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61.
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
62.
63.
Jonn A. Foulk Wayne Y. Chao Danny E. Akin Roy B. Dodd Patricia A. Layton 《Journal of Polymers and the Environment》2004,12(3):165-171
Municipal solid wastes generated each year contain potentially useful and recyclable materials for composites. Simultaneously, interest is high for the use of natural fibers, such as flax (Linum usitatissimum L.), in composites thus providing cost and environmental benefits. To investigate the utility of these materials, composites containing flax fibers with recycled high density polyethylene (HDPE) were created and compared with similar products made with wood pulp, glass, and carbon fibers. Flax was either enzyme- or dew-retted to observe composite property differences between diverse levels of enzyme formulations and retting techniques. Coupling agents would strengthen binding between fibers and HDPE but in this study fibers were not modified in anyway to observe mechanical property differences between natural fiber composites. Composites with flax fibers from various retting methods, i.e., dew- vs. enzyme-retting, behaved differently; dew-retted fiber composites resulted in both lower strength and percent elongation. The lowest level of enzyme-retting and the most economical process produces composites that do not appear to differ from the highest level of enzyme-retting. Flax fibers improved the modulus of elasticity over wood pulp and HDPE alone and were less dense than glass or carbon fiber composites. Likely, differences in surface properties of the various flax fibers, while poorly defined and requiring further research, caused various interactions with the resin that influenced composite properties. 相似文献
64.
This article presents a review of in situ technologies for the remediation of soils contaminated with lead, zinc, and/or cadmium. The objective of this review is to assess the developmental status of the available in situ technologies and provide a general summary of typical applications and limitations of these technologies. The literature review identified seven in situ remediation technologies—solidification/stabilization, vitrification, electrokinetic remediation, soil flushing, phytoextraction, phytostabilization, and chemical stabilization. These technologies were considered for their ability to meet a specific set of remediation objectives under a range of conditions. Each of these technologies has both strengths and weaknesses for addressing particular remedial situations discussed in the article for each of the technologies. A general summary of which technologies are most applicable to common remedial scenarios is also provided. © 2004 Wiley Periodicals, Inc. 相似文献
65.
In 1995, the U.S. Environmental Protection Agency (US EPA) initiated the Brownfields Program to help local governments clean up and reuse hundreds of thousands of contaminated former factories and transportation and other commercial sites in cities and industrialized suburbs. By the end of 2002, the Brownfields Program had distributed grants of about $200,000 each to 436 local governments. Program grants have diffused through federal, state, regional, and local levels of government and private and not‐for profit organizations, and have reached into economically distressed neighborhoods. As expected, grant recipients disproportionately had a legacy of contaminated industrial sites and relatively large African American and/or Latino populations. But abandoned factories and environmental justice concerns do not completely explain the geographical distribution of recipients. Award winners tended to be larger cities with more capacity to compete for grants and were likely to be connected to sources of information about the grant opportunity and to decision makers. With a few exceptions, recipients consider the program to be highly successful at stimulating entrepreneurs to remediate and redevelop sites and, sometimes, surrounding neighborhoods. © 2005 Wiley Periodicals, Inc. 相似文献
66.
Crop soils, ditch sediments, and water flowing from several farm areas to salmon tributary streams of the Fraser River in the Lower Fraser Valley (LFV) of British Columbia, Canada, were sampled in 2002-2003 to quantify for residues of an organochlorine cyclodiene pesticide, endosulfan (END = alpha-endosulfan + beta-endosulfan + endosulfan sulfate). Residues from historical use of other selected organochlorine pesticides, namely, cyclodienes (aldrin, alpha-chlordane, gamma-chlordane, dieldrin, endrin, endrin aldehyde, heptachlor, and heptachlor epoxide), hexachlorocyclohexanes [alpha-benzene-hexachloride (alpha-BHC), beta-BHC, delta-BHC, and gamma-BHC (lindane)], and DDT-related compounds (p,p-DDT, p,p-DDD, p,p-DDE, and methoxychlor) were also determined. Reference and background levels of these pesticides in ditches leading to fish streams were obtained from pristine watershed areas. Varying amounts of END residues were detected in soils (<0.02-5.60 mg kg(-1) dry wt.) and ditch sediments (<0.02-3.33 mg kg(-1) dry wt.) in mainly three of five farm areas sampled. Likewise, residues (excluding END) of other selected organochlorine compounds such as aldrin, BHC, chlordane, endrin, p,p-DDT, methoxychlor, and their respective major transformation products (endosulfan sulfate, dieldrin, endrin aldehyde, heptachlor, heptachlor epoxide, p,p-DDD, and p,p-DDE) were found in crop soils (<0.02-16.2 mg kg(-1) dry wt.) and sediments (<0.02-9.73 mg kg(-1) dry wt.). Most of these pesticides (END: <0.01-1.86 microg L(-1); other selected organochlorine pesticides: <0.0.1-1.50 microg L(-1)) were also found in ditch water leading to salmon streams in several farms. The END levels of crop soils from the same LFV study farms in 1994 and 2003 indicated an estimated decline of 22% to 1.35 mg kg(-1) dry wt. during that period. This reduction was probably due to the increasing use of alternate pesticides (e.g., organophosphorus compounds). Some possible biological implications of these pesticide residues on nontarget organisms in the LFV are discussed. 相似文献
67.
David Brandes Gregory J. Cavallo Michael L. Nilson 《Journal of the American Water Resources Association》2005,41(6):1377-1391
Rapid land development is raising concern regarding the ability of urbanizing watersheds to sustain adequate base flow during periods of drought. Long term streamflow records from unregulated watersheds of the lower to middle Delaware River basin are examined to evaluate the impact of urbanization and imperviousness on base flow. Trends in annual base flow volumes, seven‐day low flows, and runoff ratios are determined for six urbanizing watersheds and four reference watersheds across three distinct physiographic regions. Hydrograph separation is used to determine annual base flow and stormflow volumes, and nonparametric trend tests are conducted on the resulting time series. Of the watersheds examined, the expected effects of declining base flow volumes and seven‐day low flows and increasing stormflows are seen in only one watershed that is approximately 20 percent impervious and has been subject to a net water export over the past 15 years. Both interbasin transfers and hydrologic mechanisms are invoked to explain these results. The results show that increases in impervious area may not result in measurable reductions in base flow at the watershed scale. 相似文献
68.
DENNIS D. COX LAWRENCE H. COX KATHERINE B. ENSOR 《Environmental and Ecological Statistics》1997,4(3):219-233
In this paper we summarize research issues for spatial environmental sampling stemming from a NISS/USEPA workshop held on 21-22 September 1994 at Chapel Hill, NC. 相似文献
69.
Ryden JC Whitehead DC Lockyer DR Thompson RB Skinner JH Garwood EA 《Environmental pollution (Barking, Essex : 1987)》1987,48(3):173-184
Emissions of ammonia were measured from livestock excreta and fertilisers applied to grass swards, from grazed paddocks, from decomposing grass herbage and from an animal house containing dairy cows. Emissions from urine, dung, slurry and fertilisers were determined using a system of wind tunnels with each tunnel covering an area of 1 m(2). Emissions from grazed swards were determined using a micrometeorological mass balance method. From the results of these measurements, together with other published information, an inventory for ammonia emissions has been calculated for grassland and livestock production systems over the UK as a whole. It is estimated that emissions from grassland and cattle and sheep production amount to about 230 kt NH(3)-N annually, while emissions from pig and poultry production amount to about 40 kt and 80 kt NH(3)-N, respectively. 相似文献
70.
Jones GL Willy D Lumsden B Taufa T Lourie J 《Environmental pollution (Barking, Essex : 1987)》1987,48(2):101-115
It has long been known that mining activity can markedly change the level and distribution of certain heavy metals in the adjacent environment. This pollution can be quite widespread and long lasting and often has deleterious effects on the health of local populations. In the present study scalp hair was used as the biopsy material because of its ease of collection and long history of use in this connection. Hair was collected from all the local villages in the vicinity of the mine site, as well as from Papua New Guinean nationals from other provinces, and European expatriates who were employed by the mining company and who were resident in the area. Hair from local people showed a remarkably high iron content by comparison with previously studied populations. The extreme variations in hair iron levels were reflected in the differential distribution of levels according to location, age and sex. Hair cadmium was also high in the population studied. Hair copper, lead, zinc and mercury all appeared to be within 'normal' limits by comparison with other general populations. These results are discussed in the context of the environmental and social impact of the mining operations on the local people. 相似文献