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401.
ABSTRACT. This work evaluates the economic losses due to diversion from the Snake River during the relatively low-flow year May 1928-April 1929. The results determine the losses due to pollution abatement and power generation for several different patterns and volumes of diversion, and the tool of analysis is dynamic programming. 相似文献
402.
Perceptions of Species Abundance,Distribution, and Diversity: Lessons from Four Decades of Sampling on a Government-Managed Reserve 总被引:2,自引:0,他引:2
J. Whitfield Gibbons
Author to whom correspondence should be addressed. Vincent J. Burke Jeffrey E. Lovich Raymond D. Semlitsch Tracey D. Tuberville J. Russell Bodie Judith L. Greene Peter H. Niewiarowski Howard H. Whiteman David E. Scott Joseph H. K. Pechmann Christopher R. Harrison Stephen H. Bennett John D. Krenz Mark S. Mills Kurt A. Buhlmann John R. Lee Richard A. Seigel Anton D. Tucker Tony M. Mills Trip Lamb Michael E. Dorcas Justin D. Congdon Michael H. Smith David H. Nelson M. Barbara Dietsch Hugh G. Hanlin Jeannine A. Ott Deno J. Karapatakis 《Environmental management》1997,21(2):259-268
/ We examined data relative to species abundance, distribution, anddiversity patterns of reptiles and amphibians to determine how perceptionschange over time and with level of sampling effort. Location data werecompiled on more than one million individual captures or observations of 98species during a 44-year study period on the US Department of Energy's(DOE) Savannah River Site National Environmental Research Park (SRS-NERP) inSouth Carolina. We suggest that perceptions of herpetofaunal speciesdiversity are strongly dependent on level of effort and that land managementdecisions based on short-term data bases for some faunal groups could resultin serious errors in environmental management. We provide evidence thatacquiring information on biodiversity distribution patterns is compatiblewith multiyear spatially extensive research programs and also provide aperspective of what might be achieved if long-term, coordinated researchefforts were instituted nationwide.To conduct biotic surveys on government-managed lands, we recommend revisionsin the methods used by government agencies to acquire and report biodiversitydata. We suggest that government and industry employees engaged inbiodiversity survey efforts develop proficiency in field identification forone or more major taxonomic groups and be encouraged to measure the status ofpopulations quantitatively with consistent and reliable methodologies. Wealso suggest that widespread academic cooperation in the dissemination ofinformation on regional patterns of biodiversity could result byestablishment of a peer-reviewed, scientifically rigorous journal concernedwith status and trends of the biota of the United States. KEY WORDS: Abundance; Amphibian; Biodiversity; Distribution; Landmanagement; Reptile 相似文献
403.
Today, environmental managers are learning new ways of adding value to their organizations. Before, the environmental department was an overhead expense—an indirect support group required for complying with burdensome regulations. Now, such departments add insights and value during strategic planning sessions, identify efficiency improvement opportunities, provide a superior return on investment, and—bottom line—improve profits. The primary approach to meeting the challenge is a new environmental management system (EMS) that identifies, measures, and manages a diverse set of internal and external customer needs. These needs include environmental cleanups, regulatory compliance, pollution prevention, and design for the environment—and each represents a potential improvement opportunity. Unfortunately, most organizations have so many such needs that all cannot be addressed at once, given the resource constraints of a competitive business climate. Thus, priority is a key concept of an effective EMS. This article describes an innovative application of consensus-building tools that quickly identify and set priorities for diverse environmental programs. The article also shows how appropriate performance measures will align these programs with corporate goals and objectives. 相似文献
404.
Risk decision-making in natural hazards encompasses a plethora of environmental, socio-economic and management-related factors, and benefits greatly from exploring possible patterns and relations among these multivariate factors. Artificial neural networks, capable of general pattern classifications, are potentially well suited for risk decision support in natural hazards. This paper reports an example that assesses the risk patterns or probabilities of house survival from bushfires using artificial neural networks, with a simulation data set based on the empirical study by Wilson and Ferguson (Predicting the probability of house survival during bushfires, Journal of Environmental Management 23 (1986) 259–270). The aim of this study was to re-model and predict the relationship between risk patterns of house survival and a series of independent variables. Various configurations for input and output variables were tested using neural networks. An approach for converting linguistic terms into crisp numbers was used to incorporate linguistic variables into the quantitative neural network analysis. After a series of tests, results show that neural networks are capable of predicting risk patterns under all tested configurations of input and output variables, with a great deal of flexibility. Risk-based mathematical functions, be they linear or non-linear, can be re-modelled using neural networks. Finally, the paper concludes that the artificial neural networks serve as a promising risk decision support tool in natural hazards. 相似文献
405.
Philip Heilman Jerry L. Hatfield Martin Adkins Jeffrey Porter Russell Kurth 《Journal of the American Water Resources Association》2004,40(2):333-345
ABSTRACT: Water quality issues in agriculture are growing in importance. A common theme is the provision of better information to decision makers. This study reports the trial of a prototype decision support system by the U.S. Department of Agriculture Natural Resources Conservation Service and the Agricultural Research Service in the NRCS Harrison County Field Office in 1998. Observed data collected at the Deep Loess Research Station (DLRS) near Treynor, Iowa, were extrapolated using a modified GLEAMS field scale simulation model that included a nitrogen leaching component and a crop growth component. An accounting tool was used to convert crop yield estimates into crop budgets. A model interface was built to specify the climate, soil, and topography of the field, as well as the management scenarios for the alternative management systems. For the Deep Loess Hills area of Harrison County, a total of six soil and slope groups, with 66 total combinations of management practices forming management systems, were defined and simulated based on previously calibrated data from DLRS. A multi‐objective decision support system, the Water Quality Decision Support System, or WQDSS, was used to examine the tradeoffs in a comprehensive set of variables affected by alternative management systems with farmers in Harrison County. The study concluded that a multiobjective decision support system should be developed to support conservation planning by the NRCS. Currently, a larger scale effort to improve water quality decision making is underway. 相似文献
406.
Während der Vorbereitungen zu diesem Artikel war R. L. J. als Preisträger der Alexander-von-Humboldt-Stiftung in Göttingen tätig. Unsere Forschung auf diesem Gebiet wurde durch großzügige Hilfe der Deutschen Forschungsgemeinschaft und der National Science Foundation (USA) ermöglicht. Außerdem sind wir B. Raufeisen für die Herstellung der Zeichnungen sehr zu Dank verpflichtet. 相似文献
407.
Russell G. Mein 《Journal of the American Water Resources Association》1980,16(5):824-829
ABSTRACT: A runoff routing model, originally developed for rural, areas and later adapted for application in urban areas, is shown to be, very suitable for use in design detention basin systems. The model, computes design inflow hydrographs for basins and routes flow through, basins to the next downstream point of interest. Some general conclusions are drawn on the effects of different basin configurations. 相似文献
408.
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410.
Richard Lowrance Lee S. Altier J. Denis Newbold Ronald R. Schnabel Peter M. Groffman Judith M. Denver David L. Correll J. Wendell Gilliam James L. Robinson Russell B. Brinsfield Kenneth W. Staver William Lucas Albert H. Todd 《Environmental management》1997,21(5):687-712
/ Maryland, Virginia, and Pennsylvania, USA, have agreed to reduce nutrient loadings to Chesapeake Bay by 40% by the year 2000. This requires control of nonpoint sources of nutrients, much of which comes from agriculture. Riparian forest buffer systems (RFBS) provide effective control of nonpoint source (NPS) pollution in some types of agricultural watersheds. Control of NPS pollution is dependent on the type of pollutant and the hydrologic connection between pollution sources, the RFBS, and the stream. Water quality improvements are most likely in areas of where most of the excess precipitation moves across, in, or near the root zone of the RFBS. In areas such as the Inner Coastal Plain and Piedmont watersheds with thin soils, RFBS should retain 50%-90% of the total loading of nitrate in shallow groundwater, sediment in surface runoff, and total N in both surface runoff and groundwater. Retention of phosphorus is generally much less. In regions with deeper soils and/or greater regional groundwater recharge (such as parts of the Piedmont and the Valley and Ridge), RFBS water quality improvements are probably much less. The expected levels of pollutant control by RFBS are identified for each of nine physiographic provinces of the Chesapeake Bay Watershed. Issues related to of establishment, sustainability, and management are also discussed.KEY WORDS: Riparian forest buffers; Chesapeake Bay; Nonpoint source pollution; Nitrogen; Phosphorus; Sediment 相似文献