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Acid rain in Asia 总被引:3,自引:0,他引:3
Acid rain has been an issue of great concern in North America and Europe during the past several decades. However, due to the passage of a number of recent regulations, most notably the Clean Air Act in the United States in 1990, there is an emerging perception that the problem in these Western nations is nearing solution. The situation in the developing world, particularly in Asia, is much bleaker. Given the policies of many Asian nations to achieve levels of development comparable with the industrialized world—which necessitate a significant expansion of energy consumption (most derived from indigenous coal reserves)—the potential for the formation of, and damage from, acid deposition in these developing countries is very high. This article delineates and assesses the emissions patterns, meteorology, physical geology, and biological and cultural resources present in various Asian nations. Based on this analysis and the risk factors to acidification, it is concluded that a number of areas in Asia are currently vulnerable to acid rain. These regions include Japan, North and South Korea, southern China, and the mountainous portions of Southeast Asia and southwestern India. Furthermore, with accelerated development (and its attendant increase in energy use and production of emissions of acid deposition precursors) in many nations of Asia, it is likely that other regions will also be affected by acidification in the near future. Based on the results of this overview, it is clear that acid deposition has significant potential to impact the Asian region. However, empirical evidence is urgently needed to confirm this and to provide early warning of increases in the magnitude and spread of acid deposition and its effects throughout this part of the world. 相似文献
414.
Packaging waste has become a focus for attention by policy‐makers in a number of countries. This article offers a simple policy measure — a packaging tax or levy — which serves the required aims of policy, namely: reducing waste at source; increasing the rate of recycling; and consistency with the polluter pays principle. The tax is illustrated in the context of beverage containers in the UK and Japan. The merits of the proposal are its simplicity and flexibility. The article suggests that the relevant environmental damages are captured by waste disposal costs and litter. Other life cycle impacts, such as emissions from energy use, could be included but only if there are not more efficient ways of regulating them. 相似文献
415.
David L. Berger 《Journal of the American Water Resources Association》1992,28(5):959-965
ABSTRACT: Most water-resouree investigations in semiarid basins of the Great Basin in western North America conclude that ground-water recharge from direct precipitation on the valley floor is negligible. However, many of these basins contain large areas covered by unvegetated, active sand dunes that may act as conduits for ground-water recharge. The potential for this previously undocumented recharge was investigated in an area covered by sand dunes in Desert Valley, northwestern Nevada, using a deep percolation model. The model uses daily measurements of precipitation and temperature th determine energy and moisture balances, from which estimates of long-term mean annual recharge are made. For the study area, the model calculated a mean annual recharge rate of as much as 1.3 inches per year, or 17 percent of the long-term mean precipitation. Model simulations also indicate that recharge would be virtually zero if the study area were covered by vegetation rather than dunes. 相似文献
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This study investigated the possible role of self-efficacy in the stress process by examining relations between stressors (role ambiguity, situational constraints, and hours), strains (job dissatisfaction, anxiety, frustration, and turnover intent), and efficacy beliefs (both individual and collective). Individual efficacy was related to only two of the four strains and had no mediating or moderating effects. Collective efficacy, however, was strongly related to both stressors and strains. Collective efficacy also moderated the effect of work hours and mediated the relation between situational constraints and two of the strain measures. It was concluded that the theory of individual self-efficacy (Bandura, 1977) may not adequately explain collective efficacy. Future research on the self-efficacy construct as well as its role in the stress process was suggested. 相似文献
418.
This study explored whether two principles describe the relationship between the size of a pay increase (a bonus expressed as a percentage of current salary) and the attractiveness of that increase. Based on a sample of sales personnel (N = 639) and consistent with the constant proportion principle of the psychophysical law, pay increase attractiveness was unrelated to current salary level after controlling for the size of the percentage increase. In addition, at any given salary level, the relationship between the size of the increase and its attractiveness was curvilinear. The attractiveness of larger and larger bonus percentages continues to increase, but at a decreasing rate supporting the principle of diminishing returns. 相似文献
419.
David Pimentel 《Journal of Agricultural and Environmental Ethics》1993,6(1):53-60
The use of organic farming technologies has certain advantages in some situations and for certain crops such as maize; however, with other crops such as vegetables and fruits, yields under organic production may be substantially reduced compared with conventional production. In most cases, the use of organic technologies requires higher labor inputs than conventional technologies. Some major advantages of organic production are the conservation of soil and water resources and the effective recycling of livestock wastes when they are available. 相似文献
420.
David M. Wolock Gregory J. McCabe Gary D. Tasker Marshall E. Moss 《Journal of the American Water Resources Association》1993,29(3):475-486
ABSTRACT: The effects of potential climate change on water resources in the Delaware River basin were determined. The study focused on two important water-resource components in the basin: (1) storage in the reservoirs that supply New York City, and (2) the position of the salt front in the Delaware River estuary. Current reservoir operating procedures provide for releases from the New York City reservoirs to maintain the position of the salt front in the estuary downstream from freshwater intakes and ground-water recharge zones in the Philadelphia metropolitan area. A hydrologic model of the basin was developed to simulate changes in New York City reservoir storage and the position of the salt front in the Delaware River estuary given changes in temperature and precipitation. Results of simulations indicated that storage depletion in the New York City reservoirs is a more likely effect of changes in temperature and precipitation than is the upstream movement of the salt front in the Delaware River estuary. In contrast, the results indicated that a rise in sea level would have a greater effect on movement of the salt front than on storage in the New York City reservoirs. The model simulations also projected that, by decreasing current mandated reservoir releases, a balance can be reached wherein the negative effects of climate change on storage in the New York City reservoirs and the position of the salt front in the Delaware River estuary are minimized. Finally, the results indicated that natural variability in climate is of such magnitude that its effects on water resources could overwhelm the effects of long-term trends in precipitation and temperature. 相似文献