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491.
Arun S. Malik Bruce A. Larson Marc Ribaudo 《Journal of the American Water Resources Association》1994,30(3):471-480
ABSTRACT. The limited success of command-and-control policies for reducing nonpoint source (NPS) water pollution mandated under the Federal Water Pollution Control Act (FWPCA) has prompted increased interest in economic incentive policies as an alternative control mechanism. A variety of measures have been proposed ranging from fairly minor modifications of existing policies to substantial revisions including watershed-wide polices that rely on economic incentives. While greater use of economic incentive policies, such as environmental bonds and point/nonpoint source trading is being advocated in the reauthorization of the CWA, the expected effects of individual proposals will be modest. The characteristics of NPS pollution, namely uncertainty and asymmetrical information, underscores that there is no single, ideal policy instrument for controlling the many types of agricultural NPS water pollution. Some of the usual incentive-based policies, such as effluent taxes, are not well suited to the task. Individual incentive policies proposed for the reauthorized CWA, such as pollution trading or deposit/refund systems, are not broadly applicable for heterogeneous pollution situations. Economic incentive policies may be appropriate in some cases, and command-and-control policies will be preferable in others and may in fact complement incentive policies. 相似文献
492.
Bruce R. Roberts Sanford D. Kohorst Henry F. Decker Daniel Yaussy 《Environmental management》1995,19(5):735-739
Various cultivars of four cool-season grass types (tall fescue, fine fescue, perennial ryegrass, and Kentucky bluegrass) were
seeded in 0.34-liter plastic pots containing either composted sewage sludge [Com-Til2 (CT), Soil Magic2 (SM)] or composted yard mulch (YM). Plants were grown in the greenhouse for four weeks prior to measuring shoot biomass.
White most tall fescue cultivars showed more shoot growth on YM, perennial ryegrass cultivars generally grew better on SM.
Cultivars of fine fescue and bluegrass grew about the same on YM or SM, and slightly less on CT. With very few exceptions,
shoot biomass of individual cultivars was greater on either YM or SM than it was on CT. Within individual grass types, Pennlawn
(fine fescue), Pennant (perennial ryegrass), and Victa (Kentucky bluegrass) averaged consistently better growth on all three
composted media. For tall fescue, Aquara, Rebel II, and Monarch performed best on YM, SM, and CT, respectively. Bioaccumulation
of heavy metals did not occur in selective samples of shoot tissues collected from the grass types used.
This research was supported by National Science Foundation grant #8902053 to Buckeye Bluegrass Farms. The greenhouse studies
described in this paper were performed in conjunction with field tests conducted at Buckeye Bluegrass Farms. Requests for
information on field trials should be directed to H. F. Decker, Box 176, Ostrander, Ohio 43061, USA.
Use of trade names is for the reader's information only and does not imply endorsement over similar products of like properties. 相似文献
493.
Bruce N. Wilson J. William Brown 《Journal of the American Water Resources Association》1992,28(2):397-408
ABSTRACT: A generalized unit hydrograph method is developed and evaluated for ungaged watersheds. A key component in this method is the value of a dimensionless storage coefficient. Procedures to estimate this coefficient are given using calibrated values from 142 rainfall-runoff events gaged in watershed located mainly in the Eastern US. Only limited success was obtained in predicting this storage coefficient. Thirty-seven, independent rainfall-runoff events were used to test the proposed technique. The generalized unit hydrograph predicted the observed runoff hydrographs fairly well with considerable improvement in accuracy over the SCS dimensionless unit hydrograph. Approximately one-half of test storms had percent errors in predicted peak flow rates that were less than 34 percent compared to percent error of 88 percent with the SCS method. 相似文献
494.
Jeffrey C. Sutherland Robert M. Bruce 《Journal of the American Water Resources Association》1977,13(6):1215-1226
ABSTRACT: The East Lansing-Meridian Water and Sewer Authority studied a sand-gravel esker near the existing water treatment plant to determine its potential as an independent surface water supply. The nearby Red Cedar River was also investigated as a possible source of water for immediate treatment or for recharge of the esker. Although the bedrock aquifer (Grand River and Saginaw Formations) yields water adequate for the next 20 years, potential savings in treatment (hardness, iron) and pumping costs, estimated at $30,000 per year for present demand of 5 MGD, are attractive incentives for a surface water-esker recharge program. Operation savings would also be realized by constructing additional bedrock wells in new areas. The river-esker-recharge and new wellfield alternatives are compared for cost-effectiveness. Land costs make the recharge alternative more expensive. The land is undeveloped suburban property with potential for recreational use in conjunction with water supply. More places of outdoor retreat and aesthetics are needed in the Lansig Metropolitan area. A portion of the land costs would have to be borne by these or other interests for the river recharge scheme to be economically feasible. 相似文献
495.
496.
Bruce W. Lium W. Thomas Shoaf 《Journal of the American Water Resources Association》1980,16(2):359-360
ABSTRACT: Nine samples, each with different kinds and numbers of algae, were filtered at five pressures from 5 to 75 pounds per square inch and the amounts of chlorophylls a and b were measured. Pressures in the range tested had no effect on the measured amounts. 相似文献
497.
Regional-scale vegetation changes on Assateague Island following overwash from the Ash Wednesday Storm of 1962 were investigated using historical aerial photography. Grasses and dunes were more abundant in 1974 in areas that were overwashed, whereas areas that were not overwashed have been more extensively colonized by shrubs. The increase in shrubs on Assateague Island is attributed to the absence of a subsequent storm overwash. 相似文献
498.
Bhaskar J. Choudhury Bruce J. Blanchard 《Journal of the American Water Resources Association》1983,19(2):241-247
ABSTRACT: The antecedent precipitation index (API) has been a useful indicator of soil moisture conditions for watershed runoff calculations, and recent attempts to correlate this index with spaceborne microwave observations have been fairly successful. The prognostic equation for soil moisture used in some of the atmospheric general circulation models (GCM) together with Thomthwaite-Mather parameterization of actual evapotranspiration leads to API equations. The recession coefficient for API is found to depend on climatic factors as contained in potential evapotranspiration and to depend on soil texture as reflected by field capacity and permanent wilting point. A recently developed model for global insolation is used with climatological data for Wisconsin to simulate the annual trend of the recession coefficient. Good quantitative agreement is shown with the observed trends at Fennimore and Colby watersheds in Wisconsin. This study suggests that API could be a unifying concept for watershed and atmospheric general circulation modeling. 相似文献
499.
William H. Bruvold Bruce R. Smith 《Journal of the American Water Resources Association》1988,24(3):661-669
ABSTRACT: Relevant literature was reviewed from which a model of residential water conservation was developed. Four residential conservation program interventions were posited: 1) public education, 2) pricing variables, 3) water use restrictions, and 4) building code requirements. Four exogenous variables affecting residential water use were also posited: 1) temperature, 2) rainfall, 3) household income, and 4) household size. The impacts of these eight variables on residential per capita daily use were assessed by cross sectional and time series analysis. Study results generally supported the porposed model, with less consistent support obtained for pricing variables and conservation beliefs. The paper concludes with the hypothesis that an inclining block rate structure coupled with an informational program designed to inform consumers of their consumption under each block will have a synergistic impact. 相似文献
500.
Bruce Fox Mary Anne Keller Andrew J. Schlosberg James E. Vlahovich 《Environmental management》1989,13(1):75-84
Intellectual concern with the National Forest Management Act of 1976 has followed a course emphasizing the planning aspects of the legislation associated with the development of forest plans. Once approved, however, forest plans must be implemented. Due to the complex nature of the ecological systems of interest, and the multiple and often conflicting desires of user clientele groups, the feasibility and costs of implementing forest plans require immediate investigation. For one timber sale on the Coconino National Forest in Arizona, forest plan constraints were applied and resulting resource outputs predicted using the terrestrial ecosystem analysis and modeling system (TEAMS), a computer-based decision support system developed at the School of Forestry, Northern Arizona University, With forest plan constraints for wildlife habitat, visual diversity, riparian area protection, and soil and slope harvesting restrictions, the maximum timber harvest obtainable was reduced 58% from the maximum obtainable without plan constraints.Former Graduate Student at Northern Arizona University. 相似文献