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461.
This paper assesses the status of coastal zones in the context of expected climate change and its related impacts, as well as current and future socioeconomic pressures and impacts. It is argued that external stresses and shocks relating to sea-level rise and other changes will tend to exacerbate existing environmental pressures and damage in coastal zones. Coastal zones are under increasing stress because of an interrelated set of planning failures including information, economic market, and policy intervention failures. Moves towards integrated coastal zone management are urgently required to guide the coevolution of natural and human systems. Overtly technocentric claims that assessments of vulnerability undertaken to date are overestimates of likely future damages from global warming are premature. While it is the case that forecasts of sea-level rise have been scaled down, much uncertainty remains over, for example, combined storm, sea surge, and other events. In any case, within the socioeconomic analyses of the problem, resource valuations have been at best only partial and have failed to incorporate sensitivity analysis in terms of the discount rates utilized. This would indicate an underestimation of potential damage costs. Overall, a precautionary approach is justified based on the need to act ahead of adequate information acquisition, economically efficient resource pricing and proactive coastal planning. 相似文献
462.
Corporations own approximately 25% of all private land in the United States and, therefore, play an essential role in protecting biodiversity and maintaining natural habitats. The Wildlife Habitat Council (WHC) is a unique joint venture between conservation organizations and corporations to utilize corporate lands for ensuring biodiversity. The following case studies demonstrate how corporations have helped ensure healthy ecosystems and provided critical leadership in regional efforts. Amoco Chemical Company's Cooper River Plant has been instrumental in developing a cooperative project that involves numerous corporations, plantation owners, private citizens, nonprofit organizations, government agencies, and community groups to develop a comprehensive, ecosystem-based management plan for part of the Cooper River in Charleston, South Carolina, USA. The second case focuses on the Morie Company, a national sand quarry operator headquartered in southern New Jersey, USA. Morie Company is working with WHC, community groups, the Pinelands Commission, and other state regulatory agencies to explore sustainable development opportunities for companies within the Pinelands regulations. The third case takes us to DuPont Company's Asturias, Spain, site. A win—win success story of improved habitat and cost savings is the result of DuPont's concern for the environment, ability to work with a variety of groups, and willingness to consider innovative restoration techniques. The fourth case discusses Consumers Power Company's Campbell Plant in West Olive, Michigan, USA. In addition to implementing projects that contribute to biodiversity, Consumers Power has developed an environmental education field station to teach others about the importance of natural habitats. The final case highlights Baltimore Gas & Electric Company's efforts to maintain habitat for endangered species at their Calvert Cliffs site in Maryland. 相似文献
463.
Allan K Fitzsimmons 《Journal of the American Water Resources Association》1996,32(2):217-227
ABSTRACT: Protection of ecosystems as entities on the landscape has attracted a wide range of support. Ecosystem-based public policies are claimed to be more effective, efficient, and scientifically sound than other approaches to environmental and natural resource policy. The ecosystem concept was never intended to serve as a public policy guide or to determine landscape units for land management purposes. This paper critically examines the use of the ecosystem concept in public policy and land use management and analyzes the proposed rule to manage the National Forest System according to ecosystem management principles. The concept is found to be unsuitable as a basis for guiding environmental and natural resource public policies in general while the proposed rule to manage the national forests according to ecosystem management principles is shown to be incoherent. 相似文献
464.
Activated carbon, developed from fertilizer waste, has been used for the removal of Hg2+, Cr6+, Pb2+, and Cu2+. Mass transfer kinetic approach has been successfully applied for the determination of various parameters necessary for designing a fixed-bed absorber. Parameters selected are the length of the (PAZ) primary adsorption zone (δ), total time involved for the establishment of primary adsorption zone (tx), mass rate of flow to the absorber (Fm), time for primary adsorption zone to move down its length (tδ), amount of adsorbate adsorbed in PAZ from breakpoint to exhaustion (Ms), fractional capacity (f), time of initial formation of PAZ (tf) and per cent saturation of column at break point. Chemical regeneration has been achieved with 1 M HNO3. 相似文献
465.
There are numerous technologies currently being tested by EPA, universities throughout the world, and private research organizations. A few of the more promising innovative technologies as well as fully tested and proven remedies for treating contaminated groundwater are presented in this article. Although several of those technologies have been in existence for only four to five years, the results of full-scale testing are being produced. The method for each of these promising technologies is described, results from recent field-scale studies are summarized, and a discussion of cost is presented. 相似文献
466.
Characteristics of large cooking oil pool fires and their extinguishment by water mist 总被引:1,自引:0,他引:1
Z. Liu D. Carpenter A.K. Kim 《Journal of Loss Prevention in the Process Industries》2006,19(6):516-526
Large cooking oil pool fires, occurring in industrial oil cookers, present a severe hazard to food processing plants due to their size and the large amount of hot oil involved. This paper reports a series of full-scale fire experiments conducted in a large industrial oil cooker mock-up. The characteristics of large cooking oil pool fires and the effect of oil depth and hood position in the oil cooker on fire growth were studied. The use of water mist for extinguishing large oil pool fires and their extinguishing performance under different discharge pressure and with different types of water mist systems were investigated. Experimental results showed that the cooking oil underwent a substantial expansion in volume during heating. The fires developed quickly once the oil auto-ignited. The fire growth rate was affected by the oil depth in the pan and the hood position in the oil cooker. The water mist fire suppression systems effectively extinguished large cooking oil fires and prevented them from re-igniting. Their extinguishing performance was determined by the type of water mist system, discharge pressure and hood position in the oil cooker. 相似文献
467.
Explosive gas mixtures and explosive dust clouds, once existing, exhibit similar ignition and combustion features. However, there are two basic differences between dusts and gases which are of substantially greater significance in design of safety standards than these similarities. Firstly, the physics of generation and up-keeping of dust clouds and premixed gas/vapour clouds are substantially different. This means that in most situations where accidental explosive gas clouds may be produced quite readily, generation of explosive dust clouds would be highly unlikely. Secondly, contrary to premixed gas flame propagation, the propagation of flames in dust/air mixtures is not limited only to the flammable dust concentration range of dynamic clouds. The state of stagnant layers/deposits offers an additional discrete possibility of flame propagation.
The two European Directives 94/9/EC (1994) and 1999/92/EC (1999) primarily address gases/vapours, whereas the particular properties of dusts are not addressed adequately. Some recent IEC and European dust standards resulting from this deficiency are discussed, and the need for revising the two directives accordingly is emphasized. 相似文献
468.
Biswajit Ruj Imranur Rehman A.K. Bandyopadhya 《Journal of Loss Prevention in the Process Industries》2006,19(6):645-647
After Bhopal disaster, emergency planning in an industrial area has become inevitable. The off-site emergency plan is an integral part of any major hazard control system. Boiling Liquid Expanding Vapour Explosion (BLEVE) leads to fatal consequences. This paper highlights some salient features of the emergency scenario, which ultimately leads to fireball with enormous pressure wave all around. 相似文献
469.
Jiří Pšeja Josef Hrnčiřík Jan Kupec Hana Charvátová Petr Hruzík Michael Tupý 《Journal of Polymers and the Environment》2006,14(3):231-237
Biodegradability testing was performed in an aqueous environment under anaerobic conditions after inoculation with digested sludge from municipal wastewater treatment plant. In cross-linking with 1,2:3,4-diepoxybutane in limits 0.8–9.1% weight, biodegradability degree decreased from 76.8 to 62.2%; when 1,2:7,8 diepoxyoctane in quantities 1.1–13.2% weight was used, biodegradability degree dropped more prominently – from 72.3 to 22.8%. There is obviously a direct connection between growing cross-link degree (assessed by so-called fixation index) and decreasing readiness to biodegradation, apparently owing to build-up of a network forming an obstacle to access of micro-organisms and enzymes. 相似文献
470.
The New Jersey Toxics Reduction Workplan for Ny-Nj Harbor: Distribution of Pcdd/Fs in Ambient Waters
As part of the NJ Toxics Reduction Workplan for NY-NJ Harbor, ambient water samples were collected at fifteen locations along
the tidal portions of the Hackensack, Passaic, Raritan, Rahway and Elizabeth Rivers, and in Newark Bay, the Arthur Kill, and
Kill van Kull. A Trace Organics Platform Sampler was used to collect a total of 75 suspended sediment phase samples between
June 2000 and May 2002. These samples were analyzed for spatial and wet vs. dry weather trends in the 17 polychlorinated dibenzo-p-dioxins
and dibenzofurans (PCDD/Fs; modified USEPA Method 1613b). Mean total PCDD/F (tPCDD/F) concentrations at the sampling locations
ranged between 3.8 and 41.5 ng/g. On average, OCDD accounted for almost 80% of the tPCDD/F concentrations; mean total [PCDD/F
– OCDD] concentrations ranged between 0.84 and 5.20 ng/g at the sampling locations. Mean 2,3,7,8-TCDD concentrations ranged
between 0.003 and 0.28 ng/g, with the highest concentrations (> 0.10 ng/g) along the tidal Passaic and lower Hackensack Rivers,
and in upper Newark Bay. Mean tPCDD/F Toxic Equivalency Quotients (TEQ) ranged between 45 and 344 TEQ pg/g, with the highest
levels found in the lower Passaic River. Toxicity was primarily driven by 2,3,7,8-TCDD concentrations in the Passaic and Hackensack
Rivers, and in Newark Bay. Examples of congener distribution patterns at some of the sampling locations are also presented. 相似文献