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941.
B. Lussier G. E. Mohr I. C. Goulter 《Journal of the American Water Resources Association》1989,25(1):111-116
ABSTRACT: The techniques of conflict analysis derived from game theory were applied to the Shoal Lake water supply conflict in southeastern Manitoba, Canada. The issue of conflict is the desire of an Indian Band in the area to build cottage lots near the intake for water supply for the City of Winnipeg. The City of Winnipeg contends that such a development would seriously affect the quality of water supplied to the City, thereby increasing its treatment costs significantly. The four major players defined for the conflict are the City of Winnipeg, Indian Band No. 40, the Province of Manitoba, and the Federal Department of Indian and Northern Affairs. The results of the conflict analysis suggest that the introduction of the provincial and federal government into the conifict will not assist significantly in its resolution and that further progress on the resolution is unlikely until the results of Federal Environment Assessment Review office hearing become available. 相似文献
942.
In this paper, a mechanical filtering system to treat pig slurry is proposed. The filter was made from the aerobic decomposition product of the organic fraction of municipal wastes and wheat straw was used as the support.Using a pilot plant to treat 2100 liters of swine slurry, an adequate reduction in BOD5; COD, and other parameters was obtained. The organic matter content of the material trapped in the filter was similar to that of compost and farmyard manure, but the nitrogen and phosphorous levels and the C/N ratio were more similar to farmyard manure. After passing through a filtering system, the treated liquid can be used for fertirrigation and as a feed for algae ponds. After a period of stabilization, the solid material can be mixed to produce manure. Although wheat straw was used as the support in this experiment, other agricultural wastes such as rice straw, corn stalks, millet stems, banana, cotton, and coconut trash can be used. Rather than municipal solid waste compost, other kinds of compost obtained from agricultural wastes such as leaves, bark, husks, etc., can be used as the filter. 相似文献
943.
Salmon farming is a rapidly expanding industry. In order for it to develop in an ethical manner, many ethical issues must be confronted. Among these are questions regarding the quality of life of salmon on farms. To develop reasonable answers to these questions considerable thought must be devoted to developing appropriate standards of care for salmon. If these questions are not addressed the results could be bad both for salmon and for salmon farmers. 相似文献
944.
William F. Porter Nancy E. Mathews H. Brian Underwood Richard W. Sage Jr. Donald F. Behrend 《Environmental management》1991,15(6):809-814
Populations of white-tailed deer (Odocoileus virginianus) inhabiting many state and national parks and suburban areas have grown to the point that they conflict with human activities.
Conflicts range from destruction of vegetation through browsing to public perception that diseases carried by deer pose threats
to human health. Traditional modes of hunting to control populations are inappropriate in many of these areas because of intense
human development and activity. This article explores an alternative approach for population reduction based on deer social
organization. Female white-tailed deer are highly philopatric and female offspring remain near their dams for life. This suggests
that a population expands slowly as a series of overlapping home ranges in a form analogous to the petals on a rose. Incorporating
the rose petal concept into a model of population growth shows that removal of deer by family unit can potentially alleviate
conflicts in localized areas for as many as 10–15 yr. 相似文献
945.
James W. Male John B. Moriarty Thomas H. Stevens Cleve E. Willis 《Journal of the American Water Resources Association》1991,27(3):521-526
ABSTRACT: This paper examines the cost of water supply for small and mid-sized private water utilities. An econometric approach was employed in which data on utility costs and characteristics were used to estimate a total water supply cost function from which average and marginal costs were derived. The results suggest that although average and marginal costs decline with output, the rate of decline rapidly approaches zero, and unit costs therefore appear to remain relatively constant over a wide range of output. Implications of the results for pricing policy are examined. 相似文献
946.
G. N. Rao J. N. Beck H. E. Murray D. J. Nyman 《Journal of the American Water Resources Association》1991,27(1):47-58
ABSTRACT: Specific capacity data obtained from Well Construction reports which are available from USGS offices, can provide useful estimates of tranamissivity (T), and hydraulic conductivity (K), of an aquifer. The Chicot Aquifer in Louisiana is one of the largest sources of fresh ground water in North America. Hydrologic data collected for the Chicot Aquifer indicate that specific capacity tests can be used in estimating local and regional values for T and K, if the Cooper-Jacob equation for transient flow is used with proper corrections for well loss and partial penetration. Where full scale pumping test data are scarce, specific capacity test data that are adequately distributed spatially can be used to map changes in T and K values and can be summarized statistically to indicate applicable regional values. A computer program called “TGUESS” which is available from International Ground Water Modeling Center, Holcomb Research Institute, was used in this study. The contour maps for T and K values are prepared for different well depth intervals to avoid wide variation of values. 相似文献
947.
Graham A. Tobin Burrell E. Montz 《Journal of the American Water Resources Association》1994,30(4):673-685
ABSTRACT: Literature on the flood hazard/residential land market relationship is full of contradictory findings, many of which are counter-intuitive to the belief that flooding has a negative impact on house prices. This research advances a conceptual framework through which these relationships might be re-examined. Based on the expected utility model, the theoretical framework integrates the economic notion of capitalization with spatial and temporal characteristics of the flood hazard. Four communities with different flood regimes are used to test the effect of flooding on the residential real estate market. Results show that, (1) there is an identifiable relationship between characteristics of the flood hazard and changes in house values; (2) the length of the recovery period is dependent on characteristics and expectations of flooding, attributes of the real estate market, and availability of capital to fuel recovery; and (3) dynamics of the urban market and spatial extent of the flood hazard influence these relationships. Further research is now necessary to examine these findings under different spatial, temporal, hydrological, and socio-economic conditions. 相似文献
948.
949.
950.
Christian Roy Bruno de Caumia Daniel Blanchette Hooshang Pakdel Genevive Couture Annette E. Schwerdtfeger 《补救:环境净化治理成本、技术与工艺杂志》1994,5(1):111-130
A vacuum pyrolysis process was used for the remediation of hydrocarbon–contaminated soils from “Les Vidangeurs de Montréal” site in Mascouche in the province of Québec, near Montréal. Ten samples were tested on a laboratory scale batch reactor, and one sample was tested on a prototype process development unit. The process is simple, efficient, reliable, and economically competitive with other existing technologies. The vacuum pyrolysis process efficiently treated soils contaminated with a variety of pollution levels and types, irrespective of the soil matrix, providing treated soils meeting the A criterion (noncontaminated, residential level) of the Ministry of Environment Québec (MENVIQ). The pyrolytic oil and the noncondensable pyrolytic gases can be used as makeup fuel in the process, because they have a high calorific value and their combustion should not pose any emission problems. The waterphase effluent must be treated before discharge. 相似文献