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361.
Edward A. Keller Mark H. Capelli 《Journal of the American Water Resources Association》1992,28(5):813-832
ABSTRACT: On February 12, 1992, a portion of the Ventura River, California, flowed through the Ventura Beach RV Resort which had recently been constructed across a major historically active distributary of the Ventura River delta. State and local land-use planners recognized the flood hazards associated with the site, but decision-makers relied on analytical methods developed by the U.S. Army Corps of Engineers and flood-hazard categories developed by the Federal Emergency Management Agency, which did not adequately reflect the mobile nature of the Ventura River channel and distributaries. A better understanding of the historical behavior of the Ventura River could have averted the flood damages experienced in 1992. Low intensity recreational, agricultural, or habitat restoration use of the site would minimize potential flood damages and obviate the need for structural flood protection that would impact the river's natural resources. Continued operation of the recreational vehicle park could result in additional flood damages in the relatively near future; recognizing the limitations of the flood-modeling methodologies used for the Ventura Beach RV Resort could prevent similar miscalculations of flood potential in comparable situations. 相似文献
362.
Cooperation or conflict? Interagency relationships and the future of biodiversity for US parks and forests 总被引:1,自引:0,他引:1
R. Edward Grumbine 《Environmental management》1991,15(1):27-37
Cooperation between the United States Department of Agriculture (USDA) Forest Service and the United States Department of
Interior (USDI) National Park Service is most often advocated to protect biological diversity on national forests and parks,
but the agencies, so far, have done little to implement the biodiversity mandates of such laws as the Endangered Species Act
and the National Forest Management Act. The ideological and political history of the Forest Service and Park Service is explored
to determine the roots of interagency conflicts. Several recent models of cooperative reform are also critiqued and found
to be insufficient to stimulate better working relationships. To protect biodiversity, cooperation must be framed within conservation
biology and must place primary emphasis on ecosystem patterns and processes as well as on individual species. Increased education
of agency managers, ecosystem-level research, local and regional public participation, scientific oversight committees, new
legislation, and enlightened leadership also play important roles. Ultimately, management policies must be reframed within
a context of ecocentric values. 相似文献
363.
Bill Macaitis Stanley J. Povilaitis Edward B. Cameron 《Journal of the American Water Resources Association》1977,13(4):795-806
ABSTRACT: By United States Supreme Court action, the diversion of water from Lake Michigan and the Lake Michigan Drainage Basin in the Metropolitan Chicago Area is regulated at an annual maximum rate of 3,200 cfs. Approximately 1,700 cfs of this diversion is used for water supply, and the remaining 1,500 cfs consists primarily of stormwater runoff with lesser amounts of direct lake diversion, such as lockage and leakage, navigational makeup water flows, and discretionary diversion needed to maintain water quality standards in the Metropolitan Sanitary District of Greater Chicago's basic waterways. In order to assess the schedule of its discretionary diversion needs, the District, using a computer model of its basic waterway system, has calculated the minimum discretionary diversion requirements for projected water quality conditions as successive elements of the District's water pollution control program are completed. The results of these analyses can be used as a basis for developing plans for future allocations of the limited supply of Lake Michigan water to other uses such as domestic water supply, when and if such supplies become available. 相似文献
364.
W. Joseph Martin Edward L. Thackston 《Journal of the American Water Resources Association》1980,16(6):1006-1011
ABSTRACT: A retrospective benefit-cost analysis of major water resources projects in the Cumberland River basin was conducted. The U.S. Army Corps of Engineers' projects selected were Dale Hollow, Wolf Creek, Center Hill, and J. Percy Priest Reservoirs. The ex-post performance of the evaluated reservoirs were compared to the ex-ante estimates. Benefits and costs for each project were deflated to their base year and respective average annual values for each of these components were calculated. An ex-post benefit-cost ratio was determined for each project, as well as the combined system. The benefit-cost ratio for each project surpassed unity. The actual ratio as compared to the ex-ante estimate for each project is as follows: Dale Hollow, 1.24 to 1.46; Wolf Creek, 1.40 to 1.53; Center Hill, 1.17 to 2.02; and J. Percy Priest, 1.45 to 1.6. The internal rate of return was also determined for each project. The results obtained for each project are tabulated and discussed with consideration given to factors effecting the economic evaluation of the projects. 相似文献
365.
Tommy L. Brown Edward J. Finegan Michael P. Voiland 《Journal of the American Water Resources Association》1979,15(2):337-344
ABSTRACT: As the many recreational uses of waterways have intensified, management agencies have increasingly turned to water surface zoning techniques to provide safe, equitable opportunities while also protecting aquatic habitats. Other publications have described the concept of water surface zoning; the study reported on was conducted to determine its current use nationwide. Depending on jurisdiction of the water surface in question and state legislation to zone water surfaces, nonfederal zoning regulations sometimes emanate directly from state government, and sometimes involve direct state and local government cooperation. Results of a national survey show that water surface zoning techniques employed by state and local governments in 1976–77 fall into five broad categories: restrictions on boat speed and horsepower, special use zoning, time zoining, protective space zoning, and limited density zoning. Examples of each are reported on in this paper. 相似文献
366.
Edward R. Kaynor Irving Howards 《Journal of the American Water Resources Association》1971,7(6):1117-1127
Study of water resource decision-making in Massachusetts demonstrates the existence of many institutional constraints such as the established fee system for consulting engineers, the funding of certain agencies, the institutionalization of equity concerns, overrepresentation of interests, and incompatibility of agency goals. These institutional constraints are attributable in part to certain broadly-based value-orientations such as the American pragmatic tradition. However, various lines of evidence indicate that these constraints are less important than other factors in the etiology of decisional outcomes. The outcomes of the decision processes were found to be at variance with the decisions studied, a fact leading to the conclusion that choice of decisions for study should be given more attention. The authors conclude that institutional constraints are important if one is interested in studying how decisions are made, but that what actually happens in the long run cannot be easily ascertained by studying either institutions or the decision-making process. They suggest the need for more research utilizing the incremental theories of Carl Lindblom and the side-effect theories of Albert O. Hirschman. 相似文献
367.
Jack A. Stanford Edward B. Reed 《Journal of the American Water Resources Association》1974,10(3):470-477
ABSTRACT: A colonization basket sampling technique for quantifying macroinvertebrates in rubble bottom rivers is described. Basket samplers were compared to collections made using the Surber square foot sampler. Procedure for processing samples is described. Macrobenthos were more accurately quantified by basket samplers because both surface and subsurface habitats were sampled, no organisms were lost when samplers were removed from the river, substrata and associated fauna were retained for analysis, and the samplers were used efficiently in both pool and riffle areas. At the end of the colonization period the basket samplers contained one-half cubic foot of river bottom and macroinvertebrates spatially arranged within. 相似文献
368.
Edward H. Bryan 《Journal of the American Water Resources Association》1972,8(3):578-588
ABSTRACT Urban storm water from a 1,067-acre drainage basin in Durham, N.C. was characterized to determine yield of pollutants. Population density averaged 9 persons per acre (ranging from <3 to 16). Annual BOD contribution attributable to surface wash during storms was determined to be approximately equal to contribution by its secondary wastewater treatment plant effluent. Total organic matter (COD) was estimated to exceed the amount in raw sanitary sewage from a residentially developed area of the same size. Mean basin yields (Ib/acre/day) were: BOD-0.23, COD-2.85, Total Solids-43.6, Volatile Total Solids-4.8, Total Phosphate-0.01 and Chloride-0.20 (as NaQ). The yield of lead presumed to originate from internal combustion engines operating on and near the basin was determined to be 0.006 Ib/acre/day. The concentration of total pesticides (Dieldrin; p,p'DDE; p,p-DDT; p,p'DDD and p,p'DDT) weighted for flow significance was estimated to be 1.2 parts per billion. The major long-term pollutional impact on a projected downstream reservoir was considered to be the fixed solids residue and long-term oxygen demand (COD). Intermittent release of other pollutants in slugs during runoff periods may be a significant factor in causing undesirable effects in streams draining urban areas. 相似文献
369.
Jerry L. Faulkner Edward E. C. Clebsch William L. Sanders 《Environmental management》1989,13(5):603-612
The purpose of this study was to provide the National Park Service with quantitative information regarding the effect of fire on fuel loads and pest species such asLonicera japonica, Ligustrum sinense, andRhus radicans.Three study areas of ten plots each were located in Chickamauga Battlefield Reservation of the Chickamauga and Chattanooga National Military Park. Fuel weights, aboveground biomass of honeysuckle, and counts of privet and poison ivy were collected both before and after prescribed fire. Additionally, one fourth of each of 14 plots was treated with glyphosate (tradename Roundup) to test for the use of fire as a herbicide pretreatment. This was a randomized block design with subsampling.Prescribed burning did significantly ( = 0.05) reduce fuel loads and the biomass of honeysuckle on burned plots. There was a statistically different response in fuel load reduction between fall and winter burns. Poison ivy significantly increased on burned plots, while privet counts did not vary significantly.Applications of glyphosate negatively impacted all three target species. Honeysuckle appeared to be damaged more readily on untreated plots, while no difference in response was noted on privet. Significantly more poison ivy growing points were killed by herbicide applications on burned plots than on unburned plots. 相似文献
370.
Eleftheria Katsivela Edward R. B. Moore Nicolas Kalogerakis 《Water, Air, & Soil Pollution: Focus》2003,3(3):103-115
Indigenous microorganisms, enriched and isolated from refinery waste sludge, were observed to possess a broad range of metabolic activities for mixtures of several classes of substrates of petroleum hydrocarbons, such as monoaromatic and polycyclic aromatic hydrocarbons (PAHs) and n- and branched alkanes. Three of the best-growing bacterial isolates selectively enriched with these compounds were identified by 16S rDNA sequencing as belonging to the genera Enterobacter and Ochrobactrum. Two of them, Enterobacter sp. strain EK3.1 and Ochrobactrum sp. strain EK6 utilise a hydrocarbon mixture of the branched alkane 2,6,10,14-tetramethylpentadecane and the PAHs acenaphthylene and acenaphthene. Enterobacter sp. strain EK4 can grow with a mixture of 2,6,10,14-tetramethylpentadecane, toluene, acenaphthylene and acenaphthene as carbon sources. Nucleic acid fingerprint analysis, by terminal restriction fragment length polymorphism (T-RFLP) of the PCR-amplified 16S rRNA genes, of the autochthonous bacterial community in contaminated soil samples showed complex and different community structures under different treatments of refinery waste sludge in landfarm areas. The characteristic peaks of the T-RFLP profiles of the individual, isolated degrading bacteria Enterobacter spp. and Ochrobactrum sp. were detected in the T-RFLP fingerprint of the bacterial community of the four months old treated landfarm soil, suggesting the enrichment of bacteria belonging to the same operational taxonomic units, as well as their importance in degrading activity. 相似文献