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541.
The presence of natural organic matter (NOM) strongly impacts drinking water treatment, water quality, and water behavior during distribution. Dissolved organic carbon (DOC) concentrations were determined daily over a 22 month period in river water before and after conventional drinking water treatment using an on-line total organic carbon (TOC) analyzer. Quantitative and qualitative variations in organic matter were related to precipitation and runoff, seasons and operating conditions. Following a rainfall event, DOC levels could increase by 3.5 fold over baseflow concentrations, while color, UV absorbance values and turbidity increased by a factor of 8, 12 and 300, respectively. Treated water DOC levels were closely related to the source water quality, with an average organic matter removal of 42% after treatment.  相似文献   
542.
Environmental Science and Pollution Research - Microplastics accumulation on beaches raises a serious concern worldwide. Hence, the present study was conducted with the focus of investigating the...  相似文献   
543.
Policy tools that allow for the coordination of various authorities at different levels of government are important for coastal protected areas. Frequently, multiple authorities manage these areas with varied and sometimes conflicting goals. This study examines a regulatory model implemented on the Cape Cod National Seashore in the US that uses federally-approved zoning to regulate private uses for protection of natural coastal resources. Local authorities implement the zoning which is designed to support national resource protection goals making this a prime model of cross-level governance for conservation. I use case study analysis to evaluate the program’s effectiveness by focusing on implementation and compliance in the context of multi-jurisdictional (i.e., national to local) relations. The analysis and subsequent discussion highlight the difficulties associated with implementation of intergovernmental mandates. Also, theoretical perspectives on compliance give insights about the implementation challenges of this model. The model’s limitations have implications for policymakers considering similar schemes implemented by split and hierarchical authorities with different, and possibly conflicting, coastal management goals.
Michelle PortmanEmail:
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544.
The conservation community increasingly views the corporate sector as a positive force for conservation. Collaborations between corporations and nongovernmental conservation organizations (NGOs) seek to mitigate the negative effects of corporate activities and augment positive conservation outcomes. I reviewed the establishment of corporate social responsibility (CSR) policies by corporations; the emerging focus on environmental practices and sustainability; and the history of engagement between corporations and nongovernmental organizations. I considered the ethical and reputation vulnerabilities of these collaborations, which depend especially on the financial nature of the relationship and reviewed how CSR approaches have influenced corporate practices. I concluded that whereas CSR practices can act to mitigate negative environmental impact, to date they have had limited positive effect on biodiversity conservation. Intereses Comunes y Conflictivos en los Compromisos entre Organizaciones y Corporaciones de Conservación  相似文献   
545.
Manifold linkages exist between climate change and sustainable development. Although these are starting to receive attention in the climate exchange literature, the focus has typically been on examining sustainable development through a climate change lens, rather than vice versa. And there has been little systematic examination of how these linkages may be fostered in practice. This paper examines climate change through a sustainable development lens. To illustrate how this might change the approach to climate change issues, it reports on the findings of a panel of business, local government, and academic representatives in British Columbia, Canada, who were appointed to advise the provincial government on climate change policy. The panel found that sustainable development may offer a significantly more fruitful way to pursue climate policy goals than climate policy itself. The paper discusses subsequent climate change developments in the province and makes suggestions as how best to pursue such a sustainability approach in British Columbia and other jurisdictions.  相似文献   
546.
The landscape of the conterminous United States has changed dramatically over the last 200 years, with agricultural land use, urban expansion, forestry, and other anthropogenic activities altering land cover across vast swaths of the country. While land use and land cover (LULC) models have been developed to model potential future LULC change, few efforts have focused on recreating historical landscapes. Researchers at the US Geological Survey have used a wide range of historical data sources and a spatially explicit modeling framework to model spatially explicit historical LULC change in the conterminous United States from 1992 back to 1938. Annual LULC maps were produced at 250-m resolution, with 14 LULC classes. Assessment of model results showed good agreement with trends and spatial patterns in historical data sources such as the Census of Agriculture and historical housing density data, although comparison with historical data is complicated by definitional and methodological differences. The completion of this dataset allows researchers to assess historical LULC impacts on a range of ecological processes.  相似文献   
547.
Government agencies responsible for pest animal management often assume that their views and assumptions about the benefits of control are widely shared, especially if these pests are exotics. This was certainly the case when tens of thousands of feral Asian water buffalo (Bubalus bubalis) were to be culled in Australias Kakadu National Park as part of a national Brucellosis and Tuberculosis Eradication Campaign (BTEC). Implementation of the campaign sparked considerable dispute between officials and aboriginal and non-aboriginal interests about the risks posed by buffalo relative to their value as a potential resource. Drawing upon a variety of written and oral sources relating to the era of buffalo control in Kakadu, this paper critically analyzes the way in which detriment caused by buffalo was appraised and managed under the BTEC program. In particular, the paper focuses the ways in which the BTEC program affected aboriginal people in Kakadu, who view buffalo as a source of customary and economic benefit as well as a source of change on their lands. The paper then considers what lessons can be learned from the BTEC for the development of sensible feral management objectives and strategies. It is argued that effective management of feral animals such as buffalo will require environmental managers to engage with local people and involve them in the definition and management of pest animal damage and methods of control.  相似文献   
548.
Sexual harassment studies in insects suggest that females can incur several kinds of costs from male harassment and mating. Here, we examined direct and indirect costs of male harassment on components of female fitness in the predominantly monandrous mosquito Aedes aegypti. To disentangle the costs of harassment versus the costs of mating, we held females at a low or high density with males whose claspers were modified to prevent insemination and compared these to females held with normal males and to those held with females or alone. A reduced longevity was observed when females were held under high-density conditions with males or females, regardless if male claspers had been modified. There was no consistent effect of harassment on female fecundity. Net reproductive rate (R 0) was higher in females held at low density with normal males compared to females held with males in the other treatments, even though only a small number of females showed direct evidence of remating. Indirect costs and benefits that were not due to harassment alone were observed. Daughters of females held with normal males at high density had reduced longevity compared to daughters from females held without conspecifics. However, their fitness (R 0) was higher compared to females in all other treatments. Overall, our results indicate that A. aegypti females do not suffer a fitness cost from harassment of males when kept at moderate densities, and they suggest the potential for benefits obtained from ejaculate components.  相似文献   
549.
Biodiversity and human well-being strategies are only as good as the set of ideas people think about. We evaluated value-focused thinking (VFT), a framework that emphasizes creating objectives and strategies that are responsive to the objectives. We performed a proof-of-concept study of VFT with 6 conservation planning teams at a global conservation organization. We developed a package of materials related to VFT, including meeting–session agendas, a virtual facilitation template, facilitator's guide, and evaluation questionnaires. We used these materials to test whether VFT applied in a group setting resulted in high-quality conservation strategies and participant satisfaction and whether our materials were scalable, meaning that someone newly trained in VFT could facilitate planning meetings that resulted in high-quality strategies and participant satisfaction, as compared with an experienced VFT facilitator. Net response indicated positive compelling, feasible, creative, and representative ratings for the conservation strategies per team. Participants indicated satisfaction overall, although satisfaction was greater for objectives than for strategies. Among the participants with previous conservation planning experience, all were at least as satisfied with their VFT strategies compared with previously developed strategies, and none were less satisfied (p = 0.001). Changes in participant satisfaction were not related to facilitator type (experienced or inexperienced with VFT) (p > 0.10). Some participants had a preconceived sense of shared understanding of important values and interests before participating in the study, which VFT strengthened. Our results highlight the advantages of structuring the development and evaluation of conservation planning frameworks around VFT.  相似文献   
550.
降低二噁英(PCDD/Fs)的检出限(LOD)可以更好地估计这类有毒化合物在食品中的含量.通常的分析方法用无分流进样注入内径0.25 mm长60m的色谱柱.  相似文献   
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