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191.
Craig P. Diamond 《环境质量管理》1995,5(2):9-23
Many anticipate that over the next decade, voluntary environmental management system (EMS) standards will take on the same importance in the marketplace as the ISO 9000 quality standards; the draft international EMS standard (ISO 14001) is on pace to be completed by mid-1996. In the United States, despite rapidly growing interest in EMS standards, most companies and regulatory agencies are uncertain about their potential benefits and about the process of developing an EMS. Case studies of EMS implementation, particularly in small and medium-sized companies, are needed to demonstrate the process and identify areas in which further EMS guidance is needed for environmental managers. This article presents seven case studies of EMS implementation in small, medium-sized, and large companies. Each company is participating in an EPA-sponsored Demonstration Project in which a variety of organizations are piloting the implementation of EMS standards (the project is being coordinated by NSF International, a not-for-profit company specializing in environmental and public health standards and certification). The case studies, written by the companies themselves, share experiences of EMS assessment, planning, and implementation, and discuss challenges that are special to particular industries. 相似文献
192.
Sustainability has become an increasingly used term, but what does it mean in terms of practice. This research will look at
the harvesting of captured stormwater for the irrigation of urban playing fields and what the implications are for catchment
hydrology, local community, and local council. This research aims to identify, understand and determine the catchment conditions
that may hinder the stormwater quality and quantity for capture and reuse, as well as determining whether the stormwater harvesting
will be sustainable. Research methods for this project will include systemic analysis in order to further investigate the
assumptions being made in the study.
Manly Golf Club has relied on groundwater extraction supplemented by potable supplies for irrigation, however potable supplies
are no longer available. It has been proposed to provide irrigation supplies from stormwater via onsite storage and groundwater
recharge. Monitored stormwater entering the Golf Course from the adjacent Cemetery Creek sub-catchment for pollutants, have
indicated that it may be suitable for irrigation with treatment and may reduce problems generated by overuse of groundwater.
The proposal will provide environmental benefit through reduced pollution loads being discharged directly to receiving waters
and cessation of use of potable supplies by the Club. Social and economic benefits are expected to be gained and will be monitored
as part of an ongoing research program. 相似文献
193.
Continuous Improvement can be applied to every business function, including environmental auditing. The benefits of customer focus and performance measurement are realized in a more efficient business system and a higher level of environmental compliance. Lockheed has successfully used Continuous Improvement principles in the development and implementation of its environmental auditing program, which are described in this article. 相似文献
194.
Few economic studies are available to measure off-highway vehicle recreation benefits foregone when trails must be closed to protect the environment. This paper estimates the non-market benefits associated with off-highway vehicle (OHV) recreation on National Forest lands in Larimer County, Colorado. We use a contingent valuation model (CVM) to estimate benefits to OHV users, which includes dirt bike riders, all terrain vehicle (ATV) riders, and 4-wheel drive (4 × 4) users. Using CVM we find the mean consumer surplus estimates to be $78 per person per day. These results are consistent with the few previous estimates of OHV recreation benefits. This equates to a per trail per summer consumer surplus of at least between $219,467 and $296,876, and a county level surplus per summer to be at least between $796,447 and $1,077,367. These benefits can be compared to environmental costs to obtain a more complete picture of the effects of trail closure, as well as the negative spillovers to non-motorized users. 相似文献
195.
Robert Dilmore Craig Griffith Zhu Liu Yee Soong Sheila W. Hedges Richard Koepsel Mohammad Ataai 《International Journal of Greenhouse Gas Control》2009,3(4):401-410
A novel CO2 separation concept is described wherein the enzyme carbonic anhydrase (CA) is used to increase the overall rate of CO2 absorption after which hydrated CO2 reacts with regenerable amine-bearing polyacrylamide buffering beads (PABB). Following saturation of the material's immobilized tertiary amines, CA-bearing carrier water is separated and recycled to the absorption stage while CO2-loaded material is thermally regenerated. Process application of this concept would involve operation of two or more columns in parallel with thermal regeneration with low-pressure steam taking place after the capacity of a column of amine-bearing polymeric material was exceeded. PABB CO2-bearing capacity was evaluated by thermogravimetric analysis (TGA) for beads of three acrylamido buffering monomer ingredient concentrations: 0 mol/kg bead, 0.857 mol/kg bead, and 2 mol/kg bead. TGA results demonstrate that CO2-bearing capacity increases with increasing PABB buffering concentration and that up to 78% of the theoretical CO2-bearing capacity was realized in prepared PABB samples (0.857 mol/kg recipe). The highest observed CO2-bearing capacity of PABB was 1.37 mol of CO2 per kg dry bead. TGA was also used to assess the regenerability of CO2-loaded PABB. Preliminary results suggest that CO2 is partially driven from PABB samples at temperatures as low as 55 °C, with complete regeneration occurring at 100 °C. Other physical characteristics of PABB are discussed. In addition, the effectiveness of bovine carbonic anhydrase for the catalysis of CO2 dissolution is evaluated. Potential benefits and drawbacks of the proposed process are discussed. 相似文献
196.
Sperm competition as a mechanism of female choice in the field cricket,Gryllus bimaculatus 总被引:9,自引:0,他引:9
L. W. Simmons 《Behavioral ecology and sociobiology》1987,21(3):197-202
Summary While traditionally viewed as an extension of intermale competition, mechanisms of sperm competition may be used by multiply mating females for mate choice. In the field cricket G. bimaculatus sperm were shown to mix in the spermatheca. The proportion of offspring sired by the second male increased with spermatophore attachment duration and, therefore, the number of sperm transferred. There was no second male advantage for single matings after an initial double mating. However, the proportion ofoffspring sired by the second male increased in proportion to the number of times he mated such that second males mating three times after an initial double mating had the advantage at fertilization. The data suggested that sperm were utilized in proportion to their numerical representation in the spermatheca. The mechanism of sperm precedence may, therefore, be one of sperm dilution. Female G. bimaculatus may control the degree of sperm competition as a mechanism of mate choice. By accepting large quantities of sperm from chosen males they may determine the paternity of their offspring by diluting out the sperm stored from previous matings. 相似文献
197.
John L. Craig 《Behavioral ecology and sociobiology》1984,14(2):147-150
Summary The prisoner's dilemma of game theory provides a possible explanation for communal breeding in the pukeko (Porphyrio porphyrio, Aves) where group breeding birds are at a reproductive disavantag compared to pairs. Territorial defence is largely the realm of males. A male who defect on neighbours by taking in an extra male defender and so becoming communal stands to gain territorial area and possibly higher reproductive success. Neighbours are forced to follow suit if additional males are available or lose their territory and therefore their breeding opportunities. If neighbours also admit an extra defender, the initial defector loses his advantages and all males end up with the lower breeding success of communal groups. Such defection to a communal habit appears to be the only stable solution. 相似文献
198.
Summary Seasonal variation in mean hind tibia length and mean testes length is investigated in the yellow dung fly, Scathophaga stercoraria (L.). There is a cycle in mean hind tibia length and mean testes length over a season. The body size curve peaks later than the testes length curve, showing that there is no fixed relationship between the two variables. The causes of variation in testes size and its influence on copula duration are experimentally examined. Increasing the number of Drosophila eaten per day leads to increased mature testes length. Males with larger testes copulate for longer than males with smaller ones, and smaller males copulate for longer than do larger males. While testes shrivel with successive copulas, copula duration remains constant. The more females a male is prepared to copulate with in a day (up to five), the longer he copulates with each. The shrinkage of the testes of males collected throughout a day suggests that males copulate with an average of 4 females per day. The costs of sperm production are thus shown to have a significant influence on the copula duration.Offprint requests to: P.I. Ward at the second address 相似文献
199.
Alec P. Christie Tatsuya Amano Philip A. Martin Silviu O. Petrovan Gorm E. Shackelford Benno I. Simmons Rebecca K. Smith David R. Williams Claire F. R. Wordley William J. Sutherland 《Conservation biology》2021,35(1):249-262
Efforts to tackle the current biodiversity crisis need to be as efficient and effective as possible given chronic underfunding. To inform decision-makers of the most effective conservation actions, it is important to identify biases and gaps in the conservation literature to prioritize future evidence generation. We used the Conservation Evidence database to assess the state of the global literature that tests conservation actions for amphibians and birds. For the studies in the database, we investigated their spatial and taxonomic extent and distribution across biomes, effectiveness metrics, and study designs. Studies were heavily concentrated in Western Europe and North America for birds and particularly for amphibians, and temperate forest and grassland biomes were highly represented relative to their percentage of land coverage. Studies that used the most reliable study designs—before-after control-impact and randomized controlled trials—were the most geographically restricted and scarce in the evidence base. There were negative spatial relationships between the numbers of studies and the numbers of threatened and data-deficient species worldwide. Taxonomic biases and gaps were apparent for amphibians and birds—some entire orders were absent from the evidence base—whereas others were poorly represented relative to the proportion of threatened species they contained. Metrics used to evaluate effectiveness of conservation actions were often inconsistent between studies, potentially making them less directly comparable and evidence synthesis more difficult. Testing conservation actions on threatened species outside Western Europe, North America, and Australasia should be prioritized. Standardizing metrics and improving the rigor of study designs used to test conservation actions would also improve the quality of the evidence base for synthesis and decision-making. 相似文献
200.
Aspects of transboundary, water shortage, and fisheries issues are discussed in the context of the recently completed Global International Waters Assessment (GIWA) for the Pacific Islands. The region encompasses some 30 million km2 and approximately 12% of the world's ocean space, and features great geographic, demographic and developmental diversity. Global change, especially sea level rise and sea surface temperature increases, is the dominant transboundary concern as it impacts all aspects of life. Water shortage and unsustainable fishing issues are selected for discussion, as they will dominate the region into the foreseeable future, and they are illustrated with examples from Fiji, Kiribati, and Tonga. The environmental impacts are exacerbated by socioeconomic issues such as high population growth rates, urban drift, the breakdown of traditional life styles and the rapid adoption of the cash economy. Policy options that may assist in addressing these issues are proposed. 相似文献