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191.
Understanding the effects of different social data on selecting priority conservation areas
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Conservation success is contingent on assessing social and environmental factors so that cost‐effective implementation of strategies and actions can be placed in a broad social–ecological context. Until now, the focus has been on how to include spatially explicit social data in conservation planning, whereas the value of different kinds of social data has received limited attention. In a regional systematic conservation planning case study in Australia, we examined the spatial concurrence of a range of spatially explicit social values and land‐use preferences collected using a public participation geographic information system and biological data. We used Zonation to integrate the social data with the biological data in a series of spatial‐prioritization scenarios to determine the effect of the different types of social data on spatial prioritization compared with biological data alone. The type of social data (i.e., conservation opportunities or constraints) significantly affected spatial prioritization outcomes. The integration of social values and land‐use preferences under different scenarios was highly variable and generated spatial prioritizations 1.2–51% different from those based on biological data alone. The inclusion of conservation‐compatible values and preferences added relatively few new areas to conservation priorities, whereas including noncompatible economic values and development preferences as costs significantly changed conservation priority areas (48.2% and 47.4%, respectively). Based on our results, a multifaceted conservation prioritization approach that combines spatially explicit social data with biological data can help conservation planners identify the type of social data to collect for more effective and feasible conservation actions. 相似文献
192.
Around the world it has proven very difficult to develop policies and interventions that ensure socio-environmentally sustainable groundwater use and exploitation. In the state of Guanajuato, Central Mexico, both the national government and the decentralized state government have pursued to regulate groundwater use through direct state control, groundwater markets, energy pricing, and user self-regulation. We present and analyze these regulatory mechanisms and their outcomes in the field. We argue that the close interdependencies of these regulatory mechanisms have pre-empted the effectiveness of these policy instruments as well as that of other measures aimed at reducing groundwater use in order to advance towards sustainable exploitation levels. 相似文献
193.
Hydrofluorocarbons (HFCs) are synthetically produced compounds primarily used for cooling purposes and with strong global warming properties. In this paper, we analyze the global abatement costs for achieving the substantial reductions in HFC consumption agreed in the Kigali Amendment (KA) of the Montreal Protocol from October 2016. We estimate that compliance with the KA is expected to remove 39 Pg CO2eq or 61% of global baseline HFC emissions over the entire period 2018–2050. The marginal cost of meeting the KA targets is expected to remain below 60 €/t CO2eq throughout the period in all world regions except for developed regions where legislation to control HFC emissions has already been in place since a few years. For the latter regions, the required HFC consumption reduction is expected to come at a marginal cost increasing steadily to between 90 and 118 €/t CO2eq in 2050. Depending on the expected rate of technological development and the extent to which envisaged electricity savings can be realized, compliance with KA is estimated attainable at a global cost ranging from a net cost-saving of 240 billion € to a net cost of 350 billion € over the entire period 2018 to 2050 and with future global electricity-savings estimated at between 0.2% and 0.7% of expected future electricity consumption. 相似文献
194.
ANNI ARPONEN MAR CABEZA JOHANNA EKLUND HEINI KUJALA JOONA LEHTOMÄKI 《Conservation biology》2010,24(5):1198-1204
Abstract: Recent literature on systematic conservation planning has focused strongly on economics. It is a necessary component of efficient conservation planning because the question is about effective resource allocation. Nevertheless, there is an increasing tendency toward economic factors overriding biological considerations. Focusing too narrowly on economic cost may lead us back toward solutions resembling those obtained by opportunistic choice of areas, the avoidance of which was the motivation for development of systematic approaches. Moreover, there are many overlooked difficulties in incorporating economic considerations reliably into conservation planning because available economic data and the free market are complex. For instance, economies based on free markets tend to be shortsighted, whereas biodiversity conservation aims far into the future. Although economic data are necessary, they should not be relied on too heavily or considered separately from other sociopolitical factors. We suggest focusing on development of more‐comprehensive ecological‐economic modeling, while not forgetting the importance of purely biological analyses that are needed as a point of reference for evaluating conservation outcomes. 相似文献
195.
排污权交易定价下的COD和氨氮削减成本分析研究 总被引:1,自引:0,他引:1
调查测算了工业废水COD和氨氮削减成本并进行了分析。总成本中折旧费和日常运行费各占35%和65%;COD和氨氮削减成本为1 287元/t~29 035元/t和2 433元/t~46 560元/t,加权均值为4 936元/t和17 755元/t,二者之比为3.60∶1,90%置信区间为(4 647,8 514)和(13 989,24 617);70%和63.2%的企业以6 837元/t和20 083元/t以内的成本削减了73.7%的COD和42.1%的氨氮。不同企业和行业COD和氨氮削减成本差异明显,以概率分布确定综合成本用于排污权交易定价可能更合理。 相似文献
196.
Janthawan Wantanaphong Sacha Jon Mooney Elizabeth Helen Bailey 《Environmental Chemistry Letters》2005,3(1):19-23
A range of waste products and natural materials including chitin, fly ash, clay soil, cocoa shell, calcified seaweed and the natural zeolite clinoptilolite were tested in batch experiments to assess their ability to remove metals from a synthetic groundwater containing 10 mg l–1 Cu, Pb and Zn and 1 mg l–1 Cd. All had the ability to remove more than 70% of the metals from solution with fly ash being the most efficient, then chitin, clinoptilolite, calcified seaweed, clay soil and cocoa shell. After consideration of geochemical and morphological properties, calcified seaweed and clinoptilolite were shown to have potential as barrier materials. Given current issues with regard to the longevity of zero-valent iron barriers alternative materials could be the key to the future adoption of this remediation technology. 相似文献
197.
全世文 《中国人口.资源与环境》2017,(9):46-55
科学地评估空气质量的经济价值是政府制定空气污染治理政策的必要前提。近年来选择实验方法逐渐兴起,并被研究者广泛应用于环境价值评估。与其他陈述偏好方法相比,选择实验的一个优势是其具有更高的外部效度。选择实验方法在国内的应用研究尚处在起步阶段。本研究分别在2015年和2016年对北京市居民开展了两次基于选择实验方法的网络调查,在调查数据的基础上采用随机参数Logit和广义多元Logit模型分析了北京市居民对空气质量的偏好,并据此估算了空气质量价值。根据2015年样本的估算结果,雾霾天气(PM_(2.5)超标)和沙尘天气(PM_(10)超标)对北京市居民的平均边际价值分别为6.32元/d和2.69元/d;根据2016年样本的估算结果,两个价值分别为7.72元/d和2.81元/d。上述估算结果在两次调查样本中基本稳定,而且,在多种模型设定下都具有较强的稳健性,与近年来的同类研究结果基本一致。以2016年样本的估算结果为基础,2015年北京市雾霾天气和沙尘天气引起的价值损失分别为239.61亿元和45.13亿元,占北京市当年GDP总量的1.04%和0.20%。进一步研究发现,北京市2015年和2016年空气质量改善的价值均低于北京市政府同年用于治理空气污染投入的财政资金总量,说明资金使用效率有待进一步提高;此外,虽然空气质量对高收入居民具有更高的价值,但是,以收入水平为指标设计的累进税率并不比固定税率更优。 相似文献
198.
Abstract: The unit of trade in ecosystem services is usually the use of a proportion of the parcels of land associated with a given service. Valuing small changes in the provision of an ecosystem service presents obstacles, particularly when the service provides non‐use benefits, as is the case with conservation of most plants and animals. Quantifying non‐use values requires stated‐preference valuations. Stated‐preference valuations can provide estimates of the public's willingness to pay for a broad conservation goal. Nevertheless, stated‐preference valuations can be expensive and do not produce consistent measures for varying levels of provision of a service. Additionally, the unit of trade, land use, is not always linearly related to the level of ecosystem services the land might provide. To overcome these obstacles, we developed a method to estimate the value of a marginal change in the provision of a non‐use ecosystem service—in this case conservation of plants or animals associated with a given land‐cover type. Our method serves as a tool for calculating transferable valuations of small changes in the provision of ecosystem services relative to the existing provision. Valuation is achieved through stated‐preference investigations, calculation of a unit value for a parcel of land, and the weighting of this parcel by its ability to provide the desired ecosystem service and its effect on the ability of the surrounding land parcels to provide the desired service. We used the water vole (Arvicola terrestris) as a case study to illustrate the method. The average present value of a meter of water vole habitat was estimated at UK£12, but the marginal value of a meter (based on our methods) could range between £0 and £40 or more. 相似文献
199.
Abstract: Populations at the periphery of a species' range are of interest to conservation biologists because they can show marked genetic differentiation from populations at the center of a range and because of potential hybridization among rare and common species. We examined two closely related Cyclamen species. One is a narrow endemic, and the other is more geographically widespread (both protected by law in continental southern France). We used floral traits and genetic variability to test for hybridization among the species in peripheral populations of the rare species. The species co-occurred on Corsica in a disjunct, peripheral part of the distribution of the endemic species and in an ecologically marginal area for the widespread species. The two species have hybridized and the endemic species showed high levels of introgression with its widespread congener. Genetic and floral variability in sites with both species was markedly higher than in sites with a single species. Our results highlight the need for a conservation strategy that integrates hybrid populations because they represent a source of novel diversity that may have adaptive potential. 相似文献
200.
Seema Bathla 《Environment, Development and Sustainability》1999,1(2):105-121
The paper examines the linkages between water depletion, continuous population growth and economic development viewed primarily as agricultural development. This is done within a framework of a dynamic simulation model of ecological-economic type over extended periods of time. It is found that intensive agriculture, driven by an increase in the cropping intensity as a result of increase in area under paddy crop, has led to an increased gap between the demand for and supply of water resources, in particular subsurface resources. The consequent fall in water table may lead to constraints in the use of water. This has strong inequity implications in the resource use as well as threats to future of agricultural development in the region. It is revealed that a mix of interventions based on price solutions, non-price solutions and institutional set up are decisive in bringing a sustainable development and use of resource. The paper concludes with emphasising the role of state/government in achieving the desired goal. 相似文献