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71.
72.
Despite continuous investment and various efforts to control pollution, urban water environments are worsening in large parts of the developing world. In order to reveal potential constraints and limitations of current practices of urban water management and to stimulate proactive intervention, we conducted a material flow analysis of the urban water system in Kunming City. The results demonstrate that the current efficiency of wastewater treatment is only around 25% and the emission of total phosphorous from the city into its receiving water, Dianchi Lake, is more than 25 times higher than its estimated tolerance. With regard to the crisis of water quantity and quality, the goal of a sustainable urban water environment cannot be attained with the current problem-solving approach in the region due to the technical limitations of the conventional urban drainage and treatment systems. A set of strategies is therefore proposed. The urban drainage system in Zurich is used as a reference for a potential best-available technology for conventional urban water management (BAT) scenario in terms of its low combined frequency of sewer overflow.  相似文献   
73.
This paper develops and tests hypotheses concerning some psychological correlates of role ambiguity and role conflict in a population that has not been extensively studied in relation to stress, union stewards. Survey data on role ambiguity and role conflict, the indicators of stress, were collected from 285 stewards at the local union steward meeting, with the stewards perceiving a moderate amount of role ambiguity and perceiving a lesser amount of role conflict. The stewards were also asked about their role expectations, their motivations for remaining a steward, their grievance handling strategies, and their affective commitment toward the union and employer. Each of those four sets of variables was hypothesized to be related to role ambiguity and role conflict and each was influential in explaining variance. As predicted, those stewards who were more motivated to remain stewards for personal reasons had both higher role ambiguity and higher role conflict. Further, the conditions of being more motivated to remain a steward to help the union and employees and having higher union commitment were associated with lower role conflict, but, opposite to the hypotheses, higher role ambiguity.  相似文献   
74.
ABSTRACT: The Floridan Aquifer is the primary source of water in the coastal area of Santa Rosa County, Florida. In order to optimize well field design and analyze aquifer stress problems, the USGS MODFLOW code (McDonald and Harbaugh, 1988) is applied to develop a numerical computer model of the aquifer. The Geographical Information System (GIS) is the primary tool used in the development of the model grid, performance of the modeling procedure, and model analysis. The GIS is used in generating multiple grids in which to simulate both regional scale and local scale flow. The grid topology is recorded in geographic coordinates which facilitates geo-referencing and orientation of the grid to base maps and data coyerages. The GIS allows data transfer from various coverages to the nodes of the block centered grid where hydrogeologic information is stored as attributes to the grid coverage. From this grid coverage, pertinent information is queried within the GIS environment and used to generate the input files for the MODFLOW simulation. After MODFLOW execution, simulated heads and drawdown are imported into the grid coverage where residual error and recharge rates can be calculated. Contoured surfaces are then created for selected data sets including simulated heads, drawdown, residual error, and recharge rates. Model calibration is conducted utilizing the GIS to generate and process data sets associated with model simulations.  相似文献   
75.
Investigations using chlorophyll fluorescence induction kinetics provide the parameters Rfd, L, and Ap to characterize different specifications of the photosynthetic system (PS). The application of ozone, with concentrations between 100 microg m(-3) and 2000 microg m(-3) to spruce in closed chambers yields a reduction of Rfd between 6% and 23% for the current year's needles, which indicates a reduced potential photosynthetic capacity. Further measurements on the current year's needles of spruce of the damage classes S0/S1, S2 and S3 show also a reduction of Rfd of between 7% and 14% in 2 successive years. In addition, the parameter L increases for damaged trees by between 11% and 49%, indicating a change of the chlorophyll content and of the internal energy distribution between PSI and PSII. As no effect of L can be observed with ozone fumigation, it is concluded that the change of some specifications of the PS can be simulated well by ozone fumigation (e.g. Rfd) while other specifications cannot (e.g. L).  相似文献   
76.
Animal welfare is an importantsocietal issue in Switzerland. Policy makershave responded with a strict legislation onanimal protection and with two programs topromote animal friendly husbandry. Alsoprivate actors in the meat industry initiatedprograms for animal friendly meat productionto meet consumers' expectations. Labeled meathas a market share of over 20%. Depending onthe stakeholders responsible for the labels,their objectives vary. While retailers want toattract consumers with meat produced in ananimal friendly and environmentally compatiblemanner and with products of consistently goodsensory quality, producers want to keep marketshares and increase their revenues.  相似文献   
77.
Carlisle in northwest England suffered its worse floods for more than 180 years in 2005. A study, reported here, was undertaken to assess the health and social impacts of these floods via in‐depth, taped individual and focus‐group interviews with people whose homes had been flooded and with agency workers who helped them. Respondents spoke of physical health ailments, psychological stress, water health‐and‐safety issues related to the floods, and disputes with insurance and construction companies, which they felt had caused and exacerbated psychological health problems. Support workers also suffered from psychological stress. Furthermore, it was found that people had low expectations of a flood and were not prepared. The findings are presented in five sections covering flood risk awareness, water contamination issues, physical health, mental health, and impact on frontline support workers. The discussion focuses on the implications of the findings for policy and practice vis‐à‐vis psychological health provision, contamination issues, training and support for frontline support workers, matters relating to restoration, and preparation for flooding.  相似文献   
78.
Evaluations of water footprint (WF) used to enhance performance of policies on water utilization will benefit from combining WF analysis with methods from sustainability analysis. For this purpose, this paper analyzes the WF of China’s five main food crops, which together account for roughly 33 % of the nation’s water consumption. We assess distributional equity at the provincial scale and use the IPAT identity and a decoupling analysis to assess the scale of both national and provincial WF consumption, the factors influencing the WF fluctuation, and the efficiency of water allocation. Results show that although it is difficult in the short term to end the unsustainable WFs of China’s five main food crops, more efficient allocation can be achieved through appropriate agricultural policy modification. In the long term, distributional equity at the provincial level must be the key factor in achieving sustainable agriculture in China.  相似文献   
79.
The amount of information required to adapt to climate change is vast: downscaled climate projections, information on environmental impact, sectoral performance, external drivers, regional strategies, policies and practices. It can be argued that most of this information is accessible at the community/regional level, and thus, the important challenges to adaptation are not information gaps, but constraints created by fragmented planning decisions and a sector-by-sector basis for financial and human resource allocations. To strategically address this through adaptation planning, we developed and tested a place-based decision-making framework that creates an integrated platform for considering regional and global sectoral drivers in Eastern Ontario, Canada. Using available socioeconomic and biophysical information from regional authorities, alternative future scenarios were used to describe the range of socioeconomic futures and their vulnerabilities to climate change. We found that: (1) integration of diverse sets of available data (rather than narrowly focused sectoral assessments) helped identify shared common objectives (maximizing the long-term environmental, economic, social well-being within the region), (2) a high degree of congruence existed as the key drivers of change, irrespective of sector, (3) exploring the future scenarios highlighted shared regional priorities and helped identify adaptation priorities requiring more integrated regional planning.  相似文献   
80.
This paper draws on climate justice principles developed in the context of international negotiations between national governments to assess the distribution of carbon reduction roles between different actors involved in residential energy use within the UK. In so doing, it aims to provide a new understanding of equity aspects of current residential policy and to highlight opportunities for more effective and equitable policy. The paper uses three criteria: rights and corresponding duties; mitigation responsibilities and capabilities. It applies them systematically to assess the roles of five key actors involved in residential energy use in the UK. The assessment finds a suboptimal distribution of actors’ duties, responsibilities and capabilities and roles and discusses whether and how a more effective and fair allocation of outcomes, in terms of carbon reduction and fuel poverty, could be achieved. In particular, it raises questions about whether the right actors are being legally obliged or incentivised to deliver energy efficiency improvements, and suggests that particular actors – local authorities and community groups – are under-used and require greater government support with capability. The paper represents the first use of international climate justice frameworks to investigate residential energy policy within a country.  相似文献   
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