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991.
ABSTRACT: This paper describes the integration of a comprehensive hydrological model known as the Hydrological Simulation Program Fortran (HSPF) into a problem solving environment (PSE) for watershed management. The original PSE concept was a structure providing web‐based access to a suite of models, including HSPF and other models of in‐stream hydrodynamics, biological impacts and economic effects, for the watershed‐wide assessment of alternative land use scenarios. The present paper describes only the HSPF integration into the PSE program. Example applications to the 148 square kilometer (57 square mile) Back Creek subwatershed in the upper Roanoke River system (1,479 square kilometers or 571 square miles) in southwest Virginia are used to illustrate important concepts and linkages between land development and hydrological change using hypothetical' what if'scenarios. The features of HSPF and its limitations in this context are discussed. The paper as such is a proof‐of‐concept paper and not a completion report. It is intended to describe the PSE tool building process rather than analysis of the many possible simulation outcomes. However, the dominance of raw imperviousness as a contributor to hydrograph response is apparent in all the PSE simulations described in this paper.  相似文献   
992.
ABSTRACT: Watershed stewardship activities throughout North America have evolved into a process that requires more involvement in planning and decision making by community stakeholders. Active involvement of all stakeholders in the process of watershed stewardship is dependent on effective exchange of information among participants, and active involvement of a wide range of stakeholders from “communities of place” as well as those from “communities of interest.” We developed a map‐based stream narrative tool as a means to: (a) assemble a wealth of incompletely documented, “traditional” ecological or natural history observations for rivers or streams; and (b) promote a higher level of active involvement by community stakeholders in contributing to information‐based, watershed management. Creation of stream narratives is intended for use as a tool to actively engage local stakeholders in the development of a more comprehensive information system to improve management for multiple stewardship objectives in watersheds. Completion of map‐based stream narrative atlases provides a valuable supplement to other independent efforts to assemble observations and knowledge about land‐based natural resources covering entire watersheds. We are confident that completion of stream narrative projects will make a valuable addition to the information and decision making tools that are currently available to the public and resource agencies interested in advancing the cause of community‐based approaches to watershed and ecosystem management.  相似文献   
993.
ABSTRACT: River Environment Classification (REC) is a new system for classifying river environments that is based on climate, topography, geology, and land cover factors that control spatial patterns in river ecosystems. REC builds on existing principles for environmental regionalization and introduces three specific additions to the “ecoregion” approach. First, the REC assumes that ecological patterns are dependent on a range of factors and associated landscape scale processes, some of which may show significant variation within an ecoregion. REC arranges the controlling factors in a hierarchy with each level defining the cause of ecological variation at a given characteristic scale. Second, REC assumes that ecological characteristics of rivers are responses to fluvial (i.e., hydrological and hydraulic) processes. Thus, REC uses a network of channels and associated watersheds to classify specific sections of river. When mapped, REC has the form of a linear mosaic in which classes change in the downstream direction as the integrated characteristics of the watershed change, producing longitudinal spatial patterns that are typical of river ecosystems. Third, REC assigns individual river sections to a class independently and objectively according to criteria that result in a geographically independent framework in which classes may show wide geographic dispersion rather than the geographically dependent schemes that result from the ecoregion approach. REC has been developed to provide a multiscale spatial framework for river management and has been used to map the rivers of New Zealand at a 1:50,000 mapping scale.  相似文献   
994.
Public opinion and siting solid waste landfills in Kuwait   总被引:1,自引:0,他引:1  
Siting municipal solid waste landfills in Kuwait had not considered public concerns about the location of such facilities. Kuwait Municipality has disposed urban waste in abandoned sand quarries for the past 20 years in an unplanned fashion. Due to this improper siting criteria, environmental and health problems have risen from old landfills that are located in residential areas. In an effort to help responsible decision-makers in assessing public support for siting landfills a structured, yet simple, questionnaire was designed and distributed to a random sample of heads of households. Statistical techniques were employed to examine trends and relationships between the sample public responses concerning landfill siting criteria. The findings of the research indicated that a significant percentage of the responding sample did not know about the various landfill impacts and less than 50% were aware of the negative impacts of landfills on the public health and the environment. The visual appearance of the landfill scored the lowest impact in the opinion of the sample public while the most important aspect in siting a landfill appeared to be its economic consideration. The research findings also directed attention to the important role that the media could play in increasing public awareness. Results from the cross-classification analysis demonstrated the existence of differences in awareness levels according to age, nationality, martial status, education, and occupation of the responding sample. Statistically, these differences were significant at the 95% significance level, as supported by the test of the χ-square.  相似文献   
995.
This paper examines the process of establishing a coastal forum in the North West region of England. The North West Coastal Forum is one of the first attempts at the establishment of a regional forum in England and is especially notable for the role played by the Government Office for the North West in its formation. The paper examines the relationships between the key agencies involved and, in particular, the key role played by the Government Office for the North West in promoting and establishing the forum and how this has influenced its organization, structure and composition. It provides a critical analysis of the apparent and potential strengths and weaknesses of the forum as an example of a partnership approach to the planning and management of coastal issues in the North West. The conclusions are not only of relevance to the future development of the forum within the North West of England, and to the potential establishment of similar coastal fora elsewhere, but are also of much broader interest as a case example of the development of institutional capacities and collaborative partnership approaches to planning issues at the regional level in the wider context of the changing nature of regional governance in the UK and the enhanced 'regional partnership' role being embraced by the government offices for the regions.  相似文献   
996.
Summary In the past, the water supply and sewage services for the urban regions of developing countries have been provided, in the main, only for the more affluent areas of these cities. This paper, dealing especially with those countries with tropical monsoon climates, advocates the construction of more comprehensive systems.Experience drawn from a wide range of projects and a review of the relevant literature provokes the authors to emphasise the need for suitable manuals of appropriate technology for use in these developing countries. These manuals should provide a full set of environmental guidelines for the design of water supply and sewage/sanitation systems for use in these countries.Dr Harvey F. Ludwig is Chairman and Greg Browder is Environmental Engineer for SEATEC International Consulting Engineers, Bangkok, Thailand.  相似文献   
997.
Book reviews     
Baker  Ilyas  Kassas  M.  Bandler  Hans  Lisowski  Marylin  Disinger  John F.  Duthie  David  Briggs  K. B. 《The Environmentalist》1992,12(4):291-304
Environment Systems and Decisions -  相似文献   
998.
ABSTRACT: Texans participate directly in water policy decision-making through a referendum process involving amendment of the state's constitution. Prior to 1985, Texans voted on eight amendments. Five of these were ratified (1957, 1962, 1966, 1971, 1976), and collectively resulted in the creation of the Water Development Fund, with an authorization level of $600 million, and the Texas Water Development Board, the organization charged with administering the fund. Three other amendments were defeated in 1969, 1976, and 1981 by ever-increasing margins. From 1985 to 1991, six additional amendments were proposed and subsequently ratified, resulting in a $1.8 billion increase in Water Development Fund authorization and the creation of an agricultural water conservation fund and bond insurance program. County-level electoral data for the 1985–1991 referenda were mapped to assess sectional and regional factors underlying public opinion regarding these water resource development and funding programs. Regional contrasts were most pronounced for the 1989 and 1991 referenda that targeted economically distressed areas across the state, particularly the colonias located along the Rio Grande, and the 1989 amendment that removed a time limit on the issuance of agricultural water conservation bonds. As a specific case study, the Texas experience could serve as a guide in California where similar constitutional restrictions require tax and spending programs to be approved by voters, and in other states that may be considering the development of similar state-level financial programs for water projects.  相似文献   
999.
ABSTRACT: Landsat satellite Thematic Mapper (TM) data were used to assess regional soil moisture conditions. The mid-infrared (MIR) data of TM band 7 were overlain onto four principal land-use categories (Agricultural/Irrigated, Urban/Clearings, Forest/ Wetlands, Water) using a geographic information system (GIS). M data were used to assess four qualitative surface soil-moisture conditions (water/very wet, wet, moist, and dry) within each land-use category of a 208,354 ha southwestern Florida study area. The MIR response was inversely related to the qualitative surface soil-moisture content. Integration of Landsat TM MIR data with land use through GIS appears to be a useful technique for high-resolution regional soil moisture assessment, and further research to reline this technique is recommended.  相似文献   
1000.
Over the last several years, the inhalation of decay products coming from radon-222 has become a national health concern. It is estimated that somewhere between 16,000 and 20,000 people die annually in the United States from lung cancer due to exposure to these decay products. Nationwide, 95% of all homes have not been tested for radon, and so it would seem that any methodology that could give a general idea of indoor radon concentrations (without actually testing the house itself) might be useful. While not intended to replace a radon test, which is both simple and inexpensive, our project attempts to predict indoor radon concentrations based on easily obtainable information from Soil Conservation Service county soil surveys and US Geological Survey surficial geology maps. We have chosen four parameters: soil permeability, surficial geology, soil shrink-swell potential, and distance to the nearest geologic fault. Of these four variables, surficial geology and distance to fault correlated well to winter indoor radon concentrations as measured by short-term (48-h) tests. While it is understood that there are limits to this methodology, primarily because of map scale problems, the correlations mentioned above were very strong and suggest further study would be useful.  相似文献   
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