table observations. The number of measurements recorded can then be considerably reduced by reducing the frequency of recording over the quiescent periods. The paper describes an algorithm whereby this reduction is attained in an optimum manner. When recordings can be accepted directly by a computer, the algorithm simply provides a translation programme Whereby the quality of data may be very considerably reduced. Other applications are, however, discussed. The problems of Optimum representations is first presented, and choices of norm indicated. Using a particular norm, it is shown that the optimum representation is characterised, under certain limiting conditions, by the property that the second moments of the second derivatives are constant over all optimum intervals. This characterisation is used to construct an iterative difference scheme, whereby a certain truncation error is accepted. Sufficient conditions for stability of the scheme are determined and these incorporated into a computer programme. The programme has been tested on a variety of data with satisfactory results. In conclusion, a further development of the method is indicated. 相似文献
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The San Francisco Estuary Regional Monitoring Program initiated surveillance monitoring to identify previously unmonitored synthetic organic contaminants in the San Francisco Estuary. Organic extracts of water samples were analyzed using gas chromatography-mass spectrometry in full scan mode. The major contaminant classes identified in the samples were fire retardants, pesticides, personal care product ingredients, and plasticizers. Evidence from the literature suggests that some of these contaminants can persist in the environment, induce toxicity, and accumulate in marine biota and in higher food chain consumers. The major sources of these contaminants into the marine environment are the discharge of municipal and industrial wastewater effluents, urban stormwater, and agricultural runoff. As a proactive effort, it is suggested that surveillance studies be used routinely in monitoring programs to identify and prevent potential problem contaminants from harming the marine environment. 相似文献
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Jelena S. Kiurski Ivana B. Oros Nebojsa M. Ralevic Jasmina Stefanov 《Stochastic Environmental Research and Risk Assessment (SERRA)》2015,29(6):1709-1720
This study presents the application of different chemometric approaches on the dataset obtained during the monitoring of offset printing wastewater quality in Pozarevac, Serbia. Collecting of wastewaters was performed during a working week, five working days, in five offset printing facilities. Twenty five physico-chemical parameters were analyzed in wastewaters using the standard analytical and instrumental methods. The obtained dataset were subjected to cluster analysis and principal component analysis. Cluster analysis showed four groups of similarity between the printing facilities reflecting the different physico-chemical characteristics and pollution levels of studied wastewaters. Principal component analysis identified two principal components responsible for the data structure explaining 86 % of total variance of offset printing wastewaters. The obtained principal components indicate the parameters that are the most responsible for variation of offset printing wastewaters. This study clearly demonstrates the usefulness of chemometric methods in analysis of printing wastewater quality, identification of the main sources and understanding of spatial variations in wastewater quality. Also, it could be useful for the selection of an appropriate wastewater treatment plant. 相似文献
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Bivalve tissue samples were examined over a range of spatial and temporal scales (1993-2001) to determine PAH distributions, trends, and possible sources. Mussels (Mytilus californianus), oysters (Crassostrea gigas), and clams (Corbicula fluminea) were deployed for three months in the estuary at stations remote from known point source discharges. The range of summation operatorPAH detected in bivalves was oysters 184-6899 microg/kg dry wt (mean 678 microg/kg dry wt), mussels 21-1093 microg/kg dry wt (mean 175 microg/kg dry wt), and clams 78-720 microg/kg dry wt (mean 323 microg/kg dry wt). Linear regression analysis showed no statistically significant (p>0.05) temporal trends in clam and mussel summation operatorPAH at any of the deployment stations or estuary segments. On the other hand, a statistically significant (p<0.05) decreasing trend was found in summation operatorPAH in oysters at the Petaluma River station, and in the North Estuary segment. PAH isomer pair ratios applied as diagnostic indicators suggested that the bioaccumulated PAH were derived primarily from petroleum combustion, with lesser amounts derived from biomass and coal combustion, and unburned petroleum. 相似文献
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