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821.
ABSTRACT: Most hydrologic models require input parameters which represent the variability found across an entire landscape. The estimation of such parameters is very difficult, particularly on rangeland. Improved model parameter estimation procedures are needed which incorporate the small-scale and temporal variability found on rangeland. This study investigates the use of a surface soil classification scheme to partition the spatial variability in hydrologic and interrill erosion processes in a sagebrush plant community. Four distinct microsites were found to exist within the sagebrush coppice-dune dune-interspace complex. The microsites explained the majority of variation in hydrologic and interrill erosion response found on the site and were discernable based on readily available soil and vegetation information. The variability within each microsite was quite low and was not well correlated with soil and vegetation properties. The surface soil classification scheme defined in this study can be quite useful for defining sampling procedures, for understanding hydrologic and erosion processes, and for parameterizing hydrologic models for use on sagebrush range-land.  相似文献   
822.
We develop an understanding of local governmental efforts to address earthquake risks. Our data for a sample of California and Washington cities' risk-reduction efforts sort into two different clusters of leading jurisdictions as contrasted with a cluster of lagging jurisdictions. We explain differences among the three categories of cities in terms of different political-economic factors. Local governmental willingness and ability to undertake risk-reduction programs have more to do with local political demands and community resources than with objective risk or previous earthquake experience. State mandates have a selective impact on local risk-reduction efforts. The principal policy lessons concern the need to address gaps in local risk-reduction efforts through more careful targeting of federal and state earthquake programs and by including stronger teeth within state mandates.  相似文献   
823.
The classical model of a paradigm shift is used to explore changes that are occurring in public lands and water resources management. Recent policy developments suggest that the traditional paradigm, which is characterized by sustained yield, is in the process of being invalidated. While no new paradigm has been fully accepted, the emerging paradigm does appear to be based on two principles: ecosystem management and collaborative decision making. Implementation of these two principles is likely to require extensive revision of traditional management practices and institutions. Failure to address these issues could result in adoption of the rhetoric of change without any lasting shift in management practices or professional attitudes.  相似文献   
824.
The United Kingdom's 1986 Agriculture Act provided the basis for the designation of Environmentally Sensitive Areas (ESAs) “in order to contribute towards the introduction or the maintenance of farming practices compatible with the requirements of the protection of the environment”. This paper examines the establishment of ESAs in Scotland, setting their creation and operation against the background of the move away from productionist farm support policies. There is consideration of how agriculture and the environment have fared since the first Scottish ESAs were created in 1987, with special reference to the Breadalbane ESA.  相似文献   
825.
This paper considers the external costs of public access on privately‐owned farm and estate land in Scotland. The increased costs and reductions in income associated with public access are found to be highly variable and site‐specific, with the main effects on land in areas of high population density or high scenic quality, or with recreational attributes. Although costs were on average higher for estates, reflecting their larger area and recreational potential, on a per‐hectare basis the costs of access were greater for the farm sector. Whilst much of the public access exists through de facto rights on open‐access land, there was evidence for an increasing commercialization of open‐air recreation, particularly with respect to more specialized activities. The discussion considers the extent to which the costs of access for land managers are reflected in policies determining the public provision of countryside access.  相似文献   
826.
Benchmarking is a process companies use to identify and evaluate the best practices, both inside and outside their industry, in their field of interest. The goal is to identify gaps between their performance and the benchmarks so that they can find ways to improve their performance. This article describes an early benchmarking effort in the environmental management area of the Weyerhaeuser Company.  相似文献   
827.
While some companies have established scoring systems within their audit programs, few utilize the full potential for measurement of the information gathered and subsequently produced from audits. In this article, the use of a computerized tracking system developed and used by Browning-Ferris Industries is discussed, along with a data report that details the completion of audit items and helps assure that action plans resulting from environmental audits are completed. This and other summary reports from the computer tracking system have provided meaningful measures of individual facilities' and overall company performance.  相似文献   
828.
This paper describes a novel technology for the removal of solidified radioactive waste from underground storage tanks at the DOE Hanford site in southeast Washington. The process involves the use of a unique high pressure system which pulverizes the hardened saltcake with stainless steel pellets to a powder for easy vacuum removal. The steel pellets can be magnetically separated from the waste material for re-use. Specifically this study analyzes the effects of various steel abrasives, pressure of the air stream, and stand-off distance on removal rates and penetration depth on simulated saltcake samples using the high pressure technique. A full-scale test set-up and protocol were implemented to allow for comprehensive testing. To insure reproducibility of the method, tests were then run for the optimum removal parameters. A time-dependent test was also conducted to determine the relationship of removal rates to length of pressure blasts. The results of these tests revealed that stand-off distance and pressure could be positively correlated to removal volumes. Additionally, a statistical analysis confirmed that nozzle angle is independent of removal rate. This study demonstrated that the pellet ‘blaster’ technique is a safe, effective method for removal of radioactive wastes without any increase in either waste mass or volume.  相似文献   
829.
Corporations own approximately 25% of all private land in the United States and, therefore, play an essential role in protecting biodiversity and maintaining natural habitats. The Wildlife Habitat Council (WHC) is a unique joint venture between conservation organizations and corporations to utilize corporate lands for ensuring biodiversity. The following case studies demonstrate how corporations have helped ensure healthy ecosystems and provided critical leadership in regional efforts. Amoco Chemical Company's Cooper River Plant has been instrumental in developing a cooperative project that involves numerous corporations, plantation owners, private citizens, nonprofit organizations, government agencies, and community groups to develop a comprehensive, ecosystem-based management plan for part of the Cooper River in Charleston, South Carolina, USA. The second case focuses on the Morie Company, a national sand quarry operator headquartered in southern New Jersey, USA. Morie Company is working with WHC, community groups, the Pinelands Commission, and other state regulatory agencies to explore sustainable development opportunities for companies within the Pinelands regulations. The third case takes us to DuPont Company's Asturias, Spain, site. A win—win success story of improved habitat and cost savings is the result of DuPont's concern for the environment, ability to work with a variety of groups, and willingness to consider innovative restoration techniques. The fourth case discusses Consumers Power Company's Campbell Plant in West Olive, Michigan, USA. In addition to implementing projects that contribute to biodiversity, Consumers Power has developed an environmental education field station to teach others about the importance of natural habitats. The final case highlights Baltimore Gas & Electric Company's efforts to maintain habitat for endangered species at their Calvert Cliffs site in Maryland.  相似文献   
830.
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