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1.
This paper explores the economics and politics of the siting of noxious facilities. In the base case, facilities are sited by markets, subject to majority agreement in the host jurisdiction. By contrast with the existing market siting literature-which assumes that all the disamenities of a facility will be contained in the host jurisdiction and fully reflected in the jurisdiction′s willingness to accept-here facilities impose disamenities on individuals as a function of distance, and the process of majority agreement is explicitly modeled. The principal finding is that when voters are uniformly distributed within a jurisdiction, an individual who is median distance from a facility suffers less than average (mean) disamenity. Therefore a majority would be willing to serve as facility host for a price (host fee) that is strictly less than the aggregate disamenity that the facility imposes on the jurisdiction. Further, by threatening the equilibrium host with a site just across its border, a firm can induce majority acceptance of a nontrivial facility at zero host fee. Even when this threat site strategy is infeasible, though, market-determined host fees will not signal efficient sites. Thus, markets will produce an excessive number of noxious facilities and place them in the wrong sites. These results are robust to alternative specifications of bargaining power and market structure. If, however, host majority agreement is subject to the veto of a higher jurisdiction-e.g., in response to cries of "NIMBY"-then efficiency may be either improved or reduced.  相似文献   

2.
Abstract:  To supply ecosystem services, private landholders incur costs. Knowledge of these costs is critical for the design of conservation-payment programs. Estimating these costs accurately is difficult because the minimum acceptable payment to a potential supplier is private information. We describe how an auction of payment contracts can be designed to elicit this information during the design phase of a conservation-payment program. With an estimate of the ecosystem-service supply curve from a pilot auction, conservation planners can explore the financial, ecological, and socioeconomic consequences of alternative scaled-up programs. We demonstrate the potential of our approach in Indonesia, where soil erosion on coffee farms generates downstream ecological and economic costs. Bid data from a small-scale, uniform-price auction for soil-conservation contracts allowed estimates of the costs of a scaled-up program, the gain from integrating biophysical and economic data to target contracts, and the trade-offs between poverty alleviation and supply of ecosystem services. Our study illustrates an auction-based approach to revealing private information about the costs of supplying ecosystem services. Such information can improve the design of programs devised to protect and enhance ecosystem services.  相似文献   

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Abstract:  We studied three new incentive-based programs for restoring endangered species on private lands in the United States: safe harbor, Environmental Defense's Landowner Conservation Assistance Program, and conservation banking. For each program, we gathered data on the number of participating landowners, the number of species targeted for assistance, and the cumulative acreage of enrolled land. Measured in this way, both safe harbor and the Landowner Conservation Assistance Program have been remarkably successful. Landowners are drawn to three aspects of these programs: (1) the removal of regulatory burdens associated with attracting endangered species to their property; (2) technical guidance on how to restore habitats for endangered species; and (3) cost-share assistance for habitat restoration. Technical guidance appears to be more important than either regulatory relief or financial assistance in securing the cooperation of some landowners. Assessing the success or failure of conservation banking proved more difficult, given the relatively small number of banks created to date and the lack of any centralized database on them. However, nearly half of the 47 endangered-species conservation banks we surveyed have sold credits, indicating some success in either acquiring or restoring essential habitats.  相似文献   

5.
盆栽试验表明,一次性水稻专用涂层复混肥一次性施用能满足水稻各生育期的需要,并能促进养分由稻秆向谷粒的转移,提高成穗率和产量,使用方便,节省劳力,有较好的推广应用前景。  相似文献   

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Although the word commitment is prevalent in conservation biology literature and despite the importance of people's commitment to the success of conservation initiatives, commitment as a psychological phenomenon and its operation in specific conservation behaviors remains unexplored. Despite increasing calls for conservation psychology to play a greater role in meeting conservation goals, applications of the psychological sciences to specific conservation behaviors, illustrating their utility to conservation practice, are rare. We examined conservation volunteers’ motivations and commitment to urban conservation volunteering. We interviewed key informant volunteers and used interview findings to develop psychometric scales that we used to assess motivations and commitment to volunteer. We surveyed 322 urban conservation volunteers and used factor analysis to reveal how volunteers structure their motivations and commitment to volunteer for urban conservation activities. Six categories of motivations and 2 categories of commitment emerged from factor analysis. Volunteers were motivated by desires to help the environment, defend and enhance the ego, career and learning opportunities, escape and exercise, social interactions, and community building. Two forms of commitment, affective and normative commitment, psychologically bind people to urban conservation volunteerism. We used linear‐regression models to examine how these categories of motivations influence volunteers’ commitment to conservation volunteerism. Volunteers’ tendency to continue to volunteer for urban conservation, even in the face of fluctuating counter urges, was motivated by personal, social, and community functions more than environmental motivations. The environment, otherwise marginally important, was a significant motivator of volunteers’ commitment only when volunteering met volunteers’ personal, social, and community‐building goals. Attention to these personal, social, and community‐building motivations may help enhance volunteers’ commitment to conservation stewardship and address the pressing challenge of retaining urban conservation volunteers. Implicaciones Prácticas del Entendimiento de la Influencia de Motivaciones sobre el Compromiso de Voluntarios de Conservación Urbana Asah & Blahna  相似文献   

8.
Abstract: The use of voluntary approaches to achieve conservation goals is becoming increasingly popular. Nevertheless, few researchers have quantitatively evaluated their efficacy. In 1998 industry, government agencies, and nongovernmental organizations established a voluntary conservation program for whale watching in the northeast region of the United States, with the intent to avoid collisions with and harassment of endangered whales by commercial and recreational whale‐watching vessels. One important aspect of the program was the establishment of 3 speed zones within specific distances of whales. We wanted to determine the level of compliance with this aspect of the program to gauge its efficacy and gain insights into the effectiveness of voluntary measures as a conservation tool. Inconspicuous observers accompanied 46 commercial whale‐watching trips from 12 companies in 2003 (n= 35) and 2004 (n= 11). During each trip, vessel position and speed were collected at 5‐second intervals with a GPS receiver. Binoculars with internal laser rangefinders and digital compasses were used to record range and bearing to sighted whales. We mapped whale locations with ArcGIS. We created speed‐zone buffers around sighted whales and overlaid them with vessel‐track and speed data to evaluate compliance. Speeds in excess of those recommended by the program were considered noncompliant. We judged the magnitude of noncompliance by comparing a vessel's maximum speed within a zone to its maximum recorded trip speed. The level of noncompliance was high (mean 0.78; company range 0.74–0.88), some companies were more compliant than others (p= 0.02), noncompliance was significantly higher in zones farther from whales (p < 0.001), and operators approached the maximum speed capabilities of their vessel in all zones. The voluntary conservation program did not achieve the goal of substantially limiting vessel speed near whales. Our results support the need for conservation programs to have quantifiable metrics and frequent evaluation to ensure efficacy.  相似文献   

9.
This paper assesses whether individuals change their transportation choices in response to ‘Spare the Air’ (STA) advisories, a public voluntary information program in the San Francisco Bay Area that elicits reductions in ozone-producing activities. Since STAs are issued when ozone levels are predicted to exceed a particular threshold, we use a regression discontinuity design to identify the effect of STAs. We also use traffic conditions in Southern California, an area without STAs, to estimate difference-in-differences models. The results suggest that STAs reduce traffic volume and slightly increase the use of public transit, supporting a potential role for voluntary information programs that directly target individuals as a means for improving local air quality.  相似文献   

10.
Abstract:  The identification of conservation areas based on systematic reserve-selection algorithms requires decisions related to both spatial and ecological scale. These decisions may affect the distribution and number of sites considered priorities for conservation within a region. We explored the sensitivity of systematic reserve selection by altering values of three essential variables. We used a 1:20,000–scale terrestrial ecosystem map and habitat suitability data for 29 threatened vertebrate species in the Okanagan region of British Columbia, Canada. To these data we applied a reserve-selection algorithm to select conservation sites while altering selection unit size and shape, features of biodiversity (i.e., vertebrate species), and area conservation targets for each biodiversity feature. The spatial similarity, or percentage overlap, of selected sets of conservation sites identified (1) with different selection units was ≤40%, (2) with different biodiversity features was 59%, and (3) with different conservation targets was ≥94%. Because any selected set of sites is only one of many possible sets, we also compared the conservation value (irreplaceability) of all sites in the region for each variation of the data. The correlations of irreplaceability were weak for different selection units (0.23 ≤ r ≤ 0.67), strong for different biodiversity features ( r = 0.84), and mixed for different conservation targets ( r = 0.16; 0.16; 1.00). Because of the low congruence of selected sites and weak correlations of irreplaceability for different selection units, recommendations from studies that have been applied at only one spatial scale must be considered cautiously.  相似文献   

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Abstract: Ecosystem services are being protected and restored worldwide through payments for ecosystem services in which participants are paid to alter their land‐management approaches to benefit the environment. The efficiency of such investments depends on the design of the payment scheme. Land features have been used to measure the environmental benefits of and amount of payment for land enrollment in payment for ecosystem services schemes. Household characteristics of program participants, however, may also be important in the targeting of land for enrollment. We used the characteristics of households participating in China's Grain‐to‐Green program, and features of enrolled land to examine the targeting of land enrollment in that program in Wolong Nature Reserve. We compared levels of environmental benefits that can be obtained through cost‐effective targeting of land enrollment for different types of benefits under different payment schemes. The efficiency of investments in a discriminative payment scheme (payments differ according to opportunity costs, i.e., landholders’ costs of forgoing alternative uses of land) was substantially higher than in a flat payment scheme (same price paid to all participants). Both optimal targeting and suboptimal targeting of land enrollment for environmental benefits achieved substantially more environmental benefits than random selection of land for enrollment. Our results suggest that cost‐effective targeting of land through the use of discriminative conservation payments can substantially improve the efficiency of investments in the Grain‐to‐Green program and other payment for ecosystem services programs.  相似文献   

13.
Abstract:  Scarce resources and competing land-use goals necessitate efficient biodiversity conservation. Combining multicriteria analysis with conservation decision-support tools improves efficiency of conservation planning by maximizing outcomes for biodiversity while minimizing opportunity costs to society. An opportunity cost is the benefit that could have been received by taking an alternative course of action (i.e., costs to society of protecting an area for biodiversity rather than developing it for some other use). Although different ways of integrating multiple opportunity costs into conservation planning have been suggested, there have been no tests as to which method is most efficient. We compared the relative efficiency of 3 such procedures ( Faith & Walker [1996] , Sarkar et al. [2004] , and a procedure of our own design) in a systematic conservation-planning framework for the Milne Bay Province of Papua New Guinea. We devised 14 opportunity costs and assigned these to 3 scenarios representing different conservation planning concerns: food security, macro-economic development, and biodiversity persistence. For each scenario, we compared the efficiency of the 3 methods in terms of amount of biodiversity protected relative to total expenditure for each opportunity cost. All 3 methods captured similar amounts of biodiversity, but differed in total cost. Our method had the least overall cost and was therefore most efficient. Nevertheless, there was a high correlation and geographical concordance among all 3 methods, indicating a high degree of spatial overlap. This suggests that choosing an appropriate approach may often depend on contextual factors related to the design of the planning question, rather than efficiency alone.  相似文献   

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比较老年患者下肢手术罗哌卡因与布比卡因蛛网膜下腔阻滞效果.方法:择期骨科下肢手术的高龄病人80例,随机分为两组,R组(n=40)蛛网膜下腔注入5mg/ml罗哌卡因3ml,B组(n=40)蛛网膜下腔注入5mg/ml布比卡因3m1.采用针刺法评估感觉阻滞效果,记录感觉阻滞起效时间、运动阻滞起效时间、最高感觉阻滞平面、麻醉维持时间、术中麻醉质量与肌松效果及用药后的不良反应.结果:与B组比较,R组运动阻滞起效时间较长,运动阻滞和感觉阻滞维持时间较短(P〈0.05);感觉阻滞起效时间差异无统计学意义(P〉O.05);两组麻醉质量和肌松效果均较好,麻醉质量及肌松效果无统计学差异(P〉0.05);两组不良反应发生率均较低,且差异无统计学意义(P〉0.05).结论:老年病人下肢手术患者采用罗哌卡因蛛网膜下腔阻滞术中麻醉质量及肌松效果良好,且其运动阻滞维持时间较布比卡因短,有利于术后的恢复和功能锻炼.表4,参7.  相似文献   

16.
本文详细分析了康集生态农场建设初期的能流结构及生态效率。结果表明,经过5年的开发,康集生态农场已初步建成具有较复杂的网络式能流系统。系统的能量利用与转化效率逐年提高,其中种植业和家畜家禽饲养业的能量利用率较高,而养鱼业的能量转化率低,在能量利用上潜力极大。第二性生产的绝大部分人工辅助能依靠系统外输入。据此提出了提高康集生态农场能量利用效率的调控措施。  相似文献   

17.
Oxidants were proposed to rapidly control black and odorous substances in sediments. NaClO and KMnO4 had excellent efficiency to remove black and odorous substances. NaClO dramatically accelerated the release of organics, NH4+-N, P, and heavy-metals. Moderate oxidation had a limited effect on microbial communities. NaClO of 0.2 mmol/g was viewed to be the optimum option. The control of black and odorous substances in sediments is of crucial importance to improve the urban ecological landscape and to restore water environments accordingly. In this study, chemical oxidation by the oxidants NaClO, H2O2, and KMnO4 was proposed to achieve rapid control of black and odorous substances in heavily-polluted sediments. Results indicate that NaClO and KMnO4 are effective at removing Fe(II) and acid volatile sulfides. The removal efficiencies of Fe(II) and AVS were determined to be 45.2%, 94.1%, and 93.7%, 89.5% after 24-h exposure to NaClO and KMnO4 at 0.2 mmol/g, respectively. Additionally, rapid oxidation might accelerate the release of pollutants from sediment. The release of organic matters and phosphorus with the maximum ratios of 22.1% and 51.2% was observed upon NaClO oxidation at 0.4 mmol/g. Moreover, the introduction of oxidants contributed to changes in the microbial community composition in sediment. After oxidation by NaClO and KMnO4 at 0.4 mmol/g, the Shannon index decreased from 6.72 to 5.19 and 4.95, whereas the OTU numbers decreased from 2904 to 1677 and 1553, respectively. Comparatively, H2O2 showed a lower effect on the removal of black and odorous substances, pollutant release, and changes in sediment microorganisms. This study illustrates the effects of oxidant addition on the characteristics of heavily polluted sediments and shows that chemical oxidants may be an option to achieve rapid control of black and odorous substances prior to remediation of water environments.  相似文献   

18.
SOS/umu测试法被广泛应用于化合物和复杂混合物遗传毒性的评价,由于该技术所用菌种为致病菌且操作步骤繁琐等原因,制约了技术的推广应用。研究建立了基于重组大肠杆菌SOS效应的水质遗传毒性检测方法(专利号:ZL201110022476.1),应用该方法评价了某市4座污水厂出水的直接遗传毒性效应,同时以污水处理一厂为例考察了直接遗传毒性效应的季节变化规律以及不同的工艺对水中直接遗传毒性物质的去除情况。结果显示:各污水厂出水均表现出一定的直接遗传毒性,对应的4-NQO毒性当量浓度范围为0.018~0.514 mg·L-1;一年四季中夏季进出水直接遗传毒性效应最高,现有工艺中生化处理工艺段对直接遗传毒性去除效果最佳,去除率为33.33%。该方法操作便利、检测敏感性较高、操作危险性较低,可用于水中直接遗传毒性效应的测试。  相似文献   

19.
Recruitment helps insect societies by bringing individuals to places where work needs to be done, but it also imposes energetic and opportunity costs. The net effect depends both on recruitment efficiency and on the ease with which insects can find work sites on their own. This study examined both of these factors for colony emigration by the ant Temnothorax curvispinosus. Emigrations were organized by a corps of active ants who transported the rest of the colony. These active ants either found new sites independently or followed tandem runs led by successful scouts. Although most tandem runs broke apart before reaching their target, even lost followers found the new site faster than did unguided searchers. When the new site was near the old nest, tandem runs were rare and summoned only a small proportion of the transporter corps. When the new site was instead distant and inconspicuous, tandem runs were common and brought roughly one third of the transporters. This pattern likely results from the quorum rule used by individual scouts to decide when to switch from tandem runs to transports. By monitoring how many nestmates have already found the nest, the ants ensure that the costs of recruitment are born only when necessary.  相似文献   

20.
在普遍尿素的生产工艺中分别加入一定比例的无机矿物改性剂,研制出3种改性尿素。盆栽结果显示,在等质量及等N施肥条件下,3种改性尿素均有较大幅度的增产。淋溶实验表明,改性尿素与德国缓释尿素的淋溶曲线相似。  相似文献   

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