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31.
This article introduces the concept of ISO 14001 registration, outlines related assessment processes, and reviews the drivers behind developing an ISO-14001-concordant environmental management system (EMS) and seeking third party registration of that EMS. It focuses on registration strategies for larger organizations and considerations in choosing a registrar, including: auditor qualifications, standards for the conduct of EMS audits, and some issues for audit and registration service providers. The authors conclude that it is beneficial to pursue an ISO-14001-concordant EMS and that the value of the system can be enhanced through registration. However, some thought should be given to choosing the appropriate registrar, in particular to their EMS and audit approaches and to the qualifications of their audit team. Service providers are also cautioned to remember that ISO 14001 is not the same as ISO 9000, and that the registrar's standard of care in the discharge of their work should reflect that. © 1998 John Wiley & Sons, Inc.  相似文献   
32.
Monthly samples were collected in oceanic waters off Discovery Bay, Jamaica, in 60- and 200-m vertical hauls, using 200- and 64-m mesh plankton nets, from June 1989 to July 1991. Sixty-nine species of copepods were identified: nauplii, copepodites and adults were separately enumerated. Total copepod abundances (all stages) ranged from 695 to 4120 m-3 in the upper 60 m, and from 483 to 3319 m-3 in the 200-m water column, without any clear seasonal pattern. With the exception of temperature, no seasonal variations in physico-chemical (chlorophyll a, S, particulate organic carbon, particulate protein) or biological variables were evident. Nauplii, adults and copepodites of selected taxa, and two chaetognath species, showed no significant variations in body length. Significant variantions in reproductive index were detected for several species, but without seasonal trends; many species appear to be continuous or intermittent breeders. There was no evidence of seasonal pattern in overall community composition or diversity, or evidence of changes due to water mass advection. The copepod community can be divided into a recurrent group of 13 (at 60 m) to 17 (at 200 m) perennial species, present year-round, and associated ephemeral groups of 1 to 3 species, present randomly for 1 to 4 consecutive months. The most plausible explanation of these patterns is that broad areas of the Caribbean Sea are dominated by the community of perennial species, while the ephemeral species represent the superimposed influence of local mesoscale gyres.  相似文献   
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Motivated by shallow ocean waves propagating over coral reefs, we investigate the drift velocities due to surface wave motion in an effectively inviscid fluid that overlies a saturated porous bed of finite depth. Previous work in this area either neglects the large-scale flow between layers (Phillips in Flow and reactions in permeable rocks, Cambridge University Press, Cambridge, 1991) or only considers the drift above the porous layer (Monismith in Ann Rev Fluid Mech 39:37–55, 2007). Overcoming these limitations, we propose a model where flow is described by a velocity potential above the porous layer and by Darcy’s law in the porous bed, with derived matching conditions at the interface between the two layers. Both a horizontal and a novel vertical drift effect arise from the damping of the porous bed, which requires the use of a complex wavenumber k. This is in contrast to the purely horizontal second-order drift first derived by Stokes (Trans Camb Philos Soc 8:441–455, 1847) when working with solely a pure fluid layer. Our work provides a physical model for coral reefs in shallow seas, where fluid drift both above and within the reef is vitally important for maintaining a healthy reef ecosystem (Koehl et al. In: Proceedings of the 8th International Coral Reef Symposium, vol 2, pp 1087–1092, 1997; Monismith in Ann Rev Fluid Mech 39:37–55, 2007). We compare our model with field measurements by Koehl and Hadfield (J Mar Syst 49:75–88, 2004) and also explain the vertical drift effects as documented by Koehl et al. (Mar Ecol Prog Ser 335:1–18, 2007), who measured the exchange between a coral reef layer and the (relatively shallow) sea above.

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Abstract: The purpose of this study was to validate the application of an invertebrate community index (ICI) to assess the biological integrity of urban streams. Validation involved comparing chemical and habitat data to ICI scores from 20 urban streams and four least‐impacted streams in the Choctawhatchee and Pea River watersheds located in Southeast Alabama. Chemical and habitat data were collected to support whether the ICI accurately predicts the health of the streams. A significant difference between urban and least‐impacted ICI scores, habitat evaluation scores, chemical variables, taxa richness, and Shannon‐Wiener diversity were observed when urban sites were compared with least‐impacted sites using Mann‐Whitney U‐test. Urban sites having low ICI scores, low species richness and diversity, and poor habitat showed greater impairment than least‐impacted sites. Cluster analysis of macroinvertebrate assemblages indicated two clusters. Significant differences between clusters in habitat evaluations, chemical parameters, and ICI scores showed that some urban sites were more degraded than other urban sites in the study. Differentiation between least‐impacted and urban sites indicated that the ICI provided valid biotic assessments. Therefore, this study validated that the ICI is capable of predicting the biological integrity of urban streams in the Choctawhatchee and Pea River watersheds.  相似文献   
37.
Rural industries and water pollution in China   总被引:10,自引:0,他引:10  
Water pollution from small rural industries is a serious problem throughout China. Over half of all river sections monitored for water quality are rated as being unsafe for human contact, and this pollution is estimated to cost several per cent of GDP. While China has some of the toughest environmental protection laws in the world, the implementation of these laws in rural areas is not effective. This paper explains the reasons for this implementation gap. It argues that the factors that have underpinned the economic success of rural industry are precisely the same factors that cause water pollution from rural industry to remain such a serious problem in China. This means that the control of rural water pollution is not simply a technical problem of designing a more appropriate governance system, or finding better policy instruments or more funding. Instead, solutions lie in changes in the model that underpins rural development in China.  相似文献   
38.
A model is presented of liquid flow under gravity, over horizontal and sloping surfaces, based on the Shallow Water Equations. The aim is to facilitate assessment of the efficacy of bunds surrounding liquid storage tanks, in cases where the liquid front encountering the bund carries significant momentum. The model, called SPLOT, incorporates terms representing the effects of turbulent and laminar friction, and a sub-model for the effect of vertical walls. Having produced a robust numerical solution method, and verified its performance in cases where analytic solutions are known, it is the objective of this work to test the model’s validity against experimental data on flows overtopping bunds. SPLOT is found to be very satisfactory in a wide range of circumstances involving both vertical and sloping bunds. Physical reasons are identified for the overly conservative predictions found in the remaining cases, and a simple parameter is derived which indicates whether the model is being used outside its range of optimum validity.  相似文献   
39.
Toronto is among the fastest-growing urban regions in North America. Regional efforts to preserve rural landscapes and remnant habitat have had variable success. In the 1990s, significant conflict emerged over proposals to build large housing developments on portions of the Oak Ridges Moraine, a 160-km stretch of environmentally sensitive land along the city’s northern edge. After years of planning conflict, Ontario’s provincial government created the Oak Ridges Moraine Conservation Plan, an Act of the Ontario Legislature. The Plan represents a dramatic change in Ontario’s approach to conservation planning. We examine the development and implementation of the Conservation Plan as an example of environmental planning policy in a complex urban setting. Data from interviews with policy actors, planning agency documents, and geospatial sources are used to construct an analysis and discussion of the Plan and its implementation. From a policy research perspective, the evolution and implementation of the Plan require analysis and monitoring to better understand how such approaches can best be implemented. The Conservation Plan marks a change in policy in Ontario, and the implementation process highlights challenges in putting conservation plans into practice.  相似文献   
40.
Monthly samples were collected in oceanic waters off Discovery Bay, Jamaica, in 60- and 200-m vertical hauls, using 200- and 64-m mesh plankton nets, from June 1989 to July 1991. Length-weight regressions were derived for twelve genera of copepods (R2=0.79 to 0.97). For eight occasions spanning the study period, biomass estimates generated from these length-weight regressions differed by only 3% from direct weight determinations. The mean ash content of copepods was 7.1%, and the energy density was 20.8 kJ g-1 ash-free dry weight (AFDW). Mean annual biomass of the total copepod community in the upper 60 m was 1.83 mg AFDW m-3 (range 1.14 to 2.89 mg AFDW m-3), and for the 200-m water column was 0.96 mg AFDW m-3 (range 0.12 to 1.99 mg AFDW m-3). Estimates of generation times for five common taxa ranged from 16.1 to 33.4 d. None of the taxa investigated displayed isochronal development; in general, stage duration increased in later copepodite stages. Weight increments showed a significant decrease in later copepodite stages, but with strong reversal of the trend from stage 5 to adult female in most species. Daily specific growth rates also declined in later copepodite stages, and ranged from 1.49 d-1 in stage 1–2 Paracalanus/Clausocalanus spp. to 0.04 in stage 5-female of Oithona plumifera. Progressive food limitation of somatic copepodite growth and egg production is postulated. Naupliar production was 50.4 to 59.5% of copepodite production, and egg production was 35.1 to 27.7% of copepodite production in the 60-and 200-m water columns, respectively. Total annual copepod production, including copepodites, nauplii, eggs and exuviae, was 160 kJ m-2 yr-1 for the upper 60 m and 304 kJ m-2 yr-1 for the upper 200 m. Secondary production of the copepod community in oceanic waters off Discovery Bay approaches 50% of the corresponding value in tropical neritic waters.  相似文献   
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