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1.

In the UK for the period 1994-99, a broad range of environmental projects were given financial support through the European Agriculture Guidance and Guarantee Fund under the Objective 1 and Objective 5b programmes. This paper is concerned with the ex-post evaluation of these projects set within a Sustainable Development framework. The aim was to identify project types or characteristics that offered the greatest return on investment. A classification of six broad project types was adopted. The evaluation revealed that there were significant differences between individual projects with respect to the type and scale, and temporal and social distribution of the benefits they delivered. In particular, as well as delivering environmental and economic benefits, many projects made a significant contribution to the development of human and social capital. The paper concludes that it is possible to improve the basis for future project selection in order to maximise the returns on environmental investments in the context of sustainable development.  相似文献   

2.
This study employs a benefit-cost analysis framework to estimate market and non-market benefits and costs of controlling future spruce budworm (Choristoneura fumiferana) outbreaks on Crown forest lands in New Brunswick, Canada. We used: (i) an advanced timber supply model to project potential timber volume saved, timber value benefits, and costs of pest control efforts; and (ii) a recent contingent valuation method analysis that evaluated non-market benefits (i.e., changes in recreation opportunities and existence values) of controlling future spruce budworm outbreaks in the Province. A total of six alternative scenarios were evaluated, including two uncontrolled future budworm outbreak severities (moderate vs. severe) and, for each severity, three control program levels (protecting 10%, 20%, or 40% of the susceptible Crown land forest area). The economic criteria used to evaluate each scenario included benefit-cost ratios and net present values. Under severe outbreak conditions, results indicated that the highest benefit-cost ratio (4.04) occurred when protecting 10% (284,000 ha) of the susceptible area, and the highest net present value ($111 M) occurred when protecting 20% (568,000 ha) of the susceptible area. Under moderate outbreak conditions, the highest benefit-cost ratio (3.24) and net present value ($58.7 M) occurred when protecting 10% (284,000 ha) of the susceptible area. Inclusion of non-market values generally increased the benefit-cost ratios and net present values of the control programs, and in some cases, led to higher levels of control being supported. Results of this study highlight the importance of including non-market values into the decision making process of forest pest management.  相似文献   

3.
In the UK for the period 1994-99, a broad range of environmental projects were given financial support through the European Agriculture Guidance and Guarantee Fund under the Objective 1 and Objective 5b programmes. This paper is concerned with the ex-post evaluation of these projects set within a Sustainable Development framework. The aim was to identify project types or characteristics that offered the greatest return on investment. A classification of six broad project types was adopted. The evaluation revealed that there were significant differences between individual projects with respect to the type and scale, and temporal and social distribution of the benefits they delivered. In particular, as well as delivering environmental and economic benefits, many projects made a significant contribution to the development of human and social capital. The paper concludes that it is possible to improve the basis for future project selection in order to maximise the returns on environmental investments in the context of sustainable development.  相似文献   

4.
ABSTRACT: The main purpose of this study is to evaluate the management practice effects on Ming-Hu and Ming-Tan reservoir watersheds during the past 15 years. It is difficult to economically evaluate a watershed project consisting of a number of multisectoral and long term management practices and regulations. However, the reservoirs’ hydropower operations and their associated benefits and costs are highlighted in this study. The estimated management practice value (net present value) of 351 million NT (New Taiwan) dollars and a benefit-cost ratio of 1.189 are obtained for the Ming-Hu subwatershed. Because the Ming-Tan hydropower station only began commercial operation in 1992 the estimated management practice value is negative 103 million NT dollars (net present value) and the benefit-cost ratio is 0.653 in the Ming-Tan subwatershed. If the analysis period is contained to the year 2010, the benefit-cost ratio of Ming-Tan reservoir subwatershed becomes 1.103. Ming-Hu and Ming-Tan subwatersheds together share the benefit-cost ratio of 1.182 and the net present value of 1,589 million NT dollars. The results of the analyses indicate that the Taiwan Power Company, the watershed management agency, has implemented economically efficient watershed practices and regulations in Ming-Hu and Ming-Tan reservoir watersheds and the watershed management practices are worthwhile and should be sustained.  相似文献   

5.
6.
A 0.9 km-reach of Uvas Creek, California, was reconstructed as a sinuous, meandering channel in November 1995. In February 1996, this new channel washed out. We reviewed project documents to determine the basis for the project design and conducted our own historical geomorphological study to understand the processes operating in the catchment and project reach. The project was designed using a popular stream classification system, based on which the designers assumed that a "C4" channel (a meandering gravel-bed channel) would be stable at the site. Our historical geomorphological analysis showed that the reach had been braided historically, typical of streams draining the Franciscan Formation in the California Coast Ranges, with episodic flows and high sand and gravel transport. After the project washed out, Uvas Creek reestablished an irregular, braided sand-and-gravel channel, although the channel here was narrower than it had been historically, probably due to such factors as incision caused by gravel mining. Our study casts doubt on several assumptions common in many stream restoration projects: that channel stability is always an appropriate goal; that channel forms are determined by flows with return periods of about 1.5 years; that a channel classification system is an easy, appropriate basis for channel design; and that a new channel form can be imposed without addressing the processes that determine channel form.  相似文献   

7.
Densmore, Roseann V. and Kenneth F. Karle, 2009. Flood Effects on an Alaskan Stream Restoration Project: The Value of Long‐Term Monitoring. Journal of the American Water Resources Association (JAWRA) 45(6):1424‐1433. Abstract: On a nationwide basis, few stream restoration projects have long‐term programs in place to monitor the effects of floods on channel and floodplain configuration and floodplain vegetation, but long‐term and event‐based monitoring is required to measure the effects of these stochastic events and to use the knowledge for adaptive management and the design of future projects. This paper describes a long‐term monitoring effort (15 years) on a stream restoration project in Glen Creek in Denali National Park and Preserve in Alaska. The stream channel and floodplain of Glen Creek had been severely degraded over a period of 80 years by placer mining for gold, which left many reaches with unstable and incised streambeds without functioning vegetated floodplains. The objectives of the original project, initiated in 1991, were to develop and test methods for the hydraulic design of channel and floodplain morphology and for floodplain stabilization and riparian habitat recovery, and to conduct research and monitoring to provide information for future projects in similar degraded watersheds. Monitoring methods included surveyed stream cross‐sections, vegetation plots, and aerial, ground, and satellite photos. In this paper we address the immediate and outlying effects of a 25‐year flood on the stream and floodplain geometry and riparian vegetation. The long‐term monitoring revealed that significant channel widening occurred following the flood, likely caused by excessive upstream sediment loading and the fairly slow development of floodplain vegetation in this climate. Our results illustrated design flaws, particularly in regard to identification and analysis of sediment sources and the dominant processes of channel adjustment.  相似文献   

8.
ABSTRACT: For many years, Federal water resources projects have been subjected to benefit-cost analysis to establish their economic feasibility. Several years ago social well-being was added as a consideration. This paper discusses the state-of-the-art in analyzing and evaluating aspects of social well-being. It stresses current short-falls and advocates a direction for further efforts.  相似文献   

9.

The first annual Sustainable Community competition, co-sponsored by the Federation of Canadian Municipalities (FCM) and CH2M Hill in 2000, received 52 submissions from municipalities across Canada. These submissions were systematically analysed to identify common characteristics shared by competition entrants, including what differentiates competition participants from other Canadian municipalities, what kinds of sustainability projecs municipalities have been most likely to undertake and what motivating and success factors are most commonly cited. Urban municipalities were more likely than rural municipalities to undertake sustainability projects. Stakeholder involvement was found to be the most important factor in determining the success of a project. Many projects in the competition had not identified clear holistic visions and benchmarks, and these were noted as areas where improvement could be made. The impact of higher levels of government in setting benchmarks and providing support was also noteworthy.  相似文献   

10.
Incorporating environmental and natural resource impacts into the benefit-cost analysis of projects in the developing world now relies on a solid body of theory and recommended techniques, but there remain concerns with how this is done in practice. One aspect arises when time and resource constraints make highly sophisticated analysis difficult or impossible. This paper discusses situations where analyses can be improved using relatively simple ‘short cut’ techniques that substitute for more formal analysis that cannot be undertaken realistically or provide an added perspective on project viability. Case studies are employed to illustrate the techniques, based upon the author's experience with appraisals at the World Bank, Food and Agriculture Organization (FAO) and the International Fund for Agricultural Development (IFAD). It is shown that short cut techniques can dramatically alter the outcome of an appraisal at relatively little cost. However, caution is advised since such techniques can be misused, so that the development of suitable protocols is desirable.  相似文献   

11.
ABSTRACT: Land use and surface water data for nitrogen and pesticides (1995 to 1997) are reported for the Walnut Creek Watershed Monitoring Project, Jasper County Iowa. The Walnut Creek project was established in 1995 as a nonpoint source monitoring program in relation to watershed habitat restoration and agricultural management changes implemented at the Neal Smith National Wildlife Refuge by the U.S. Fish and Wildlife Service. The monitoring project utilizes a paired‐watershed approach (Walnut and Squaw creeks) as well as upstream/downstream comparisons on Walnut for analysis and tracking of trends. From 1992 to 1997, 13.4 percent of the watershed was converted from row crop to native prairie in the Walnut Creek watershed. Including another 6 percent of watershed farmed on a cash‐rent basis, land use changes have been implemented on 19.4 percent of the watershed by the USFWS. Nitrogen and pesticide applications were reduced an estimated 18 percent and 28 percent in the watershed from land use changes. Atrazine was detected most often in surface water with frequencies of detection ranging from 76–86 percent. No significant differences were noted in atrazine concentrations between Walnut and Squaw Creek. Nitrate‐N concentrations measured in both watersheds were similar; both basins showed a similar pattern of detection and an overall reduction in nitrate‐N concentrations from upstream to downstream monitoring sites. Water quality improvements are suggested by nitrate‐N and chloride ratios less than one in the Walnut Creek watershed and low nitrate‐N concentrations measured in the subbasin of Walnut Creek containing the greatest amount of land use changes. Atrazine and nitrate‐N concentrations from the lower portion of the Walnut Creek watershed (including the prairie restoration area) may be decreasing in relation to the upstream untreated component of the watershed. The frequencies of pesticide detections and mean nitrate‐N concentrations appear related to the percentage of row crop in the basins and subbasins. Although some results are encouraging, definitive water quality improvements have not been observed during the first three years of monitoring. Possible reasons include: (1) more time is needed to adequately detect changes; (2) the size of the watershed is too large to detect improvements; (3) land use changes are not located in the area of the watershed where they would have greatest effect; or (4) water quality improvements have occurred but have been missed by the project monitoring design. Longer‐term monitoring will allow better evaluation of the impact of restoration activities on water quality.  相似文献   

12.
This article reviews the application of environmental impact assessment (EIA) procedures and practices to three watershed modification projects situaled in western Canada. These ventures were justified for accelerating regional economic development, and cover the period during which public concerns for protecting the environment rapidly made their way into the national political agenda. An historical account and analysis of the situation, therefore, seems desirable in order to understand the development of EIA processes, practices, and methodologies since the start of construction of the first project in 1961. This study concludes that there has been good progress in predicting and evaluating environmental and related social impacts of watershed modification proposals. However, a number of obstacles need to be overcome before EIA can firmly establish itself as an effective planning tool. These difficulties include jurisdictional confusions and conflicts, division of authority and responsibility in designing and implementing appropriate mitigative and monitoring measures, lack of tested EIA methodologies, and limited availability of qualified human resources. A number of conclusions and suggestions are offered so that future watershed modification proposals may be planned and implemented in a more environmentally sustainable fashion. These include: (1) EIA processes must be completed before irrevocable decisions are made. (2) Any major intrusion into a watershed is likely to impact on some major components of the ecosystem(s). (3) Mitigation costs must form part of the benefit-cost analysis of any project proposal. (4) Interjurisdictional cooperation is imperative where watersheds cross political boundaries. (5) The EIA process is a public process, hence public concerns must be dealt with fairly. (6) The role of science in the EIA process must be at arms length from project proponents and regulators, and allowed to function in the interest of the protection of the environment and public health and safety. The views expressed here are the authors’ own and do not necessarily reflect those of FEARO and/or other government agencies and officials involved in the review of these projects.  相似文献   

13.
The first annual Sustainable Community competition, co-sponsored by the Federation of Canadian Municipalities (FCM) and CH2M Hill in 2000, received 52 submissions from municipalities across Canada. These submissions were systematically analysed to identify common characteristics shared by competition entrants, including what differentiates competition participants from other Canadian municipalities, what kinds of sustainability projecs municipalities have been most likely to undertake and what motivating and success factors are most commonly cited. Urban municipalities were more likely than rural municipalities to undertake sustainability projects. Stakeholder involvement was found to be the most important factor in determining the success of a project. Many projects in the competition had not identified clear holistic visions and benchmarks, and these were noted as areas where improvement could be made. The impact of higher levels of government in setting benchmarks and providing support was also noteworthy.  相似文献   

14.
ABSTRACT: Various techniques, one of which is zoning, are used to control the extent of flood damage. The benefit-cost analysis of zoning programs must take into account the random nature of flooding. This paper outlines a method for determining not only the expected value of the benefit-cost ratio, but also the probability of such a zoning program being profitable. It also presents an application of the method to the assessment of the Outaouais Regional Community zoning program.  相似文献   

15.
ABSTRACT: We compared the recovery from abusive grazing of aquatic habitat due to different range management on two geomorphically similar rangeland streams in northwest Nevada. Managers excluded livestock from the Mahogany Creek watershed from 1976 to 1990 while allowing rotation of rest grazing on its tributary Summer Camp Creek. Bank stability, defined as the lack of apparent bank erosion or deposition, improved through the study period on both streams, but periodic grazing and flooding decreased stability more on Summer Camp Creek than flooding alone on Mahogany Creek. Pool quantity and quality on each stream decreased because of coarse woody debris removal and sediment deposition during a drought. Fine stream bottom sediments decreased five years after the removal of livestock, but sedimentation increased during low flows in both streams below road crossings. Tree cover increased 35 percent at both streams. Thus, recovery of stability and cover and decreased sedimentation are compatible with rotation of rest grazing on Summer Camp Creek. Width/depth ratio and gravel/cobble percent did not change because they are inherently stable in this stream type. Management activities such as coarse woody debris removal limited pool recover and road crossings increased sedimentation.  相似文献   

16.
A ground water development project in the northern part of Thailand was appraised by means of benefit-cost analysis. This is the first project in Thailand to develop ground water for irrigation purposes and it is also the first project which made use of an underground PVC pipe water distribution system. Results indicate that the project is economically feasible. In comparing different water distribution systems, it is also found that distribution by means of underground PVC pipes is more economical compared to an open ditch system if the life of the latter is relatively short and the rates of inflation are high.  相似文献   

17.
Ice, George G., George W. Brown, John A. Gravelle, C. Rhett Jackson, Jeffrey T. Light, Timothy E. Link, Douglas J. Martin, Dale J. McGreer, and Arne E. Skaugset, 2010. Discussion –“Stream Temperature Relationships to Forest Harvest in Western Washington” by Michael M. Pollock, Timothy J. Beechie, Martin Liermann, and Richard E. Bigley. Journal of the American Water Resources Association (JAWRA) 46(4): 838-842. DOI: 10.1111/j.1752-1688.2010.00441.x  相似文献   

18.
Schilling, Keith E., Thomas M. Isenhart, Jason A. Palmer, Calvin F. Wolter, and Jean Spooner, 2011. Impacts of Land‐Cover Change on Suspended Sediment Transport in Two Agricultural Watersheds. Journal of the American Water Resources Association (JAWRA) 47(4):672‐686. DOI: 10.1111/j.1752‐1688.2011.00533.x Abstract: Suspended sediment is a major water quality problem, yet few monitoring studies have been of sufficient scale and duration to assess the effectiveness of land‐use change or conservation practice implementation at a watershed scale. Daily discharge and suspended sediment export from two 5,000‐ha watersheds in central Iowa were monitored over a 10‐year period (water years 1996‐2005). In Walnut Creek watershed, a large portion of land was converted from row crop to native prairie, whereas in Squaw Creek land use remained predominantly row crop agriculture. Suspended sediment loads were similar in both watersheds, exhibiting flashy behavior typical of incised channels. Modeling suggested that expected total soil erosion in Walnut Creek should have been reduced 46% relative to Squaw Creek due to changes in land use, yet measured suspended sediment loads showed no significant differences. Stream mapping indicated that Walnut Creek had three times more eroding streambank lengths than did Squaw Creek suggesting that streambank erosion dominated sediment sources in Walnut Creek and sheet and rill sources dominated sediment sources in Squaw Creek. Our results demonstrate that an accounting of all sources of sediment erosion and delivery is needed to characterize sediment reductions in watershed projects combined with long‐term, intensive monitoring and modeling to account for possible lag times in the manifestation of the benefits of conservation practices on water quality.  相似文献   

19.
Rehabilitation of river ecosystems is generally initiated when a river is no longer able to provide benefits to humans and other living beings. The major purposes of river rehabilitation projects are improving water quality, conserving nature, rehabilitating fisheries and riparian habitats, flood mitigation, and creating recreational opportunities. For a river rehabilitation project to be successful, it must have specific and clearly explained objectives, although these objectives will vary for each project depending upon factors such as economics, public demand, ecosystem benefits, and the like. In this article, we provide a critical analysis of the purposes that drive river rehabilitation projects and we identify and discuss impediments that can cause a project to deviate from its intended goals. We also discuss major constraints on rehabilitation efforts that can result in failed projects.  相似文献   

20.
This paper analyses the relationship between social rates of discount to be used in benefit-cost analysis of investment projects and optimal intertemporal plans of capital accumulation and resource depletion. The discussion is conducted in the context of models that incorporate exhaustible natural resources. It is argued that discount rates are a derived concept and that they ought to be arrived at from a consideration of our sense of intergenerational justice and optimal programmes arrived at from intergenerational welfare criteria.  相似文献   

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