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261.
ABSTRACT: Regression and time-series techniques have been used to synthesize and predict the stream flow at the Foresta Bridge gage from information at the upstream Pohono Bridge gage on the Merced River near Yosemite National Park. Using the available data from two time periods (calendar year 1979 and water year 1986), we evaluated the two techniques in their ability to model the variation in the observed flows and in their ability to predict stream flow at the Foresta Bridge gage for the 1979 time period with data from the 1986 time period. Both techniques produced reasonably good estimates and forecasts of the flow at the downstream gage. However, the regression model was found to have a significant amount of autocorrelation in the residuals, which the time-series model was able to eliminate. The time-series technique presented can be of great assistance in arriving at reasonable estimates of flow in data sets that have large missing portions of data.  相似文献   
262.
ABSTRACT: “Nuclear winter,” more properly called “nuclear fall,” could be caused by injection of large amounts of dust into the atmosphere. Besides causing a decrease in temperature, it could be accompanied by “nuclear drought,” a catastrophic decrease in precipitation. Dry land agriculture would then be impossible, and municipal, industrial, and irrigation water supplies would be diminished. It has been argued that nuclear winter/fall poses a much greater threat to human survival than do fall out or the direct impacts of a conflict. However, this does not appear to be true, at least for the U.S. Even under the unprecedented drought that could result from nuclear fall, water supplies would be available for many essential activities. For the most part, ground water supplies would be relatively invulnerable to nuclear drought, and adequate surface supplies would be available for potable uses. This assumes that conveyance facilities and power supplies survive a conflict largely intact or can be repaired.  相似文献   
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Policies such as the US Healthy Forests Restoration Act (HFRA) mandate collaboration in planning to create benefits such as social learning and shared understanding among partners. However, some question the ability of top-down policy to foster successful local collaboration. Through in-depth interviews and document analysis, this paper investigates social learning and transformative learning in three case studies of Community Wildfire Protection Planning (CWPP), a policy-mandated collaboration under HFRA. Not all CWPP groups engaged in social learning. Those that did learned most about organisational priorities and values through communicative learning. Few participants gained new skills or knowledge through instrumental learning. CWPP groups had to commit to learning, but the design of the collaborative-mandate influenced the type of learning that was most likely to occur. This research suggests a potential role for top-down policy in setting the structural context for learning at the local level, but also confirms the importance of collaborative context and process in fostering social learning.  相似文献   
266.
The Pressure-State-Response framework for environmental reporting was used as a basis to develop a long-term study of people's perceptions of the state of the New Zealand environment. A postal survey of 2000 people, randomly drawn from the New Zealand electoral roll was used to gather data--an effective response rate of 48% was achieved. A range of different resource sectors was examined. We report on New Zealand's air, native animals and plants, and marine fisheries, as well as New Zealand compared to other developed countries. Respondents generally considered that in terms of pressures, states and responses, New Zealand was performing better than other developed countries and that for the resources examined here overall performance was in the adequate to good range, except for marine fisheries. The survey appears to be a useful tool for linking perceptions data into State of the Environment reporting. It also helps identify policy issues where perceptions do not match other scientific evidence or management initiatives. Such findings can be important for the successful implementation of policy measures.  相似文献   
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Editorial     

Editorial Commentary

Editorial  相似文献   
268.
Setback regulations-legislated distances that livestock production facilities must be removed from surrounding properties-are meant to mitigate odor impacts. If the setback length is too short, then there is evidence that surrounding properties and people suffer uncompensated damages. If, on the other hand, setback lengths are too long, then livestock producers may be paying more than that required to compensate for odor-related environmental damages. The purpose of this study is to assess the impact of Kentucky's livestock production facility setbacks on the value of surrounding properties and farm financial management decisions. This paper develops a model of the benefits of livestock odor reduction and the livestock odor abatement cost associated with setback lengths paid by producers. The results of this investigation indicate that the mandated setback lengths for Kentucky are too short. Livestock production firms are worse off under longer setback lengths, but the losses to surrounding home owners far exceed the firm gains at the mandated setbacks. A finding of this study is that the firm has no incentive to completely protect the legislated setback length. Livestock producers in compliance with the relevant setback length may feel protected from odor lawsuits despite damage being done to surrounding property. This suggests that the perceived threat of lawsuit is currently low in the state of Kentucky. Both industry and public goals could be met from further research including location and economic impact of livestock production.  相似文献   
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A ‘seamless web’ framework of environmental regulation is emerging. The seamless web provides a comprehensive and holistic framework for facilitating the transition to ecologically sustainable development (ESD). This seamless web comprises numerous threads, that is regulators and regulatory mechanisms, which provide the framework in which society may attain effective protection from environmental degradation. Regulatory bodies include government and state regulators, NGOs, industry peers, investors and consumers. Regulatory mechanisms and incentives range through lower costs, increased market share and long term resource access and sanctions ranging through incarceration of directors, license withdrawal, fines, falling profits, loss of market share and falling investor confidence. We conclude that self‐regulation is a useful mechanism to promote environmental protection, and that industry will increasingly face pressure to improve its environmental performance from many stakeholders. The seamless web framework recognizes the pivotal role of industry in environmental regulation, catering for a range of corporate cultures, and thereby stimulating innovation of appropriate technology. Copyright © 1999 John Wiley & Sons, Ltd and ERP Environment.  相似文献   
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