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641.
Huang XL  Zhang JZ 《Chemosphere》2011,85(8):1227-1232
Organophosphonate, characterized by the presence of a stable, covalent, carbon to phosphorus (C-P) bond, is a group of synthetic or biogenic organophosphorus compounds. The fate of these organic phosphorus compounds in the environment is not well studied. This study presents the first investigation on the sorption of phosphorus (P) in the presence of two model phosphonate compounds, 2-aminothylphosphonoic acid (2-AEP) and phosphonoformic acid (PFA), on marine carbonate sediments. In contrast to other organic P compounds, no significant inorganic phosphate exchange was observed in seawater. P was found to adsorb on the sediment only in the presence of PFA, not 2-AEP. This indicated that sorption of P from phosphonate on marine sediment was compound specific. Compared with inorganic phosphate sorption on the same sediments, P sorption from organic phosphorus is much less in the marine environment. Further study is needed to understand the potential role of the organophosphonate compounds in biogeochemical cycle of phosphorus in the environment.  相似文献   
642.
Following decades of international collaboration to restore the Baltic Sea, we provide an assessment of the domestic implementation of measures agreed to limit diffuse agricultural pollution and the patterns of policy instruments applied. Despite the Helsinki Convention being unusually specific in detailing what measures countries should introduce, we find many shortcomings. These are most pronounced in the larger countries (Poland, Germany and Russia), while smaller countries perform better, notably Sweden and Estonia. The patterns of policy instruments applied differ, influenced by domestic politics. The limited use of complementary policy instruments suggests that other priorities overrule full and effective implementation, with engagement mirroring the advantages that a restored Baltic Sea can bring to countries. Using the European Agricultural Fund for Rural Development to support farmers in managing nutrients, particularly advisory services and investments in modern manure management technologies, represents a significant opportunity for reducing agricultural pollution in most countries.Supplementary InformationThe online version contains supplementary material available at 10.1007/s13280-021-01549-3.  相似文献   
643.
Shipping is an important source of pollution affecting both atmospheric and aquatic environments. To allow for efficient mitigation of environmental degradation, it is essential to know the extent of the impacts of shipping in relation to other sources of pollution. Here, we give a perspective on a holistic approach to studies of the environmental impacts of operational shipping through presentation of an assessment framework developed and applied on a case of shipping in the Baltic Sea. Through transfer of knowledge and concepts, previously used in assessments of air pollution, now applied to assessments of marine pollution and underwater noise, the horizon of understanding of shipping-related impacts is significantly improved. It identifies the main areas of environmental degradation caused by shipping and potential improvements through legislation and technological development. However, as the vast majority of contaminants discharged into the sea are not routinely monitored and assessed, the links between pressure of contaminants from shipping and environmental state and impacts will not be caught in the current environmental regulatory frameworks.  相似文献   
644.
Background, aim, and scope  At tropical latitudes, and especially on the semi-arid coasts of the Brazilian Northeast, the rainfall regime governs the water quality of estuaries due to the pronounced difference between the rainy and dry seasons. These changes may be responsible for seasonal changes in bioavailability of mercury (Hg) and other pollutants to the estuarine and coastal biota. Mercury bioaccumulates along estuarine–marine food chains usually result in higher concentrations in tissues of top predators and posing a risk to both marine mammals and humans alike. The Goiana River Estuary (7.5° S) is a typical estuary of the semi-arid tropical regions and supports traditional communities with fisheries (mollusks, fish, and crustacean). It is also responsible for an important part of the biological production of the adjacent coastal waters. Materials and methods   Trichiurus lepturus (Actinopterygii: Perciformes) is a pscivorous marine straggler. Fish from this species (n = 104) were captured in a trapping barrier used by the local traditional population and using an otter trawl net along the main channel of the low estuary during two dry seasons (D1 = November, December 2005, January 2006; D2 = November, December 2006, January 2007) and the end of a rainy season (R = August, September, October 2006). Fish muscle samples were preserved cold and then freeze-dried prior to analysis of its total mercury (Hg-T) contents. Total mercury was determined by cold vapor atomic absorption spectrometry (CV-AAS) with sodium borohydride as a reducing agent. Results  The studied individuals (n = 104) were sub-adult (30–70 cm, 71 ind.) and adult fish (>70 cm, 33 ind.). Weight (W) (204.1 ± 97.9 g, total biomass = 21,229.7 g) and total length (TL) (63.1 ± 10.1 cm, range 29.5–89.0 cm) presented a significant (p < 0.05) correlation. Two-way ANOVA (n = 81) showed that TL and W had significant differences (p < 0.05) among seasons, being higher in D1 than in D2 and R, respectively. Moreover, season vs. month interaction were detected for the variables length and weight. For the variable weight was detected significant difference for the factor month (p < 0.05). It suggests that the fish enter the estuary at the end of the rainy season and increase in length and weight during the time they spend in the estuary. Fish from this estuary are shown to be fit for human consumption (125.3 ± 61.9 μgHg-T kg–1 w.wt.; n = 104). Fish mercury contents increased with size and weight. Correlations between TL and Hg-T (r = 0.37286) and between W and Hg-T (r = 0.38212) were significant (p < 0.05). Dryer months showed higher mercury concentrations in fish (D1 773.4 ± 207.5 μgHg-T kg–1 d.wt., n = 27; D2 370.1 ± 78.8 μgHg-T kg–1 d.wt., n = 27; R 331.2 ± 138.5 μgHg-T kg–1 d.wt., n = 27). The variable mercury concentration showed differences in relation to the factor season (p < 0.05), where fish captured during the first dry season showed the highest concentration of mercury. The correlation between Hg-T and rainfall (Rf) showed a negative correlation (r = –0.56; p < 0.05). Discussion  The main likely source of mercury to this estuary is diffuse continental run off, including urban and industrial effluents. Since concentration of mercury in fish tissue is negatively correlated to rainfall, but positively correlated with fish length and weight, it suggests that fish growth in this estuary results in mercury uptake and concentration on the fish tissue. In the dry season of 2005–2006, when rainfall remained below the historic average, fish bioaccumulated significantly more mercury than in the dry season 2006–2007, when rainfall was within the predictable historic average. It is suggested that less rainfall, and consequently less particulate matter and less primary production in the estuary, make mercury more available to the higher levels of the estuarine food chain. In the case of higher rainfall, when river flow increases and water quality in the estuary is reduced, mercury probably is quickly exported associated to the particulate matter to the adjacent coastal waters where it then disperses. This species is a potential routine bioindicator for mercury contamination of the biota, but so far was used only with a limited number of individuals and contexts. Conclusions  Fish from the Goiana River estuary can still be safely consumed by the local population. However, any further contamination of this resource might lead to total mercury levels above the recommended limits for pregnant women and small children. The proposed heavy dependency of total mercury levels in fish on water quality indicates that land use and water quality standards must be more closely watched in order to guarantee that best possible practices are in place to prevent bioaccumulation of mercury and its transfer along the food chain. Human interventions and climatic events which affect river water flow are also playing a role in the mercury cycle at tropical semi-arid estuaries. Recommendations and perspectives   T. lepturus is largely consumed by coastal populations of tropical and sub-tropical countries all over the world. It is also consumed by a number of marine mammals over which we have a strong conservation interest. This species is also a link among different ecosystems along the estuarine ecocline. Therefore, knowledge of its degree of contamination might contribute to public health issues as well as marine conservation actions. Studies on mercury and other contaminants using this species as bioindicator (cosmopolitan, readily available) could help elucidating mechanisms through which pollutants are being transferred not only through the food chain, but also from estuarine–coastal–open waters. In addition, using the same species in marine pollution studies, especially as part of a mosaic of species, allows for wide range comparisons of marine food chain contamination.  相似文献   
645.
Composition and abundance of submerged marine litter at six selected sites within a coral reef area along the Jordanian coast of the Gulf of Aqaba have been estimated. The litter was collected in clean up voluntary campaigns that took place in the period between 25 August 2003 and 29 February 2004. A total of 10,506 items weighing 1159 kg were collected during the survey. Mean litter density in the individual sampling sites varied between 1 and 6 items/m(2) with an overall mean density of 2.8 items/m(2). The mean weight of the collected items per sampling site varied between 0.06 and 1.06 kg/m(2) with an overall mean of 0.31 kg/m(2). Plastic accounted for 42% of the collected items, fishing gear was the second most abundant (31%) while metal was the third most abundant item (17%). By comparison, cardboard constituted 1%, and rubber and other items accounted for less than 1% of the total items collected during the campaigns. Approximately 61% of the plastics consisted of bags followed by bottles (24%), plastic containers and sheets accounted for 13 and 2%, respectively. Statistical analysis indicates no significant differences between the sites in terms of litter count and weight. Potential sources are pointed out and recommendations and actions to address the problem are suggested.  相似文献   
646.
This article presents results pertaining to a risk assessment of the potential consequences of a hypothetical accident occurring during the transportation by ship of spent nuclear fuel (SNF) along an Arctic coastline. The findings are based on modelling of potential releases of radionuclides, radionuclide transport and uptake in the marine environment. Modelling work has been done using a revised box model developed at the Norwegian Radiation Protection Authority. Evaluation of the radioecological consequences of a potential accident in the southern part of the Norwegian Current has been made on the basis of calculated collective dose to man, individual doses for the critical group, concentrations of radionuclides in seafood and doses to marine organisms. The results of the calculations indicate a large variability in the investigated parameters above mentioned. On the basis of the calculated parameters the maximum total activity (“accepted accident activity”) in the ship, when the parameters that describe the consequences after the examined potential accident are still in agreement with the recommendations and criterions for protection of the human population and the environment, has been evaluated.  相似文献   
647.
This article develops a dynamic model of efficient use of exhaustible marine sand resources in the context of marine mining externalities. The classical Hotelling extraction model is applied to sand mining in Ongjin, Korea and extended to include the estimated marginal external costs that mining imposes on marine fisheries. The socially efficient sand extraction plan is compared with the extraction paths suggested by scientific research. If marginal environmental costs are correctly estimated, the developed efficient extraction plan considering the resource rent may increase the social welfare and reduce the conflicts among the marine sand resource users. The empirical results are interpreted with an emphasis on guidelines for coastal resource management policy.  相似文献   
648.
Biodiversity of marine ecosystems is integral to their stability and function and is threatened by anthropogenic processes. We conducted a literature review and meta-analysis of 216 studies to understand the effects of common contaminants upon diversity in various marine communities. The most common diversity measures were species richness, the Shannon-Wiener index (H′) and Pielou evenness (J). Largest effect sizes were observed for species richness, which tended to be the most sensitive index. Pollution was associated with marine communities containing fewer species or taxa than their pristine counterparts. Marine habitats did not vary in their susceptibility to contamination, rather a ∼40% reduction in richness occurred across all habitats. No class of contaminant was associated with significantly greater impacts on diversity than any other. Survey studies identified larger effects than laboratory or field experiments. Anthropogenic contamination is strongly associated with reductions in the species richness and evenness of marine habitats.  相似文献   
649.
The objective of this study is to present an efficiency-perception impact assessment based upon the integration of fuzzy logic (FL) of the "Productive Reconversion" conservation program (PRP) instituted by the Mexican government, in the upper Gulf of California and the Colorado Delta Biosphere Reserve. This approach enables environmental analysts to deal with the intrinsic imprecision and ambiguity associated with people's judgments and conclusions. The application of FL to the assessment of program efficiency is illustrated in this work, demonstrating how subjective perceptions can be converted into quantitative values easy to evaluate during the decision-making process.  相似文献   
650.
Yi AX  Leung KM  Lam MH  Lee JS  Giesy JP 《Chemosphere》2012,89(9):1015-1025
The state of scientific knowledge regarding analytical methods, environmental fate, ecotoxicity and ecological risk of triphenyltin (TPT) compounds in marine ecosystems as well as their exposure and health hazard to humans was reviewed. Since the 1960s, TPT compounds have been commonly applied as biocides for diverse industrial and agricultural purposes. For instance, they are used as active ingredients in antifouling systems on marine vessels and mariculture facilities, and as fungicides in agriculture. Due to their intensive use, contamination of coastal waters by TPT and its products of transformation has become a worldwide problem. The proportion of quantified TPT to total phenyltin compounds in the marine environment provides evidence that TPT is photodegradable in water and sediment but resistant to biotransformation. Concentrations of TPT in marine biota are consistently greater than concentrations in water and sediment, which implies potential of TPT to bioaccumulate. TPT is toxic to both marine plants and animals. The predicted no effect concentration (PNEC) for TPT, as determined by use of the species sensitivity distribution approach, is 0.64 ng L−1. In some parts of the world, concentrations of TPT in seawater exceed the PNEC, indicating that TPT can pose risks to marine life. Although there is negligible risk of TPT to average human consumers, TPT has been detected in blood of Finnish people and the concentration was greater in fishermen who ate more seafood. It is, therefore, advocated to initiate regular monitoring of TPT in blood and breast milk of populations that consume greater amounts of seafood.  相似文献   
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