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Development of a marina in a flooded brownstone quarry will require construction of a canal to the Connecticut River through an isthmus separating the two systems. An environmental audit over a 16-month period developed quantitative limnological data required by regulatory agencies. The deep quarry basin, protected by high sandstone walls, became strongly stratified in summer. Development of littoral vegetation in the quarry was prevented by the steep sides of the basin. Unusual characteristics of the manmade quarry basin, compared to most natural lakes in Connecticut, included a mean depth of 14 m, an intense thermocline, and negative heterograde oxygen profiles with metalimnetic minima. Alkalinity, conductivity, and nutrient levels differed significantly between the quarry and the river. Mean chlorophyll a concentrations in the two systems were similar, but the distribution of phytoplankton classes were quite different. The environmental audit, by comparing physical, chemical, and biological characteristics of the quarry to those of the river, allowed prediction of changes in trophic status when the two systems are joined.  相似文献   
2.
新<海洋环境保护法>与有关国际公约的实施   总被引:3,自引:0,他引:3  
概述了新《海洋环境保护法》与《73/ 78防污公约》、《1990年国际油污防备、反应和合作公约》、《1992年国际油污损害民事责任公约》等有关国际防污公约相关条款的相互关系及其实施  相似文献   
3.
Cumulative impact of marinas on estuarine water quality   总被引:1,自引:0,他引:1  
The purpose of this work is to present a modeling approach for assessing and managing the cumulative impact of marinas on estuarine systems. In doing so, both a water-quality model and a planning and management model are developed. The water-quality model predicts biochemical oxygen demand (BOD) and fecal coliform (FC) loadings from marina sources in a hypothetical North Carolina estuary. By running the water-quality model repeatedly with varied loading input, impact coefficients are determined. These impact coefficients are used in the planning and management model, the output of which gives the sizes and locations of marinas in the estuarine system such that dissolved oxygen (DO) and FC water-quality standards are maintained.Five different estuarine development scenarios are considered. Each scenario is evaluated with respect to both maximum and uniform land development constraints. In addition, two alternative fecal coliform standards are used with each of the development options.  相似文献   
4.
By 2004, Belize was exhibiting classic fishing down of the food web. Groupers (Serranidae) and snappers (Lutjanidae) were scarce and fisheries turned to parrotfishes (Scarinae), leading to a 41% decline in their biomass. Several policies were enacted in 2009–2010, including a moratorium on fishing parrotfish and a new marine park with no-take areas. Using a 20-year time series on reef fish and benthos, we evaluated the impact of these policies approximately 10 years after their implementation. Establishment of the Southwater Caye Marine Reserve led to a recovery of snapper at 2 out of 3 sites, but there was no evidence of recovery outside the reserve. Snapper populations in an older reserve continued to increase, implying that at least 9 years is required for their recovery. Despite concerns over the feasibility of banning parrotfish harvest once it has become a dominant fin fishery, parrotfishes returned and exceeded biomass levels prior to the fishery. The majority of these changes involved an increase in parrotfish density; species composition and adult body size generally exhibited little change. Recovery occurred equally well in reserves and areas open to other forms of fishing, implying strong compliance. Temporal trends in parrotfish grazing intensity were strongly negatively associated with the cover of macroalgae, which by 2018 had fallen to the lowest levels observed since measurements began in 1998. Coral populations remained resilient and continued to exhibit periods of net recovery after disturbance. We found that a moratorium on parrotfish harvesting is feasible and appears to help constrain macroalgae, which can otherwise impede coral resilience.  相似文献   
5.
Marinas are usually located in coastal waters, but can also be found in lakes and rivers. Due to the activities that take place in marinas various contaminants are discharged. Specific measures have to be taken in order to keep the marina environment clean and healthy. Experiences from developed countries have shown that the most effective way to reduce pollution in marinas is the implementation of waste management programs. To this end, ‘Best Waste Management Programs’ (BWMPs) have been employed in the USA and other countries. However, in developing countries lack of available financial resources and unawareness of the concept of clean marinas may hinder the activities towards the application of BWMPs. The aim of this study is to address BWMPs in general and explain waste sources and disposal methods for marinas and yachting activities. The Kusadasi Setur marina in Turkey is investigated particularly as an example of a marina in a developing country and management measures taken in this marina are evaluated. The various kinds of waste generated in the marina are described and preventive measures against pollution taken in the marina are reviewed. Finally the importance of management programs towards the mitigation of pollution problems is emphasized.  相似文献   
6.
Macroalgal invasions in coastal areas have been a growing concern during the past decade. The present study aimed to assess the role of hull fouling on recreational yachts as a vector for macroalgal introductions. Questionnaire and hull surveys were carried out in marinas in France and Spain. The questionnaires revealed that the majority of yacht owners are aware of seaweed introductions, usually undertake short range journeys, dry dock their boat at least once a year, and use antifouling paints. The hull survey showed that many in-service yachts were completely free of macroalgae. When present, fouling assemblages consisted mainly of one to two macroalgal species. The most commonly found species was the tolerant green seaweed Ulva flexuosa. Most of the other species found are also cosmopolitan and opportunistic. A few nonnative and potentially invasive Ceramiales (Rhodophyta) were found occasionally on in-service yachts. On the basis of the information gathered during interviews of yacht owners in the surveyed area, these occurrences are likely to be uncommon. However they can pose a significant risk of primary or secondary introductions of alien macroalgal species, especially in the light of the increase in yachting activities. With large numbers of recreational yachts and relatively rare occurrences of nonnative species on hulls, comprehensive screening programs do not seem justified or practical. The risks of transferring nonnative species may, however, be minimized by encouraging the behaviors that prevent fouling on hulls and by taking action against neglected boats before they can act as vectors.  相似文献   
7.
Escherichia coli and total coliforms in water and sediments at lake marinas   总被引:2,自引:0,他引:2  
Escherichia coli, a fecal coliform, and total coliforms were monitored between September 1999 and October 2001 in five marinas at Lake Texoma, located on the Oklahoma and Texas border. The general trend was that densities of E. coli were lower in the summer season due to the lower loading of fecal material into Lake Texoma and the ecological conditions of the lake, such as more vigorous grazing by protozoa and less viability of E. coli at an elevated temperature. The densities of total coliforms greatly increased in the summer. E. coli levels increased with depth, and the bottom water samples had higher densities of E. coli mainly due to their association with particles. There was a direct relationship between amount of gasoline sold, which was related to recreational boating activity, and the resuspension of E. coli. This indicated that recreational boating activity in lake marinas may have resuspended bottom sediments with bound E. coli, and the presence of E. coli in marinas was not an indication of recent fecal contamination. E. coli were detected in the largest densities at the boat dock points, followed by the gasoline filling station, and marina entrance. In addition, enumeration of bacteria in bottom sediment showed that the densities of E. coli and total coliforms in sediment were much higher compared to those in lake water.  相似文献   
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