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991.
992.
F. Andrew. Schoolmaster 《Journal of the American Water Resources Association》1992,28(3):495-505
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
993.
Sun F Shih Jonathan D. Jordan 《Journal of the American Water Resources Association》1992,28(4):713-719
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
994.
Scott D. Lindsey Robert W. Gunderson J. Paul. Riley 《Journal of the American Water Resources Association》1992,28(5):865-875
ABSTRACT: Many hydrologic models have input data requirements that are difficult to satisfy for all but a few well-instrumented, experimental watersheds. In this study, point soil moisture in a mountain watershed with various types of vegetative cover was modeled using a generalized regression model. Information on sur-ficial characteristics of the watershed was obtained by applying fuzzy set theory to a database consisting of only satellite and a digital elevation model (DEM). The fuzzy-c algorithm separated the watershed into distinguishable classes and provided regression coefficients for each ground pixel. The regression model used the coefficients to estimate distributed soil moisture over the entire watershed. A soil moisture accounting model was used to resolve temporal differences between measurements at prototypical measurement sites and validation sites. The results were reasonably accurate for all classes in the watershed. The spatial distribution of soil moisture estimates corresponded accurately with soil moisture measurements at validation sites on the watershed. It was concluded that use of the regression model to distribute soil moisture from a specified number of points can be combined with satellite and DEM information to provide a reasonable estimation of the spatial distribution of soil moisture for a watershed. 相似文献
995.
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
996.
John F. Potter 《The Environmentalist》1993,13(3):161-163
997.
Environmental planning,ecosystem science,and ecosystem approaches for integrating environment and development 总被引:3,自引:0,他引:3
D. Scott Slocombe 《Environmental management》1993,17(3):289-303
Currently popular concepts such as sustainable development and sustainability seek the integration of environment and development
planning. However, there is little evidence that this integration is occurring in either mainstream development planning or
environmental planning. This is a function of the history, philosophies, and evolved roles of both. A brief review of the
experience and results of mainstream planning, environmental planning, and ecosystem science suggests there is much in past
scientific and professional practice that is relevant to the goal of integrated planning for environment and development,
but still such commonly recommended reforms as systems and multidisciplinary approaches, institutional integration, and participatory,
goal-oriented processes are rarely achieved. “Ecosystem approaches,” as developed and applied in ecology, human ecology, environmental
planning, anthropology, psychology, and other disciplines, may provide a more transdisciplinary route to successful integration
of environment and development. Experience with ecosystem approaches is reviewed, their advantages and disadvantages are discussed,
and they are compared to traditional urban and regional planning, environmental planning, and ecosystem science approaches.
Ultimately a synthesis of desirable characteristics for a framework to integrate environment and development planning is presented
as a guide for future work and a criterion for evaluating existing programs. 相似文献
998.
Total Quality Management provides a powerful management foundation and framework to implement an organization's environmental vision and principles. The elements of TQM include customer/stakeholder focus, a high degree of senior management commitment, a long-term focus, and tools such as continuous improvement, empowerment, and a prevention-based approach. This article describes a matrix developed by major U.S. and Canadian firms that serves as (1) a guide to organizations implementing TQEM from the ground floor up and (2) an assessment tool that can be used internally or externally to measure progress toward environmental management excellence and to identify opportunities for improvement. The matrix is based on categories adapted from those used in the Malcolm Baldrige National Quality Award process. The relationship between individual matrix cell criteria and key concepts such as pollution prevention and sustainability is also described. 相似文献
999.
1000.
Robert N. Havis Carlos V. Alonso John G. King Russell F. Thurow 《Journal of the American Water Resources Association》1993,29(3):435-444
ABSTRACT: A simulation model [Salmonid Spawning Analysis Model (SSAM)] was developed as a management tool to evaluate the relative impacts of stream sediment load and water temperature on salmonid egg survival. The model is useful for estimating acceptable sediment loads to spawning habitat that may result from upland development, such as logging and agriculture. Software in common use in the USA were adapted for use in gravel bedded rivers and linked to simulate water temperature (the USFWS Instream Water Temperature, SNTEMP model) and water and sediment routing (the USAE Scour and Deposition in Rivers and Reservoirs, HEC-6 model, version 3.2). These models drive the redd (spawning nest) model (the USDA-ABS Sediment Intrusion Dissolved Oxygen SIDO model) which simulates sediment intrusion and dissolved oxygen concentration in the redd environment. The SSAM model predictions of dissolved oxygen and water temperature compared favorably with field data from artificial redds containing hatchery chinook salmon eggs. 相似文献