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81.
生态系统调节水量的价值评估——兴山实例   总被引:8,自引:0,他引:8  
根据植被类型、坡度和土壤类型,分析了兴山县集水区内不同植被地块调节水量的能力。并且根据水能学的原理,分析了枯水期和洪峰期葛洲坝水电站的发电量与水流量的关系,建立了水流发电模拟模型。在上述分析的基础上,评估了兴山县境内生态系统调节香溪河等河流的水量,改善长江全年来水的均匀度,提高葛洲坝水电站发电效率的经济价值。  相似文献   
82.
模糊综合评价在脱硫技术优选中的应用   总被引:4,自引:0,他引:4  
基于模糊数学的基本原理,采用模糊矩阵和专家打分法(德尔菲法)相结合的方法,通过模糊综合评价来进行脱硫方案的优选。实例计算表明,此方法在脱硫技术优选中是可行的。  相似文献   
83.
Stream restoration is one of the most widely used interventions to mitigate urban stormwater impacts and improve water quality. Government agencies have typically focused urban stream restoration efforts on public lands that they already own, even though a substantial portion of stream miles in highly urbanized areas occur on privately owned land. Yet, limited research exists to distinguish household willingness to pay (WTP) for stream restoration occurring on private versus public land. In this study, we use a choice experiment to analyze how household WTP for stream restoration attributes vary by land ownership and distance to the restoration project. Our empirical results indicate that streambank stabilization approaches have positive WTP estimates that are substantially larger in magnitude than those related to riparian vegetation management for clearing or planting trees. In general, estimated total household WTP for each of the four restoration design scenarios on public land is higher than when the same restoration design is located on private land. Nonetheless, estimated household WTP for each restoration design scenario on private land is substantial, retaining the majority of the value found on public land in all cases.  相似文献   
84.
Air quality assessment by contingent valuation in Ji'nan, China   总被引:1,自引:0,他引:1  
Along with urbanization and environmental deterioration within China, many residents' desire for improved air quality has increased. To address this topic, this study focuses on the relationship between poor air quality and residents' willingness to pay for improved air quality in the city of Ji'nan. As a means of quantifying an individual's willingness to pay (WTP) for improved air quality, a contingent valuation method (CVM) was employed. A sample of 1500 residents was chosen, based on the stratified sampling method. The respondents' WTP was then elicited through a series of face-to-face interviews, conducted using a range of hypothetical, open-ended scenario questions. The results showed that 59.7% of respondents were able to express a positive WTP, and that the average WTP was 100 Chinese Yuan (CNY) per person, per year. In order to establish the relationship between endogenous variables and WTP, both a Probit model on the probability of a positive WTP, and a stepwise regression model were constructed. Most parameters in the econometric analysis demonstrated the expected results. It was found that annual household income, expenditure on the treatment of respiratory diseases and workers in the family significantly influenced WTP. The rates of positive WTP and the monetary amount were also larger for men than for women. Unlike developed countries, most respondents regard air quality improvement as a government responsibility in that more than 40% of respondents had no incentive to bear the costs of attempting to achieve better air quality, indicating a relatively low environmental consciousness.  相似文献   
85.
改善空气质量健康效益的非市场价值评估   总被引:1,自引:0,他引:1  
采用目前美国国家海洋局(NOAA)推荐的双边界二分式条件价值评估方法,对北京市空气质量改善产生的健康效益进行评估.对北京市城八区居民共发放880份调查问卷,调查居民对通过改善空气质量进而使健康免受危害计划的最大支付意愿.结果表明:未来5年内北京市居民每户的平均最大支付意愿为652.33元/a,居民健康总经济效益现值为61.08×108~75.41×108元;支付意愿影响因素分析表明,支付意愿与居民家庭经济状况、受教育程度、健康状况有正向关系,男性比女性的支付意愿高.分析结果与经济学原理相符,该评估的可靠性得以验证.   相似文献   
86.
Abstract: This study evaluates the economic value of riparian buffers and open space in a suburban watershed through two nonmarket valuation methods. A contingent valuation survey was implemented in the Dardenne Creek watershed, a suburban watershed of the St. Louis metropolitan area in Missouri, to evaluate the residents' perceptions of and willingness to pay (WTP) for adopting riparian buffers and preserving farmland in a hypothetical real estate market. A hedonic pricing model based on actual sale prices of homes in the watershed was applied to estimate the market value of open space and other environmental conditions such as flood zone and stream proximity in the study area. The results showed that residents' WTP was consistent with the economic values of open space and proximity to streams embedded in existing home prices. Through a better understanding of residents' perceptions and values, riparian buffer and open space programs can be designed and promoted to achieve greater implementation success and environmental benefit.  相似文献   
87.
基于CVM的荆州市稻田生态系统的景观休闲旅游价值评价   总被引:2,自引:0,他引:2  
采用条件价值评估法(Contingent Valuation Method,CVM)调查了荆州市居民对稻田生态系统景观休闲旅游功能的认知程度和支付意愿,对受访者的社会经济特征与支付意愿进行了相关性分析,并对荆州市稻田景观休闲旅游功能的价值进行了货币化评估。结果表明,居民对稻田景观休闲旅游功能的认知程度很低,对其十分了解的仅占3.5%,并且更侧重于旅游这一目的,达到61.1%。同时,78.7%的受访者认为稻田景观休闲旅游是赋有乡愁情感的。对影响受访者支付意愿的诸多因素进行相关性分析显示,稻田景观休闲旅游功能的支付意愿与受访者的文化程度(P=0.000)和月收入(P=0.004)呈极显著正相关。运用Logistic回归分析得出,文化程度对支付意愿的敏感性较大。按人均支付意愿计算,荆州市稻田生态系统景观休闲旅游的总价值约为4.43亿元  相似文献   
88.
文章以甘肃省玛曲县为例,通过对该县草地状况的分析,以玛曲县20世纪80年代草地状况作为过牧前状态,目前草地状况作为过牧后状态,探讨过牧对草地生态系统服务价值的影响,并通过对该县草地生态系统的分析,建立了过牧对草地生态系统服务价值影响评价指标体系,即食物生产、调节大气、营养物质循环与贮存、控制侵蚀、涵养水源、环境污染净化六大功能。最后运用生态经济学方法对过牧造成的经济损失进行了初步估算。结果表明,玛曲县由于过牧造成的直接和间接经济损失分别为:食物生产1.50×108元,调节大气1.04×109元,营养物质循环与贮存0.99×108元,控制侵蚀1.02×107元,涵养水源3.94×108元,环境污染净化2.9×107元,总经济损失达到1.72×109元,其中,间接经济损失占91.3%。  相似文献   
89.
论文以典型黄土高原丘陵沟壑区安塞县为例,运用市场价值法、替代工程法、影子价格法、机会成本法等方法对其境内7种不同类型农业生态系统的保持土壤(Es)、涵养水分(Ew)、固定CO2和释放O2(Ea)、维持营养物质循环(En)、净化环境(Ee)等服务功能进行了价值核算,初步估算出安塞县生态系统各服务功能的价值总量为3169870.46×104元,是其农林产品服务价值(Vp)的170倍。这一方面表明脆弱生态系统依然担当了重要的生态系统服务功能,为其经济生产力提供了巨大的生态服务。各种服务价值的大小依次为En(占89.85%)、Ew(占4.39%)、Ea(占4.18%)、Vp(占0.58%)、Es(占0.81%)、Ee(占0.18%)。另一方面也充分反映出在该地区“生态生产力”与“经济生产力”严重失衡。  相似文献   
90.
This paper contributes with an applied policy analysis of the predator preservation policy in Sweden. We estimate the overall mean willingness to pay (WTP) for preserving the four large predators in the Swedish fauna by applying the contingent valuation method. Using survey data from 2004 we find that 50 percent of the Swedish population is willing to contribute financially toward implementation of the predator policy package, and that the estimated overall mean WTP is approximately SEK 290. Further, we test for spatial differences in attitudes and WTP and find that respondents in Stockholm have the highest overall mean WTP, while respondents living in wolf-territories have the lowest. Our mean WTP measure is flawed with upward bias, since we cannot estimate the willingness to accept for those with clearly negative preferences regarding the predator policy package (e.g. hunters). In this paper, we set their WTP equal to zero. Thus, we cannot rule out the possibility that the mean willingness to pay is, in fact, negative, i.e. the social-value of implementing the predator policy is negative. Finally, the estimates of the overall WTP are sensitive to response-uncertainty. When the respondents indicate uncertainty about their valuation, they tend to state higher values.  相似文献   
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