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991.
The Piratininga Lagoon is a coastal, choked, and brackish ecosystem in SE Brazil, where uncontrolled discharge of domestic sewage led to eutrophication, increasing massive proliferation of benthic macroalgae, and decrease of the lagoon mean depth. In 1992, a dam was constructed by the local Municipality at its tidal channel aiming at stabilising its water level. Main physico-chemical parameters, together with macroalgae biomass, nutrient concentrations in the water column, particulate organic carbon, and chlorophyll a were recorded monthly at 4 sampling stations within the Piratininga lagoon from April 1994 to April 1995. The data, compared with “before-lock” existing studies, show that nutrients and chlorophyll a concentrations significantly increased after the lock construction. Based on the functioning of the ecosystem, we propose to harvest the algal mats before their decomposition period in order to partly remove the nutrient stocks from the lagoon and the future ecosystem modelling to predict the impact of natural and anthropogenic eutrophication.  相似文献   
992.
The concentration of a large spectrum of environmental contaminants (PCBs, PAHs, pesticides and metals) was assessed in surface sediments of two Ligurian harbours (Sanremo and Alassio, NW Mediterranean Sea, Italy) and their relative impact on micro–meiobenthic assemblages was analysed. Concentration, distribution and relative importance of the different contaminants varied considerably between harbours in relation to the different anthropic activities and contamination sources. Results from Principal Component Analysis indicated that high levels of contaminants were typically correlated with low micro–meiobenthic abundance in the sediment. Heavy metals and the organic enrichment were the main factors affecting the distribution and abundance of the bacterial and meiofaunal assemblages in Alassio harbour, whereas hydrocarbons and pesticides played a major role in Sanremo sediments. Neither the bacteria density nor the meiofauna abundance were dependent on sediment grain size, suggesting that micro–meiobenthic parameters may be under the influence of other variables. Our results suggest that high concentrations of contaminants independently from their source or typology are responsible for the impact observed on micro–meiobenthic assemblages in these harbours.  相似文献   
993.
Federal and State agencies have recently advocated risk-based analysis as a mechanism for advancing regulatory reform and safety determination in marine systems. the present investigation promotes this objective through the development of risk-based environmental planning strategies for oil spill contingency plans. This alternative approach to contingency planning departs from conventional methodology by employing quantitative risk assessment methods to identify hazardous oil spill zones and sensitive environmental areas, Ro and Re respectively. the product of this conversion is referenced on a single “Risk” layer within a Geographic Information System (GIS) framework allowing coastal managers to evaluate natural resource data with associated elements of oil spill risk. As a new tool for coastal pollution management, risk-based environmental planning strategies have shown potential for evolving more efficient oil spill contingency plans.  相似文献   
994.
The European WFD (2000/60/EC) requires the assessment of the ecological quality status of water bodies, and gives great importance to the biological components of the ecosystem. A multimetric, fuzzy-based index for the evaluation of environmental quality (FINE: Fuzzy INdex of Ecosystem integrity) has been developed. The FINE index was calculated at 7 sites in the Sacca di Goro and the Valli di Comacchio (Adriatic Sea), where water and sedimentary chemical data were available for the years 2004 and 2005. A significant positive correlation was found between FINE values and dissolved oxygen, while significant negative correlations were observed between FINE values and transparency, nitrogen and phosphorous in the water column, and heavy metals and PCB in the sediments.  相似文献   
995.
The biomarker approach has been used for 25 years to study the environmental quality of marine, brackish and freshwater ecosystems. Biomarkers may indicate health status and can be applied to organisms of all zoological phyla by destructive or non destructive methods. For 5 years we have been using this approach in zooplankton to detect ecotoxicological alterations at low levels of the food chain due to contaminants. Here we review our approach to validate and apply biomarker techniques in zooplankton. We discuss advantages, limitations, some results and future research. We indicate that biomarkers in zooplankton can be used as new indices of trophic status and ecological integrity of Italian marine coastal and lagoon environments, to be included among the tools specified by Italian law D.Lgs. 152/2006.  相似文献   
996.
SUMMARY

This paper focuses on efforts to promote environmental education and community mobilization around environmental issues in Hong Kong. It is primarily concerned with efforts directed at the broader community (i.e. the population as a whole) rather than with environmental education through formal school and college curricula. The paper draws on a recently completed study commissioned by the Environmental Campaign Committee, the principal source of financial support for such efforts undertaken by environmental NGOs, community groups and educational institutions in Hong Kong. The study examined how and to what effect the Committee had used its financial resources between 1994–1999. It also examined international experience with a view to recommending changes in the overall approach to environmental education and community mobilization initiatives and their funding in Hong Kong.

The paper suggests that the existing approach to community-wide environmental education and its funding in Hong Kong have suffered from various weaknesses, most notably the absence of an integrated and goal-oriented strategy, an over-reliance on a ‘top-down’ campaign-based approach, a failure to establish explicit linkages with the concept of sustainable development and to ground initiatives at the local neighbourhood and community levels, and a preoccupation with the financial inputs provided to support this work at the expense of effective monitoring and auditing of project outputs and benefits.  相似文献   
997.
Asthma is a health condition that is also an environmental justice issue. Using an environmental justice frame, this paper explores socio-demographic, indoor hazard, and air quality factors that contribute to disparities in asthma hospitalizations. Multivariate Poisson regression models predicting asthma hospitalizations at the zip code level are employed to examine the case of metropolitan Phoenix, Arizona (AZ). Controlling for socio-demographics, indoor hazards, and toxic releases from industry, ozone was the strongest predictor of asthma hospitalizations. This paper contributes to the project of inserting health measures into quantitative environmental justice studies.  相似文献   
998.
Environmental federalism considers what level of government should optimally regulate pollution. This paper addresses this question for accidental pollution, which government regulates through the ex post liability regimes of either negligence or strict liability. We find that decentralizing the choice between these regimes does not, in general, induce the socially optimal outcome. When firms can pay all damages, all regions may choose negligence and impose an overly strict standard of due care. When firms may be bankrupted by damages, all regions may choose strict liability, which induces too little care. In addition, asymmetric equilibria are possible in which some regions choose negligence, others strict liability. Combining negligence with a Pigovian tax, or strict liability with a bonding requirement can align regional authorities' incentives with those of a central government.  相似文献   
999.
We analyze the potential for an environmental monitoring agency under different regulatory missions to use multiple measures of ambient pollution levels to induce firm compliance via endogenously determined probabilistic firm-level inspections of polluting activities. Departing from previous analyses, we consider a framework where the regulator has multiple, rather than a single, measures of ambient pollution in a setting where many firms are subject to a self-reported emissions tax that is not perfectly enforceable. Under a budget-driven mission, we show that a regulator can fruitfully utilize the added information from multiple ambient monitoring receptors to induce improved environmental compliance through the creation of strategic interactions among firms. Additionally, our results provide new evidence on the relative efficiency of budget- vs. target-driven environmental enforcement missions.  相似文献   
1000.
I analyze the pricing and investment behavior of a firm that signals the environmental attributes of its production technology through its price to uninformed environmentally conscious consumers. I then analyze the effect of change in environmental regulation on the signaling outcome and the firm's ex ante incentive to invest in cleaner technology. When regulation is weak, a firm signals cleaner technology through higher price; in this case, the firm earns lower profit when it has cleaner technology and thus, has no incentive to invest in cleaner technology. The price charged by the clean firm declines sharply beyond a critical level of regulation. When regulation is sufficiently stringent, the firm with cleaner technology charges lower price but earns higher signaling profit, and ex ante the firm has positive incentive to invest in cleaner technology. With weak regulation, the incentive of the firm to directly disclose its environmental performance rather than signal it through price is increasing in the level of regulation; the opposite holds when regulation is sufficiently stringent.  相似文献   
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