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61.
Beach erosion can have major economic implications because of the potential impact on coastal recreation demand – particularly for countries where coastal tourism is one of the main sources of external revenue. Djerba Island (Tunisia) falls in that category. With about 125 km of coastline, Djerba Island is one of the most important Tunisian destinations. However, the island is experiencing coastal erosion problems. The Tunisia government launched a project to fight costal erosion through the Stabiplage technique. This study provides the first economic valuation of beach erosion control in Tunisia and is the first one that focuses on the Stabiplage technique. Specifically, a contingent valuation survey is carried out to elicit the public willingness to pay (WTP) for the project. An interval payment card question format is used to obtain information about WTP from representative samples of residents and tourists in Djerba. The results reveal a positive WTP for the project. Aggregate WTP estimates range from €133,459 (median value) to €5,180,269 (mean value). These values can help inform decisions about whether to undertake the project based on either the benefit-cost ratio rule or majority voting rule.  相似文献   
62.
As natural ecosystems provide the material basis and fundamental support for regional sustainable devel-opment,the sustainability of natural ecosystems is an important prerequisite and a viable approach for the achievement of regional sustainable development.It is also the final criteria to assess whether sustainable development paradigm is successful.Along with the increasing impacts of human activities on natural ecosystems,the evaluation of regional ecological sustainability has become one of the key issues for research on macro ecology and sustainable development.Based on different unit of indicators,this study firstly groups the evaluation frameworks of regional ecological sus-tainability into three major types:comprehensive index evaluation with dimensionless unit,monetary valuation,and biophysical quantity measurement.We then discuss and compare these types in terms of basic principles,scope of ap-plications,advantages and shortcomings.Finally,drawn on the discussion about characteristics of ecological sustain-ability,we outline the current trend and future directions of regional ecological sustainability evaluation,for instance,transition from sustainable development evaluation to sustainability science,integration of goal-oriented and problem-solving approaches,combination of spatial pattern analysis and ecological sustainability evaluation,and en-hancement of ecological sustainability evaluation at landscape scale.  相似文献   
63.
Coastal wetlands provide a range of valuable ecosystem services, including protecting coastal communities from storms. We estimated for the first time the global value of these storm protection services for all coastal wetlands for both damages avoided and lives saved. We used the historical tracks of 1,014 tropical cyclones since 1902 that recorded property damage and/or human casualties in 71 countries/regions. We used Bayesian and OLS statistical techniques to relate storm damages and lives lost to: wind speed, storm forward speed, the year of the storm, the volume of ocean water proximal to landfall, and GDP, population, and coastal wetlands in the swath of the storm. Based on current storm probabilities, we estimate the median annual global value of coastal wetlands for storm protection at $447 billion/yr (2015$US) ($213 - $837 billion/yr, 90% CI) and 4,620 lives saved per year (3,320 – 6,550, 90% CI). The 40 million hectares of coastal wetlands in storm prone areas provided an average of $11,000/ha/yr in avoided storm damages. The frequency and intensity of tropical cyclones has been increasing in recent decades and is projected to further increase with climate change. Consequently, the already significant benefits from protecting and restoring coastal wetlands will become increasingly important and valuable in the future. These results justify much larger investments in conservation and restoration of coastal wetlands.  相似文献   
64.
针对当前房产税征收对信息化及房产批量评估的需求,该文提出了融合GIS和VIKOR方法的房产批量评估模型。结合GIS技术和熵权法解决了房产价格影响因子量化过程中的主观性问题,提高了房产价格影响因子量化的准确性和量化效率;采用VIKOR方法克服了常用智能算法存在较强样本数据依赖的问题,使得估价结果更为可靠。基于该模型开发的系统对赣州市具有代表性的5处待估房产估价,结果表明:估算出的房产价格与实际成交价格接近,表明该模型具有较高准确性。  相似文献   
65.
Coral reefs provide a multitude of goods and services, some of which are difficult to value due to their intangible nature and the absence of markets to ascribe their relative worth. The coral reefs of Sodwana Bay on the northeast coast of South Africa provide several ecological goods and services, of which only two are considered here: namely, sediment generation and sediment entrapment. Both are deemed essential to the functioning of the Sodwana Bay economy. The replacement-cost method was used to estimate the annual financial cost of sediment provided to the study area if it were replaced by dredging. Sediment generation by the coral reefs was valued at R2.6–R4.8 million, and sediment entrapment valued at R71.8–R84.6 million, totalling between R74.4 million and R89.4 million (≈$5.6–$6.7 million, at R13.38/US$1) per year.  相似文献   
66.
洞庭湖生态系统最终服务价值评估   总被引:1,自引:0,他引:1  
生态系统最终服务指生态系统直接提供给人类的,由人类直接享用、消费、使用的生态系统服务,目前生态系统服务评估多将最终服务与中间服务混淆,造成重复计算。以洞庭湖为例,建立洞庭湖生态系统最终产品与服务评估指标体系,并综合运用市场价值法、替代工程法和旅行费用法评估洞庭湖提供给人类的生态经济价值。结果表明:洞庭湖生态系统服务总价值为2 154.22×108元/a,其中洪水调蓄和气候调节占总价值的88.69%,是洞庭湖的主导生态系统服务。评价的10项生态系统最终服务按价值量排序,依次为调蓄洪水气候调节淡水产品水资源供给原材料生产释氧休闲旅游固碳水质净化内陆航运。评估结果比较全面地反映了洞庭湖对人类福祉的直接贡献,不仅能提高公众和管理部门对洞庭湖生态系统服务的认知,也为管理部门管理洞庭湖提供了重要方向。  相似文献   
67.
以率先试点耕地保护基金的四川省成都市和尚未实行耕地保护经济补偿制度的湖北省武汉市43个村庄430名受访农民为实证,建立微观经济模型分析基本农田用途管制对不同区域农民家庭农业收入及农业劳动力配置的影响,测算基本农田用途管制给农民家庭造成的福利损失、影响因素及区域差异。研究发现:1农民个体特征及其所在区域特征显著影响基本农田用途管制的实施成效;2基本农田用途管制明显提升受访农民的家庭农业收入及农业劳动力配置,但受粮食作物比较利益低下、农地经营规模等的影响,武汉农民农业收入的相对增加量要高于成都农民,同时作物种植结构等的差异使武汉农民的家庭农业劳动力配置低于成都农民;3经济补偿政策一定程度缓和了基本农田发展权受限给农民福利带来的影响。  相似文献   
68.
We examined the Hulun Lake protected area (HLPA) and tourist willingness to pay (WTP) for ecotourism resources using the contingent valuation method (CVM). Eight hundred questionnaires were distributed in the HLPA and 708 questionnaires were collected. To establish the relationship between variables and WTP, 11 variables were incorporated into the model. Social trust factors and awareness factor were for the first time applied to the models, and two bid equations were obtained by the first and second bid. We found that tourist WTP for ecotourism resources in the HLPA was CNY 14 710 389 in 2010, indicating that tourists have a large WTP for protected area ecotourism resources. Most tourists (79.9%) were willing to pay for ecotourism resources and 21.1% tourists were unwilling to pay. The most common explanation for unwillingness to pay was that it was the government’s responsibility, influenced by special social and economic characteristics in China and indicating that Chinese residents lack resource protection awareness and participation. Income and the awareness of being in a protected area most significantly affected WTP. Trusting protected area authorities significantly affected WTP. Tourists’ satisfaction affected WTP negatively in the first equation and WTP positively in the second equation. These results reveal that tourists had large WTP for ecotourism resources. To improve the WTP for ecotourism resources, the protected area management department could use third-party monitoring mechanisms and accounting systems to strengthen tourists’ trust, and increase ecological education and modify the “one site, several brands” management system.  相似文献   
69.
袁瑞娟  李凯琳 《地理科学》2018,38(7):1183-1188
以流经浙江北部的重要河流东苕溪流域为研究区域,从社会效益的视角,遵循意愿调查评估法的思想和技术,估算东苕溪流域居民对水质改善的支付意愿金额,分析影响支付意愿的主要因素。结果发现:357份有支付意愿,占问卷的65.9%,支付意愿范围为104.01~128.54元,中位数的支付意愿为115.63元/(a·户); 185份零支付愿意,占问卷的34.1%。其中影响流域居民支付意愿度的主要因素为:水质改善应为政府或企业的责任,流域居民不应是水质改善的承担者。同时,家庭人口数、文化程度、是否知道其饮用水源来自东苕溪与支付愿意度成正相关,对自家自来水状况的评价与支付意愿成负相关。基于此,研究提出适当增加水费用于水质改善;建立水环境信息制度,引导广大居民参与决策;严格执行环保标准,减少企业污染物排放等建议。  相似文献   
70.
Despite increasing attention paid to the value of marine resources, in particular marine protected areas (MPAs), their economic valuation focuses mainly on use values of ecosystem services such as fishery and tourism. Furthermore, most MPA related studies are carried out for coastal ecosystems, especially tropical coral reefs. The valuation of remote marine ecosystems is rare. The main objective of this paper is to estimate public willingness to pay (WTP) for alternative management regimes of a network of offshore MPAs in the North Sea under the Marine Strategy Framework Directive (MSFD). In a baseline valuation study carried out just before the adoption of the MSFD, beach visitors and a random sample of coastal and non-coastal residents were asked for their preferences for two alternative management options of three remote, ecologically sensitive areas with multiple use conflicts. Despite the lack of public awareness and familiarity with the offshore marine areas, a majority of 70% is willing to pay extra tax for their protection. Using a conservative value elicitation procedure, Dutch households are willing to pay on average maximum 0.25% of their annual disposable income to ban access and economic use. This serves as an indicator of what a network of remote MPAs in the MSFD is allowed to cost according to the Dutch tax payer.  相似文献   
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