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991.
Russian Journal of Ecology - For the first time, the density of fish population has been quantitatively assessed in the Mekong River delta in the territory of the Socialist Republic of Vietnam. The...  相似文献   
992.
Many jurisdictions around the globe have well-developed regulatory frameworks for the derivation and implementation of water quality guidelines (WQGs) or their equivalent (e.g. environmental quality standards, criteria, objectives or limits). However, a great many more still do not have such frameworks and are looking to introduce practical methods to manage chemical exposures in aquatic ecosystems. There is a potential opportunity for learning and sharing of data and information between experts from different jurisdictions in order to deliver efficient and effective methods to manage potential aquatic risks, including the considerable reduction in the need for aquatic toxicity testing and the rapid identification of common challenges. This paper reports the outputs of an international workshop with representatives from 14 countries held in Hong Kong in December 2011. The aim of the workshop and this paper was to identify ‘good practice’ in the development of WQGs to deliver to a range of environmental management goals. However, it is important to broaden this consideration to cover often overlooked facets of implementable WQGs, such as demonstrable field validation (i.e. does the WQG protect what it is supposed to?), fit for purpose of monitoring frameworks (often an on-going cost) and finally how are these monitoring data used to support management decisions in a manner that is transparent and understandable to stakeholders. It is clear that regulators and the regulated community have numerous pressures and constraints on their resources. Therefore, the final section of this paper addresses potential areas of collaboration and harmonisation. Such approaches could deliver a consistent foundation from which to assess potential chemical aquatic risks, including, for example, the adoption of bioavailability-based approaches for metals, whilst reducing administrative and technical burdens in jurisdictions.  相似文献   
993.
Climate change and urbanization are among the most significant trends of the twenty-first century, affecting global natural resources such as water, economic development and human well-being. The growth of the world population will be absorbed by the cities. The necessity of cities adapting to these trends calls for radical changes in urban water management. In this paper, baseline assessments, i.e., City Blueprints, have been carried out for 45 municipalities and regions in 27 countries, mainly in Europe. The assessments showed that cities vary considerably with regard to their water management. This is also captured in the Blue City Index® (BCI), the arithmetic mean of 24 indicators comprising the City Blueprint®. Theoretically, the BCI has a minimum score of 0 and a maximum score of 10. The actual BCIs in the 45 cities and regions varied from 3.5 (Kilamba Kiaxi in Angola) to 8.5 (Helsingborg in Sweden). The BCI was positively and significantly correlated with the gross domestic product per person, the ambitions of the local authorities regarding water management, the voluntary participation index and governance indicators according to the World Bank (2013). The study also demonstrated a very significant correlation between the BCI and the University of Notre Dame Global Adaptation Index. The impacts of water scarcity and floods in cities are discussed. It is concluded that cities in transitional and developing countries are particularly at risk.  相似文献   
994.
Environmental Management - In order to foster the potential of exclosures to sequester carbon, it is understood that they are increasingly assisted through enrichment planting. To study the impact...  相似文献   
995.
Although international trade in energy may offer a flexible and cost effective means by which European countries could meet their renewable energy targets, developers in the exporting nation can face local opposition for reasons which are not always clear. Using focus groups and a public survey, we contrast perspectives between local stakeholders and wind farm operators and investigate the community impacts associated with large-scale wind energy for domestic use and export from Ireland to the UK. Although the export of renewable energy from Ireland to the UK is currently on hold, our findings suggest that significant investment is required by the state and wind farm operators in better information provision, trust building, effective instruments to internalise wind farm externalities and co-management arrangements before Ireland can fully capture the benefits of wind exports to the UK.  相似文献   
996.
Community gardens vary in several ways: they are cultivated by different kinds of communities in various locations, entail individual or communal plots and the extent of active participation (e.g. gardening) differs. In this paper, we study seven community gardens with varying organisational designs and objectives, and investigate the extent to which these influence the enhancement of social cohesion. We also take into account to what extent differences in motivation among community gardeners matter. Despite these differences in motivation, however, we find that in all of the cases studied, people talk to and get to know others, and mutual help is widespread. We, therefore, conclude that community gardens contribute to the development of social cohesion – even if people are not particularly driven by social motivations. Moreover, while participants who are motivated by the social aspects of gardening naturally show a higher level of appreciation for them, these social aspects also bring added value for those participants who are motivated primarily by growing vegetables.  相似文献   
997.
Lynn White Jr.’s “The Historical Roots of Our Ecologic Crisis,” which was published in Science in 1967, has played a critical role in precipitating interdisciplinary environmental studies. Although White advances a multifaceted argument, most respondents focus on his claim that the Judeo‐Christian tradition, especially Christianity, has promoted anthropocentric attitudes and environmentally destructive behaviors. Decades later, some scholars argue contrarily that Christianity in particular and the world's predominant religions in general are becoming more environmentally friendly, known as the greening‐of‐religion hypothesis. To test these claims, we conducted a comprehensive review of over 700 articles—historical, qualitative, and quantitative—that are pertinent to them. Although definitive conclusions are difficult, we identified many themes and dynamics that hinder environmental understanding and mobilization, including conservative theological orientations and beliefs about the role of divine agency in preventing or promoting natural events, whether the religion is an Abrahamic tradition or originated in Asia. On balance, we found the thrust of White's thesis is supported, whereas the greening‐of‐religion hypothesis is not. We also found that indigenous traditions often foster proenvironmental perceptions. This finding suggests that indigenous traditions may be more likely to be proenvironmental than other religious systems and that some nature‐based cosmologies and value systems function similarly. Although we conclude White's thesis and subsequent claims are largely born out, additional research is needed to better understand under what circumstances and communication strategies religious or other individuals and groups may be more effectively mobilized to respond to contemporary environmental challenges.  相似文献   
998.
This study evaluated the feasibility of supplementing groundwater monitoring protocols by assessing the vadose zone for the extent of residual subsurface contamination. The study also characterized the response of the soil gas signatures with respect to different soil types and degrees of contamination. A field study was conducted at a former gasoline vending station located in Ottawa, Canada. The current state of contamination was determined by analysis of soil samples taken from boreholes. A series of 10 nested soil gas wells with monitoring depths of 0.75, 1.5, 2.25 and 3.0 m were then installed. Using these wells, soil gas surveys were performed at regular intervals over an extended period to quantify Gaseous TPH (TPH g ), oxygen and carbon dioxide concentrations in the soil gas. Results indicate that soil gas wells located near the source term exhibited characteristic soil gas signatures and significant fluctuations in TPH g , oxygen, and carbon dioxide concentrations with time. Soil gas wells located beyond the soil contamination demonstrated limited correlation between TPH g , oxygen and carbon dioxide concentrations and decreased seasonal variability.  相似文献   
999.
Cadmium (Cd) is known as one of the most dangerous environmental and industrial pollutants. It has no biological function and accumulates mainly in metabolically active tissue even at low concentrations, which in turn may cause tissue damage. The effect of Cd on the endocrine systems of fish is not well known. To test the hypothesis that Cd is a chemical stressor, Oreochromis sp. were exposed to waterborne cadmium chloride and their endocrine stress response (plasma cortisol) was investigated after 4 days and 20 days. The plasma cortisol levels were analyzed using reverse-phase high performance liquid chromatography with UV detection (λ = 250 nm) after liquid–liquid extraction. The detection limit of the method was found to be 0.87 ng/mL plasma. This study provides evidence that Cd probably causes exhaustion of endocrine systems. Oreochromis sp. exposure to Cd resulted in a 15%–53% and 52%–91% suppression of cortisol release after 4 days and 20 days of exposure, respectively, in comparison with the control group. The results suggest that Cd still activates the endocrine system at 20 days and the interrenal cells of Oreochromis sp. were not impaired after 20 days of exposure to Cd.  相似文献   
1000.
While adaptation has received a fair amount of attention in the climate change debate, barriers to adaptation are the focus of a more specific, recent discussion. In this discussion, such barriers are generally treated as having a uniform, negative impact on all actors. However, we argue that the precise nature and impact of such barriers on different actors has so far been largely overlooked. Our study of two drought-prone communities in rural Ethiopia sets out to examine how female- and male-headed households adapt to climate change, particularly focusing on how a variety of barriers influence the choice of adaptation measures to varying extents. To this purpose, we built a conceptual framework based on the Sustainable Livelihood Approach. Data were collected using semi-structured interviews and focus group discussions with male- and female-headed households, community leaders and local extension workers. Our findings suggest that gender-based differences in the choice of adaptation measures at the household level are driven by cultural, social, financial and institutional barriers. Barriers to adaptation—particularly when interacting—have a differentiated impact upon different actors. This outcome hints at the need for donors and policymakers to develop intervention strategies that are sensitive to this fact.  相似文献   
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