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1.
This paper describes an approach to account for asymmetric preference formation in discrete choice models used for environmental valuation. The paper draws on data from a case study on preferences for environmental change resulting from a hypothetical rural development and conservation programme in Indonesia. Local knowledge on the current state of the environment was used to define an individual-specific status quo that consistently frames changes in a range of environmental services as gains or losses matching the perceptions of the local population living in the vicinity of a National Park. I estimated choice models that included separate parameters for increases and decreases in attribute levels for the environmental services and derived the indicators of local willingness to pay (WTP) corresponding to the bidirectional changes relative to the individual-specific status quo option. I found clear evidence of an asymmetric response to increase and decrease in attribute levels relative to the status quo. Ignoring asymmetric preference formation can therefore result in biased estimates of WTP indicators and welfare measures of change in cases where the outcomes of environmental programmes can plausibly result in both an increase and a decrease relative to a reference option. Compared to a symmetrical modelling approach, the combination of simultaneously accounting for asymmetric preference formation and preference heterogeneity in the choice model yielded additional insights that may be used to inform the development of local strategies towards biodiversity conservation.  相似文献   

2.
A distinction is drawn between opportunity cost and willingness‐to‐pay (WTP) valuations of the environment and the latter are shown to be appropriate only in situations where no agreed environmental standards exist. WTP measures of environmental effects form the basis of the Pigovian model of externalities. This model is applicable where individuals directly perceive environmental effects as nuisances or the reverse. But with many environmental problems direct perception does not occur and the Pigovian model is not applicable. In these circumstances it is wrong to talk of biases in WTP estimations since no ‘true’ WTP exists. A decision rule grounded in WTP could still be used but is open to serious objections. The preferred approach is through the development of environmental standards.  相似文献   

3.
Beach protection has become a major issue in reducing coastal risks (erosion and flooding). It is thus advisable to study residents’ preferences for mitigation strategies. Willingness-to-pay (WTP) by permanent and secondary residents for flood protection provided to properties by Languedoc-Roussillon beaches (French Mediterranean coast) is investigated by a contingent valuation study. Results show that WTP is more influenced by risk perception variables than by socio-economic ones. The WTP is then extrapolated on the basis of different adaptation strategies (laissez-faire, managed retreat, denial etc.) which provided information about expected damage associated with sea level rise at the 2100 time horizon.  相似文献   

4.
The Yellow River has been intensively affected by human activities, particularly in the past 50 years, including soil–water conservation in the upper and middle drainage basin, flood protection in the lower reaches, and flow regulation and water diversion in the whole drainage basin. All these changes may impact sedimentation process of the lower Yellow River in different ways. Assessing these impacts comprehensively is important for more effective environmental management of the drainage basin. Based on the data of annual river flow, sediment load, and channel sedimentation in the lower Yellow River between 1950 and 1997, the purpose of this paper is to analyze the overall trend of channel sedimentation rate at a time scale of 50 years, and its formative cause. It was found in this study that erosion control measures and water diversion have counteractive impacts on sedimentation rate in the lower Yellow River. Although both annual river flow and sediment decreased, there was no change in channel sedimentation rate. A regression analysis indicated that the sedimentation in the lower Yellow River decreased with the sediment input to the lower Yellow River but increased with the river flow input. In the past 30–40 years, the basin-wide practice of erosion and sediment control measures resulted in a decline in sediment supply to the Yellow River; at the same time, the human development of water resources that required river flow regulation and water diversion caused great reduction in river flow. The former may reduce the sedimentation in the lower Yellow River, but the reduction of river flow increased the sedimentation. When their effects counterbalanced each other, the overall trend of channel sedimentation in the lower Yellow River remained unchanged. This fact may help us to better understand the positive and negative effects of human activities in the Yellow River basin and to pay more attention to the negative effect of the development of water resources. The results of this study demonstrate that, if the overuse of river water cannot be controlled, the reduction of channel sedimentation in the lower Yellow River cannot be realized through the practice of erosion and sediment control measures.  相似文献   

5.
Geomorphologically appropriate rehabilitation measures were proposed to enhance the in-stream environment of the lowland River Idle, north Nottinghamshire, UK. However, the River Idle has multi-functional management requirements including those of flood defence so environmental enhancement must be pursued without significantly increasing the flood risk. Hydraulic testing of rehabilitation proposals is complicated because of the stringent assumptions about flow and morphology in ‘traditional’ hydraulic models. While new generation two- and three-dimension hydraulic models may overcome some of these problems, they are extremely data intensive, require advanced modelling capabilities and are, therefore, very expensive to apply. Also, they do not yet predict morphology-flow interactions adequately. As an alternative, several simple hydraulic models were applied to test the rehabilitation proposals, based on a fitness-for-purpose criterion.BENDFLOW was applied to fine tune the optimal siting of measures and to estimate the additional near-bank scour generated by proposed bend re-profiling. HMODEL2 and the FCFA method were used to test the impact on local channel conveyance capacities and HECRAS was applied to simulate the impact of the proposals on regional flood defence. Indicative results from the testing suggested a maximum increase in near-bank scour of 0·15 m in re-profiled bends, a loss of approximately 10% in flood conveyance locally due to deflector installation or reed and tree planting, and a 0·12 m increase in flood stage within the reach for a 15 year flood. The modelling results were acceptable to the management authority as an indication of an acceptable compromise between flood defence and conservation interests, and construction of the measures followed in 1996. It is clearly that it will require the results of post-project monitoring to indicate whether compromises made to the rehabilitation initiatives in order to satisfy flood defence requirements have unduly reduced their environmental enhancement potential but, for assessing the proposed methods, the models are recommended for use other lowland river environments.  相似文献   

6.
Knowledge of socio-demographic factors affecting attitudes to and perception of risk is an important instrument in enhancing efficiencies of interventions. The authors evaluated whether socio-demographic variables affected attitudes to an environmental issue (securing future drinking water). An important aspect was the delay between time of environmental pollution and time of human exposure and thereby potential health risk. Gender, education, place of residence and age all influenced the extent to which individuals were willing to allocate present resources to alleviate a future problem. Specifically, people above the age of 50 appeared more reluctant to pay for an intervention against a future potential health threat. The authors found a significant correlation between attitude and willingness to pay (WTP). In the authors' scenarios, the WTP variable worked more as a dichotomous variable than as a continuous variable, stressing the importance and relevance of the WTP=0 answers.  相似文献   

7.
Vulnerability of river channels to urbanization has been lessened by the extensive construction of artificial water control improvements. The challenge, however, is that traditional engineering practices on isolated parts of a river may disturb the hydrologic continuity and interrupt the natural state of ecosystems. Taking the Xiaoqinghe River basin as a whole, we developed a river channel network design to mitigate river risks while sustaining the river in a state as natural as possible. The river channel risk from drought during low-flow periods and flood during high-flow periods as well as the potential for water diversion were articulated in detail. On the basis of the above investigation, a network with “nodes” and “edges” could be designed to relieve drought hazard and flood risk respectively. Subsequently, the shortest path algorithm in the graph theory was applied to optimize the low-flow network by searching for the shortest path. The effectiveness assessment was then performed for the low-flow and high-flow networks, respectively. For the former, the network connectedness was evaluated by calculating the “gamma index of connectivity” and “alpha index of circuitry”; for the latter, the ratio of flood-control capacity to projected flood level was devised and calculated. Results show that the design boosted network connectivity and circuitry during the low-flow periods, indicating a more fluent flow pathway, and reduced the flood risk during the high-flow periods.  相似文献   

8.
Household Demand for Waste Recycling Services   总被引:1,自引:0,他引:1  
Municipalities everywhere are coping with increasing amounts of solid waste and need urgently to formulate efficient and sustainable solutions to the problem. This study examines the use of economic incentives in municipal waste management. Specifically, we address the issue of recycling, if and when this waste management option is—on social welfare grounds—a preferred solution.A number of studies have recently assessed the monetary value of the externalities of alternative solid waste management options. In the present context, these subsidies could be interpreted as the implicit value of the benefits from reducing environmental externalities associated with landfilling as perceived by local government authorities. We surmise that the difference between mean households willingness to pay (WTP) for recycling services, via the purchase of a subsidized waste disposal facility, and the above (proxy) value of externalities reflects the difference between private and public perception regarding the negative externality associated with landfilling. We believe that this information is useful in determining the level of subsidization needed (if at all) to sustain any recycling program.The study is unique in the sense that its conclusions are based on revealed household behavior when faced with increased disposal costs, as well as information on WTP responses in hypothetical but related (and, therefore, familiar) scenarios. The article also explores the influence of the subsidization schemes on recycling rates. It was found that with low levels of effort needed to participate in a curbside recycling program, households participation rates are mainly influenced by economic variables and age, and households are willing to pay a higher price for the recycling scheme. When the required effort level is relatively high, however, households would pay a lower price, and the rate is influenced mainly by their environmental commitment and by economic considerations. We found that in both cases a subsidy would be required in order to achieve an efficient level of recycling. The median price that households are willing to pay for recycling devices is found to be about NIS 370 (New Israeli Shekel, approximately $90).  相似文献   

9.
Abstract

Electric vehicles (EVs) are currently being discussed as a promising means to increase the energy efficiency and sustainability of today's transport systems. While technological progress and cost reduction are certainly crucial topics for their successful diffusion, consumer acceptance is another issue that warrants further analysis. Based on a large online survey (N?=?969), we compared four consumer groups which differ in their likelihood to purchase an EV with regard to their socio-demographic characteristics, their willingness to pay (WTP) and their perceptions of EVs. The findings indicate that early users in Germany are most likely to be middle-aged men living with their families in a multi-vehicle household who have a higher WTP for an EV. Perceived compatibility of an EV with personal needs seems to be the most influential factor on the stated willingness to purchase an EV. With regard to the promotion of EVs, strengthening their environmental advantages and providing financial incentives for purchase are rated as important measures by a majority of the sample, while performance characteristics which are comparable to conventional vehicles seem to be less important for most participants. Based on the data analyses, we provide recommendations for measures regarding the further development and promotion of EVs.  相似文献   

10.
洞庭湖土地利用/覆被变化及洪涝灾害研究进展   总被引:1,自引:0,他引:1  
王亚梅  李忠武  曾光明 《四川环境》2009,28(5):62-66,74
洞庭湖是长江流域重要的调蓄滞洪区、物种基因库和商品粮基地,具有重要的战略地位。然而由于人类不合理的开发利用致使湖泊功能和效益不断下降。系统认识洞庭湖自然、社会经济属性,揭示其内在的演变规律,有助于洞庭湖区资源的合理配置、环境保护和经济的可持续发展。本文从土地利用/覆被变化、洪涝灾害等方面,综述了洞庭湖的研究进展。研究结果表明目前对洞庭湖研究的深度和广度均不够,洞庭湖作为通江湖泊的复杂性和不确定性、研究思路方法创新意识不够、基础数据难以获得、洞庭湖区血吸虫病害严重等是洞庭湖研究难以深入的主要原因。最后从洞庭湖流域土地利用/覆被变化及其水文效应与调控研究、洞庭湖区洪灾风险评价与区划研究两个方面展望了今后研究的重点。  相似文献   

11.
This article investigated public preferences for forest biomass based liquid biofuels, particularly ethanol blends of 10% (E10) and 85% (E85). We conducted a choice experiment study in three southern states in the United States: Arkansas, Florida, and Virginia. Reducing atmospheric CO2, decreasing risk of wildfires and pest outbreaks, and enhancing biodiversity were presented to respondents as attributes of using biofuels. Results indicated that individuals had a positive extra willingness to pay (WTP) for both ethanol blends. The extra WTP was greater for higher blends that offered larger environment benefits. The WTPs for E10 were $0.56 gallon?1, $0.58 gallon?1, and $0.48 gallon?1, and for E85 they were $0.82 gallon?1, $1.17 gallon?1, and $1.06 gallon?1 in Arkansas, Florida, and Virginia, respectively. Although differences in WTP for E10 were statistically insignificant among the three states, significant differences were found in the WTP for E85 between AR and FL and between AR and VA. Preferences for the environmental attributes appeared to be heterogeneous, as respondents’ were willing to pay a premium for E10 in all three states to facilitate the reduction of CO2 and the improvement of biodiversity but were not willing to pay more for E85 in order to enhance biodiversity.  相似文献   

12.
In this paper the contingent valuation method (CVM) is applied to public risk reduction. Theory suggests that the size of the stated willingness to pay (WTP) for risk reduction depends on private activities aimed at reducing the risk level for the individual. The empirical results suggest that considering private averting activities increases the explanatory power of the estimated WTP function significantly. Thus, WTP passes the scope test which proposes that larger reductions from a larger baseline risk should be valued higher than lower risk reductions from a lower baseline risk. Furthermore, we demonstrate that the follow-up response format induces anchoring effects.  相似文献   

13.
Air pollution, a by-product of economic growth, has been incurring extensive environmental costs in Seoul, Korea. Unfortunately, air pollution impacts are not treated as a commercial item, and thus it is difficult to measure the environmental costs arising from air pollution. There is an imminent need to find a way to measure air pollution impacts so that appropriate actions can be taken to control air pollution. Therefore, this study attempts to apply a choice experiment to quantifying the environmental costs of four air pollution impacts (mortality, morbidity, soiling damage, and poor visibility), using a specific case study of Seoul. We consider the trade-offs between price and attributes of air pollution impacts for selecting a preferred alternative and derive the marginal willingness to pay (WTP) estimate for each attribute. According to the results, the households' monthly WTP for a 10% reduction in the concentrations of major pollutants in Seoul was found to be approximately 5494 Korean won (USD 4.6) and the total annual WTP for the entire population of Seoul was about 203.4 billion Korean won (USD 169.5 million). This study is expected to provide policy-makers with useful information for evaluating and planning environmental policies relating specifically to air pollution.  相似文献   

14.
Summary In order to determine the environmental problems as perceived by the community of Luján (Province of Buenos Aires, Argentina), a survey was carried out. The relationship between environmental perception and socio-economic level was also studied. The most important problems reported by the community were the floods, which occur when the Luján river overflows its banks, and the contamination of this river as it flows through Luján city. Deficiencies in the tourist infrastructure were also considered to be serious. The least perceived problem was that of industrial air pollution. Positive correlations between environmental perception, socio-economic standing and levels of instruction were observed.Claudia Feijoó is a Lecturer in Ecology at the National University of Luján. Her research interests are in environmental perception and ecology of rivers and polluted waters. Prof. Fernando Momo is Professor of Ecology at the same University. His research interests are focused on theoretical ecology and ecological modelling, especially as applied to aquatic ecology.  相似文献   

15.
This paper presents the findings of two 'green pricing' studies conducted to evaluate public support of utilities' investments in renewable energy technologies. These studies compared hypothetical WTP statements with actual payment commitments. The results of these studies indicate that the CVM can be an accurate indicator of an individual's WTP, but that it is an unreliable predictor of which individuals will actually pay. This has important implications for aggregating mean WTP estimates of the value of environmental benefits. It also suggests that market simulations can be useful for predicting programme participation rates when voluntary donations are used as a payment vehicle.  相似文献   

16.
Public preferences for conservation and environmental management may be identified in willingness to pay (WTP) studies. Normally part of a contingent valuation exercise, WTP studies elicit monetary estimates of non-market economic goods. This paper describes a new approach to WTP, the CV Market Stall, a technique that adds a discursive, qualitative dimension to contingent valuation. It is suggested that the CV Market Stall technique is a good method for exploring attitudes and responses to environmental project proposals. The flexible format, with an emphasis upon information provision, discussion and learning would also allow contingent valuation to be extended to much more complex and uncertain environmental issues.  相似文献   

17.
This article reports a study of the public perception of large wood in rivers and streams in the United States. Large wood is an element of freshwater aquatic ecosystems that has attracted much scientific interest in recent years because of its value in biological and geomorphological processes. At the heart of the issue is the nature of the relationship between scientific recognition of the ecological and geomorphological benefits of wood in rivers, management practices utilizing wood for river remediation progress, and public perceptions of in-channel wood. Surveys of students’ perceptions of riverscapes with and without large wood in the states of Colorado, Connecticut, Georgia, Illinois, Iowa, Missouri, Oregon, and Texas suggest that many individuals in the United States adhere to traditionally negative views of wood. Except for students in Oregon, most respondents considered photographs of riverscapes with wood to be less aesthetically pleasing and needing more improvement than rivers without wood. Analysis of reasons given for improvement needs suggest that Oregon students are concerned with improving channels without wood for fauna habitat, whereas respondents elsewhere focused on the need for cleaning wood-rich channels for flood risk management. These results underscore the importance of public education to increase awareness of the geomorphological and ecological significance of wood in stream systems. This awareness should foster more positive attitudes toward wood. An integrated program of research, education, and policy is advocated to bridge the gap between scientific knowledge and public perception for effective management and restoration of river systems with wood.  相似文献   

18.
Floodplain soils along the river Rhine in the Netherlands show a large spatial variability in pollutant concentrations. For an accurate ecological risk characterization of the river floodplains, this heterogeneity has to be included into the ecological risk assessment. In this paper a procedure is presented that incorporates spatial components of exposure into the risk assessment by linking geographical information systems (GIS) with models that estimate exposure for the most sensitive species of a floodplain. The procedure uses readily available site-specific data and is applicable to a wide range of locations and floodplain management scenarios. The procedure is applied to estimate exposure risks to metals for a typical foodweb in the Afferdensche and Deestsche Waarden floodplain along the river Waal, the main branch of the Rhine in the Netherlands. Spatial variability of pollutants is quantified by overlaying appropriate topographic and soil maps resulting in the definition of homogeneous pollution units. Next to that, GIS is used to include foraging behavior of the exposed terrestrial organisms. Risk estimates from a probabilistic exposure model were used to construct site-specific risk maps for the floodplain. Based on these maps, recommendations for future management of the floodplain can be made that aim at both ecological rehabilitation and an optimal flood defense.  相似文献   

19.
Arid zone rivers have highly variable flow rates, and flood control projects are needed to protect adjacent property from flood damage. On the other hand, riparian corridors provide important wildlife habitat, especially for birds, and riparian vegetation is adapted to the natural variability in flows on these rivers. While environmental and flood control goals might appear to be at odds, we show that both goals can be accommodated in the Limitrophe Region (the shared border between the United States and Mexico) on the Lower Colorado River. In 1999, the International Boundary and Water Commission proposed a routine maintenance project to clear vegetation and create a pilot channel within the Limitrophe Region to improve flow capacity and delineate the border. In 2000, however, Minute 306 to the international water treaty was adopted, which calls for consideration of environmental effects of IBWC actions. We conducted vegetation and bird surveys within the Limitrophe and found that this river segment is unusually rich in native cottonwood and willow trees, marsh habitat, and resident and migratory birds compared to flow-regulated segments of river. A flood-frequency analysis showed that the existing levee system can easily contain a 100 year flood even if vegetation is not removed, and the existing braided channel system has greater carrying capacity than the proposed pilot channel.  相似文献   

20.
Environmental planners often propose tourism as a means of financing programmes to protect significant environmental areas. Surveys of tourists can provide useful information about the significance of environmental problems, trade-offs among policy objectives, willingness to pay (WTP) for protection programmes and preferences for different payment mechanisms. In Khanh Hoa Province, the provincial People's Committee, the Ministry of Fisheries and the World Conservation Union are working to implement Viet Nam's first marine protected area (MPA) in Nha Trang Bay. This paper reports the results of a survey of local and other Vietnamese and foreign tourists to islands that will be included in the MPA. The majority of respondents thought rubbish on the beaches, water pollution and vendors on beaches were problems and that the MPA was a good idea. Foreign tourists were significantly more likely to perceive environmental problems than were Vietnamese tourists, and persons who agreed there were environmental problems were significantly more likely to support the concept of an MPA, despite the potential for possible economic effects with distributive consequences. WTP for protection was modest and positively correlated with education and income. Although foreign tourists were on average willing to pay more, a larger proportion of Vietnamese tourists were willing to pay some amount to support the MPA. Analyses indicate that changes in income and education expected with economic development will increase both awareness of problems and WTP for protection. The results of this analysis are both encouraging and cautionary. The need for an MPA is clearly recognized by most tourists, and most tourists are willing to pay small fees to support the MPA. Given that education has significant impacts on both perceptions of problems and WTP, educational programmes may be an effective strategy for managing the competing objectives of protection and use.  相似文献   

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