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981.
Philip Irvin 《Journal of the American Water Resources Association》1986,22(4):597-599
ABSTRACT: The annual distribution of flow in a drainage basin within a given region is a function of many factors. These may include annual distribution of rainfall, basin orientation, ground cover, or presence of glaciers. Since the North Cascades region of northern Washington State has little variation in precipitation distribution by month, and the region has significant snowpack, one would predict that in an unregulated basin, basin elevation would be one of the most important factors impacting an annual hydrograph distribution. Such a prediction can be made since the higher a drainage basin is, the larger the portion of runoff that would occur as late spring snowmelt. Given that there is a relationship between elevation distribution and annual hydrograph, the problem becomes one of how to use this relationship to model an ungaged basin's hydrograph. This study concludes that, within the North Cascades region and perhaps within other regions, an effective method of determining annual flow distribution is to model ungaged flows in the same manner as flows from a gaged basin with an elevation distribution similar to that of the subject basin. 相似文献
982.
Jennifer M. Thomsen Susan C. Caplow 《Journal of Environmental Planning and Management》2017,60(7):1153-1172
Transboundary issues, like climate change, threaten the health of natural ecosystems. To address these problems, management is taking place at larger geographic scales and across political boundaries. Although landscapes are considered the suitable scale for conservation, limited research exists on how members of large landscape conservation organizations (LLCOs) define success. The Crown Managers Partnership (CMP) and the Southern Appalachian Man and the Biosphere Cooperative (SAMAB) are two LLCOs that support collaboration for the conservation of the Northern Rockies and the Southern Appalachian regions. We analyze the diverse interpretations of success among SAMAB and CMP participants during different stages of the organizations’ life cycle. Of particular importance is how members emphasize intangible successes such as relationships and the cascading effects LLCOs can have on other projects and organizations. This research provides insight into the distinct niche LLCOs fill in transboundary ecosystem management. 相似文献
983.
Frederic O. Sargent Philip R. Berke 《Journal of the American Water Resources Association》1979,15(3):826-837
ABSTRACT: Private lakeshore development usually precedes establishment of public lake access. As a result, the best access areas are often occupied before public access is provided. The public then has a problem to provide access for nonriparian citizens. This problem can be anticipated and prevented by classifying undeveloped lakeshore areas according to suitability for both private and public uses, and incorporating appropriate recommendations into the municipal, comprehensive land use plan. To accomplish this, a site evaluation system has been developed which numerically rates the lakeshore for each of four public uses: public beaches, picnic areas, boat access areas, and public marinas; and two private uses: private marinas and vacation homes. Ratings are developed for: slope, soil suitability, shoreland type, water quality, site location, scenery, and road access. These ratings are combined with a statement of public goals developed from attitude surveys to produce a lakeshore land use plan. The plan recommends that lakeshore areas best suited for private development are so used, and areas best suited for public use are reserved for that purpose. This site evaluation system is demonstrated by a case study on Lake Champlain in Ferrisburg, Vermont. 相似文献
984.
In its role as a competitive producer of phosphate and potash Jordan has not suffered noticeably from the Resource Curse over the past 50 years. However, the effects on its economy because of its geographical proximity to major oil-producing states have been both positive and negative. It is arguable that an oil resource curse has applied to Jordan. 相似文献
985.
Sediment mantling the floor of Sydney estuary contains a wide range of chemicals at highly elevated concentrations over extensive
areas. Appropriate sediment management decisions are urgently required to prevent further degradation of sediment quality
and to minimize resulting adverse ecological effects. The objective of the present work was to provide a systematic, estuary-wide
assessment of sediment risk and ecological/conservation value throughout the harbor to guide sediment management decisions.
Sediment risk is the likelihood of sediment chemistry causing adverse biological effects to bottom-dwelling animals and was
conducted using national sediment quality guidelines (SQGs) for single contaminants and the mean SQG quotient approach to
assess chemical mixtures. Sediment risk was negligible at the mouth of the estuary, but increased strongly landwards. The
ecological/conservation value assessment was conducted to identify sites that warrant different levels of protection and was
conducted using the value of ecological communities and priority waterway use. Consideration of these two parameters combined
enabled the estuary to be prioritized for management attention. The prioritization and identification of appropriate management
strategies were determined through the use of management matrices also based on sediment risk and ecological/conservation
value. A computer package is being developed to provide managers with information on sediment risk, ecological/conservation
value, the urgency and the type of management intervention required for any location in Sydney estuary, in real-time. This
approach to estuarine management is unique and will greatly improve effective management of Sydney estuary, and other harbors
in urgent need of management action and protection. 相似文献
986.
White PC Newton-Cross GA Moberly RL Smart JC Baker PJ Harris S 《Journal of environmental management》2003,67(2):187-197
There is increasing concern about the use of lethal methods to control wild mammal populations, especially those methods that may have significant impacts on animal welfare. The continued use of dogs to hunt wild mammals in England and Wales, principally foxes (Vulpes vulpes), red deer (Cervus elaphus), brown hares (Lepus europaeus) and mink (Mustela vison), has become a focus for political debate and has been the subject of a recent UK government inquiry. This paper reports the results of a questionnaire study to quantify the use, effectiveness and acceptability of the different methods currently used to manage these four species, and future changes in management following a possible ban on hunting with dogs. There was no straightforward relationship between culling pressure and perceived pest status of the different species from the questionnaire data. For foxes and brown hares, the proportion of land managers (practitioners) carrying out lethal control was higher than that considering these species to be pests. However, the reverse was the case for mink. The most frequently used and effective control methods, which were most acceptable to practitioners and public alike, were various forms of shooting. The general public perceived hunting with dogs as one of the least acceptable means of control for all four species. Practitioners thought that hunting with dogs for red deer and the use of terriers against foxes were among the least acceptable forms of control, but considered hunting with dogs in other situations and for other species to be relatively acceptable. Most practitioners said a ban on hunting with dogs would make no difference to their management of the four species. A ban on hunting with dogs would have minimal impact on populations of foxes, red deer and mink, but it may be of conservation benefit to hares. 相似文献
987.
The fate of manure nutrients in beef cattle (Bos taurus) feedlots is influenced by handling treatment, yet few data are available in western Canada comparing traditional practices (fresh handling, stockpiling) with newer ones (composting). This study examined the influence of handling treatment (fresh, stockpiled, or composted) on nutrient levels and mass balance estimates of feedlot manure at Lethbridge, Alberta, and Brandon, Manitoba. Total carbon (TC) concentration of compost (161 kg Mg(-1)) was lower (P < 0.001) than stockpiled (248 kg Mg(-1)), which was in turn lower (P < 0.001) than fresh manure (314 kg Mg(-1)). Total nitrogen (TN) concentration was not affected by handling treatment while total phosphorus (TP) concentration increased with composting at Lethbridge. The percent inorganic nitrogen (PIN) was lower (P < 0.01) for compost (5.1%) than both fresh (24.7%) and stockpiled (28.9%) manure. Composting led to higher (P < 0.05) dry matter (DM) losses (39.8%) compared to stockpiling (22.5%) and higher (P < 0.05) total mass (water + DM) losses (65.6 vs. 35.2%). Carbon (C) losses were higher (P < 0.01) with composting (66.9% of initial) than with stockpiling (37.5%), as were nitrogen (N) losses (46.3 vs. 22.5%, P < 0.05). Composting allowed transport of two times as much P as fresh manure and 1.4 times as much P as stockpiled manure (P < 0.001) on an "as is" basis. Our study looked at one aspect of manure management (i.e., handling treatment effects on nutrient concentrations and mass balance estimates) and, as such, should be viewed as one component in the larger context of a life cycle assessment. 相似文献
988.
Gordon G. Park Philip S. Schmidt 《Journal of the American Water Resources Association》1973,9(5):932-941
ABSTRACT: A numerical model study of thermal stratification in a high discharge-to-volume reservoir is described. Predicted temperature profiles are compared with field data for two different years. The model accurately predicts the date of fall turnover, and predicts degree of stratification and depth of the thermocline within about 20% for both years simulated. A parametric study of stratification mechanics for a high flow reservoir indicated that diffusion was the predominant heat transport mechanism in the hypolimnion, while surface effects dominated the epilimnion. Flow effects for the particular case studied, in which all inflows and outflows occur in the epilimnion, did not significantly affect stratification behavior. 相似文献
989.
990.
Natural hazard investigators recommend that local governments adopt mitigation plans to help reduce hazard losses. However,
such plans are unlikely to be effective unless a wide range of public stakeholders is involved in their creation. Previous
research shows that stakeholder participation levels in hazard mitigation planning tend to be low, though there may be particular
choices that local government planners can make to foster participation. We examine the importance of planners’ choices and
role orientations (i.e., beliefs regarding appropriate behavior in the workplace) for participation levels in site plan review,
wherein local governments review site plans for proposed development projects to ensure compliance between project design
and applicable plans and policies. Using a national sample of 65 development projects located in areas subject to natural
hazards, and bivariate and multivariate analyses, we examine whether participation levels during site plan review depend upon
planners’ choices and role orientations, and whether participation levels are correlated with the incorporation of hazard
mitigation techniques into development projects. We find significant correlations between participation levels and planners’
choices, between participation levels and planner’s role orientations, and between participation levels and the incorporation
of hazard mitigation techniques. We encourage local government planners to revisit their beliefs, choices, and behaviors regarding
public participation in site plan review. 相似文献