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201.
Water scarcity is increasing internationally and now is also affecting the natural water resources of New Zealand. This paper explores two solutions at a local level—water-storage and water-sharing regimes—that address the problems of water scarcity and competition for water, towards more sustainable development. Both systems show positive effects on the local economy and for the local community, providing additional jobs to the region and increasing the value added. Environmental benefits mostly relate to a lessening of the impacts of water abstraction by keeping flow volumes above minimum requirements. Locally operated water-storage and water-sharing schemes thus can provide excellent governance strategies for water management, ensuring that local interest and issues are addressed adequately. 相似文献
202.
Recent years have seen the environment emerge as one of the most pressing issues facing American business. Eventually, environmental costs will affect the bottom line of every American company. A recent study in the National Law Journal estimates that cleanup of the nation's known hazardous wastes sites will cost $752 billion over thirty years under current environmental policies. Environmental legislation and regulations impose annual compliance costs estimated by the Environmental Protection Agency at more than $30 billion. In the near future, environmental expenses for cleanup, regulatory compliance, and management are anticipated to grow to between 2.5 and 3 percent of GNP. Corporations that wish to be competitive must successfully manage these costs while maintaining or improving their role as responsible corporate citizens. Implementing a comprehensive system for identifying and managing environmental costs requires a multidisciplinary team effort. Environmental costs impact product selection, design and pricing, capital budgeting, and future strategic direction. In order to make informed and meaningful managerial decisions on environmental programs, real cost data are vital. An environmental management systems (EMS) requires information to set goals and then monitor progress towards those goals over time. This article will discuss the current cost accounting systems (CASs) available to support the myriad goals of environmental management systems. In addition, the article will outline a framework for plotting the location of your current EMS on a matrix of regulatory and information requirements and evaluating whether your corporation's CAS is adequate to support the goals and objectives set by your environmental management program. By anticipating future regulatory and information requirements, flexible systems can be developed to adapt to new and more stringent regulations and more complex information requirements. 相似文献
203.
Russell Schoof 《Journal of the American Water Resources Association》1983,19(1):15-21
ABSTRACT: West Bitter Creek floodwater retarding structure site 3 in South Central Oklahoma was instrumented and records obtained and analyzed to obtain information concerning an impoundment water budget that is useful to landowners and designers of these impoundments. On-site loss of water from the impoundment was only 17 percent of the inflow during three years when the annual precipitation averaged 26 inches and the annual inflow averaged 1.4 inches. Runoff from an eroded area with no farm ponds was about 70 percent greater per unit area than from a portion of the watershed where 71 percent of the drainage area was controlled by farm ponds. A previous study indicated, however, that the ponds were reducing runoff only 13 percent. Loss of top soil increases runoff considerably. Only 24 percent of the total runoff into the impoundment was base flow. The flow rate into the impoundment was less than 0.05 cfs 70 percent of the time, and the inflow rate exceeded 10 cfs only 1 percent of the time. SCS runoff curve numbers varied between 57 and 96 for the impoundment watershed with an inverse relation between precipitation amount and curve number apprently caused by partial area runoff from impervious and semi-impervious areas. A comparison of measured event runoff versus event runoff computed by the SCS curve numbers gave an r2 of only 0.44. However, the total computed surface runoff for eight years of record was less than 1 percent below the measured runoff which indicated the curve number method was a good tool for predicting long term runoff for the watershed. 相似文献
204.
Summary Checker-throated antwrens (Formicariidae: Myrmotherula fulviventris) live in lowland neotropical forests and forage from dead curled leaves in the understory. Because they search each leaf individually they provide an opportunity to study the use of potential visual cues by an insectivorous bird. Long and highly curled leaves contain the most arthropods and checker-throated antwrens were more successful when foraging at those leaves. Yet, they used leaves at random with respect to these potential cues. Antwrens spent longer searching for arthropods in each highly curled leaf than in less curled leaves. Because of this additional search time, prey capture success per unit foraging time was only slightly greater for highly curled leaves than at the average dead leaf in the aerial leaf litter. Thus, the cues that antwrens could use to locate richer leaves are those features that obscure the prey from avian predators. Unlike other foraging systems, the antwrens appear to have no reliable cues indicating more profitable foraging sites.Address for correspondence 相似文献
205.
206.
This article presents an analysis of the prospective costs of RCRA corrective action for private, nonfederal facilities. Two data bases developed by Research Triangle Institute and a remedial action cost model developed by CH2M Hill provide the foundation for this work. The methodology has two components, a remedial action knowledge base and a discrete-state Monte Carlo analysis. Under base case assumptions, it is estimated that the total costs of RCRA corrective action will be $240 billion, with a 5 percent chance the costs will be less than $170 billion and a 5 percent chance the costs will be more than $377 billion. 相似文献
207.
208.
Relationships among Isolated Wetland Size, Hydroperiod, and Amphibian Species Richness: Implications for Wetland Regulations 总被引:6,自引:0,他引:6
Joel W. Snodgrass †‡ Mark J. Komoroski † A. Lawrence Bryan JR. † Joanna Burger 《Conservation biology》2000,14(2):414-419
Abstract: Wetland development within the United States is regulated primarily by size. Decisions concerning wetland destruction or conservation are therefore based in part on three inherent assumptions: (1) small wetlands contain water for short portions of the year; (2) small wetlands support few species; and (3) species found in small wetlands are also found in larger wetlands. We tested these assumptions using data on wetland size, relative hydroperiod (drying scores), and relative species richness of amphibians in depression wetlands of the southeastern United States. We found a significant (p = 0.03) but weak (r2 = 0.05) relationship between hydroperiod and wetland size and no relationship (p = 0.48) between amphibian species richness and wetland size. Furthermore, synthetic models of lentic communities predict that short-hydroperiod wetlands support a unique group of species. Empirical investigations support this prediction. Our results indicate that hydroperiod length should be included as a primary criterion in wetland regulations. We advocate a landscape approach to wetlands regulation, focused in part on conserving a diversity of wetlands that represent the entire hydroperiod gradient. 相似文献
209.
On the Decline of the Rusty Blackbird and the Use of Ornithological Literature to Document Long-Term Population Trends 总被引:1,自引:0,他引:1
Abstract: Unlike most North American blackbirds, Rusty Blackbirds ( Euphagus carolensis ) have shown steep population declines. Declines of approximately 90% are indicated for three recent decades from the Breeding Bird Survey, Christmas Bird Counts, and Quebec Checklist Program. Analyses of abundance classifications in bird distribution books and annotated checklists reveal an overlooked but long-term decline dating back to at least the early part of this century. Rusty Blackbirds were described as very common to abundant in 56% of the pre-1920 published accounts, 19% of the 1921–1950 accounts, and only 7% of the post-1950 accounts. Rusty Blackbirds were described as uncommon in none of the pre-1950 accounts, 18% of the 1951–1980 accounts, and 43% of the post-1980 accounts. A similar pattern was found for analyses based on local checklists. Destruction of wooded wetlands on wintering grounds, acid precipitation, and the conversion of boreal forest wetlands could have contributed to these declines. Systematic analysis of regional guides and checklists provides a valuable tool for examining large-scale and long-term population changes in birds. 相似文献
210.
Summary In a population of the splendid fairy-wren Malurus splendens, we describe 202 intrusions by solitary adult males in full breeding plumage into the territories of conspecifics. Intrusions were not secretive and although silent they involved conspicuous flight above the vegetation and several characteristic display elements, including petal-carrying. Fifteen intrusions were observed in the 2 months before eggs were laid, but the rest occurred during the period of nest-building and egg-laying when the breeding female was presumed to be fertile, and were by males from adjacent territories. A high level of extra-pair fertilization has previously been determined in this species and we interpret many of these intrusions as attempts by males to obtain extra-pair copulations (EPC); we call this activity philandering. The costs and benefits of EPC for males and females are discussed and the promiscuous mating strategy of M. splendens is contrasted with the persistent social pairing in stable groups of this long-lived cooperatively breeding species.Offprint requests to: I. Rowley 相似文献