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61.
Wetland ecosystems conservation is a critical environmental policy and practice challenge. Though policy protection mechanisms ostensibly establish a commitment to long-term protection, the level and types of wetland threats are growing. Management of sustainable wetland resources requires community commitments to protection amongst predominantly rural stakeholders that draw upon wetland ecosystem services for their livelihoods and is vital to forming a policy strategy. This empirical study uses contingent valuation methodology with rural residents around four key wetlands areas in the ecologically fragile Khuzestan province in Iran. We find that 65% of the residents are willing to pay an amount of personal income to protect wetland ecosystems. The estimated Logit model with 84% prediction accuracy showed the variables of education and job relationship with the wetland had a positive effect on the probability of price acceptance, and the variables of living costs and marital status had a negative effect on the probability of price acceptance. In total, the conservation value of wetlands is estimated at 103351.52 USD. Finally, we assess the policy-relevance of our findings towards community windfall payments, tax disbursements, community resource management schemes, public participation, and social outreach programs to improve social learning buy-in to long-term conservation practices.  相似文献   
62.
谢慧明  毛狄  沈满洪 《生态学报》2022,42(16):6633-6643
上游居民实践中甚少收到生态补偿资金,流域生态补偿的普惠性亟需提高。普惠的生态补偿不仅要增加上游居民的获得感,还要通过准确把握上游居民接受生态补偿意愿及其偏好让他们得以获得与生态增益行为贡献相匹配的补偿。以中国首个跨省流域生态补偿机制试点——新安江流域生态补偿为例,基于条件价值法研究了上游居民接受生态补偿的意愿及其影响因素。研究发现:(1)上游地区基于居民最小受偿意愿的合意生态补偿规模约为165.60亿元/a,其中浙江淳安县和安徽黄山市的合意受偿规模分别为44.32亿元/a和121.28亿元/a。(2)上游居民的受偿意愿随其年龄和家庭人口数的增加而提高,农村居民的补偿诉求比城镇居民更高,收入变化带来的受偿意愿边际变化约为0.04。(3)淳安县居民受到的环境规制强度偏高,他们的受偿意愿也更高;上游居民参加环保志愿活动的频率与他们的受偿意愿正相关。(4)上游居民感知的政府环保投入负担与实际负担不匹配,流域政府需增加有效生态公众宣传以实现政府环保投入和治理成效的价值。(5)异地移民就业安置政策在一定程度上可以缓解补偿资金缺口压力和地方有效就业压力。  相似文献   
63.
蔡志坚  杜丽永  蒋瞻 《生态学报》2011,31(10):2915-2923
CVM可靠性、有效性改善源于CVM范围效应、WTA与WTP之差、引导技术选择、假想偏差、信息效应、策略偏差和次序效应等7种偏差和误差的降低。以长江流域南京段生态系统恢复条件价值评估为例,对CVM有效性、可靠性改善的理论和方法进行了应用,具体包括:(1)选用WTP而非WTA的估值方式;(2)选用二分式选择法作为问卷的引导技术,并利用开放式和支付卡式问卷进行二次预调查以获得二分式选择问卷的核心估值;(3)以图文并茂的方式向受访者介绍调查背景,并用受访者更熟悉的"长江水质恢复到可游泳水平"替代所要评估的环境物品"长江流域生态系统恢复";(4)分析受访者意图以区分抗议性回答和真实零支付;(5)采用分层随机抽样的方式选取并发放大样本;(6)调查中采用面对面的方式并培训调查员;(7)选用切实可行但强制性高的支付工具;(8)利用中值法而非均值法估计WTP分布函数;(9)选择对数模型而非水平估算模型测算WTP值。综合利用上述方法所测得的南京市居民对长江流域生态系统恢复的支付意愿为270.7元/(户· a),此研究结果可为南京市制定"十二五"水价改革方案提供科学依据。  相似文献   
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65.
创新药研发对企业研发能力要求高,目前我国大部分药企仍然处于仿创阶段,但随着政策环境的改善,国家不断释放鼓励创新信号, 临前所未有的挑战,呼唤历史发展的转折点。 3.1 由仿到创的大型创新药企——1.0模式 2015 年临床数据自查、仿制药一致性评价、化学药 国内当下的政策环境和市场环境,使得我国创新 品注册分类改革工作方案、上市许可人制度试点、药监市 朱迅 创新型药企不断涌现,传统药企积极布局,创新药物迎来发展机遇。借鉴国外创新药研发经验,探讨我国创新药的 3 种研发模式及估值方法, 解析创新药研发的机遇与风险。  相似文献   
66.
我国重点保护动植物物种价值评估   总被引:1,自引:0,他引:1  
对野生动植物生态经济价值的认识是有效保护的基础,运用条件价值评估法对我国重点保护动植物物种的价值进行研究。通过网络问卷调查法共收集到5500份问卷,其中有效问卷4672份。通过对有效问卷分析得到总的平均支付意愿为209元人~(-1)a~(-1)。其中,动物和植物分别是111.37元人~(-1)a~(-1)和97.65元人~(-1)a~(-1),不同保护级别物种的支付意愿大小差别显著。基于2016年全国城镇就业人口数据求得我国重点保护动植物物种的保护效益为18.29万亿元/a,其中动物8.20万亿元/a,植物10.09万亿元/a。支付意愿影响因素分析表明,收入、学历、对重点保护物种的了解和感兴趣程度以及是否参加过重点保护物种保护活动对支付意愿大小有显著影响。  相似文献   
67.
王朋薇  钟林生 《生态学报》2018,38(15):5279-5286
生态系统服务价值评估是生态系统保护和管理的基础。以往研究采用多种方法对生态系统服务价值进行评估,但是至今还未形成得到一致认可的生态系统服务价值的评估方法。协商货币评估法(Deliberative Monetary Valuation,DMV)将协商方法和陈述偏好法相结合,成为一种正在探索使用的新的货币评估法。分析了DMV的研究背景,并从DMV的独特适用性、DMV在生态系统服务价值评估中的应用、DMV获得价值的性质3个方面总结了DMV的主要研究内容,在此基础上阐述了DMV面临的挑战,并提出了DMV在中国生态系统价值评估应用中的启示,以期能够为DMV在中国的应用及推广提供借鉴,为生态系统服务价值评估探索更有效的方法。  相似文献   
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69.
Background This article describes two projects conducted recently by Sound Resource Management (SRMG) – one for the San Luis Obispo County Integrated Waste Management Authority (SLO IWMA) and the other for the Washington State Department of Ecology (WA Ecology). For both projects we used life cycle assessment (LCA) techniques to evaluate the environmental burdens associated with collection and management of municipal solid waste. Both projects compared environmental burdens from curbside collection for recycling, processing, and market shipment of recyclable materials picked up from households and/or businesses against environmental burdens from curbside collection and disposal of mixed solid waste. Method logy. The SLO IWMA project compared curbside recycling for households and businesses against curbside collection of mixed refuse for deposition in a landfill where landfill gas is collected and used for energy generation. The WA Ecology project compared residential curbside recycling in three regions of Washington State against the collection and deposition of those same materials in landfills where landfill gas is collected and flared. In the fourth Washington region (the urban east encompassing Spokane) the WA Ecology project compared curbside recycling against collection and deposition in a wasteto- energy (WTE) combustion facility used to generate electricity for sale on the regional energy grid. During the time period covered by the SLO study, households and businesses used either one or two containers, depending on the collection company, to separate and set out materials for recycling in San Luis Obispo County. During the time of the WA study households used either two or three containers for the residential curbside recycling programs surveyed for that study. Typically participants in collection programs requiring separation of materials into more than one container used one of the containers to separate at least glass bottles and jars from other recyclable materials. For the WA Ecology project SRMG used life cycle inventory (LCI) techniques to estimate atmospheric emissions of ten pollutants, waterborne emissions of seventeen pollutants, and emissions of industrial solid waste, as well as total energy consumption, associated with curbside recycling and disposal methods for managing municipal solid waste. Emissions estimates came from the Decision Support Tool (DST) developed for assessing the cost and environmental burdens of integrated solid waste management strategies by North Carolina State University (NCSU) in conjunction with Research Triangle Institute (RTI) and the US Environmental Protection Agency (US EPA)1. RTI used the DST to estimate environmental emissions during the life cycle of products. RTI provided those estimates to SRMG for analysis in the WA Ecology project2. For the SLO IWMA project SRMG also used LCI techniques and data from the Municipal Solid Waste Life- Cycle Database (Database), prepared by RTI with the support of US EPA during DST model development, to estimate environmental emissions from solid waste management practices3. Once we developed the LCI data for each project, SRMG then prepared a life cycle environmental impacts assessment of the environmental burdens associated with these emissions using the Environmental Problems approach discussed in the methodology section of this article. Finally, for the WA study we also developed estimates of the economic costs of certain environmental impacts in order to assess whether recycling was cost effective from a societal point of view. Conclusions Recycling of newspaper, cardboard, mixed paper, glass bottles and jars, aluminum cans, tin-plated steel cans, plastic bottles, and other conventionally recoverable materials found in household and business municipal solid wastes consumes less energy and imposes lower environmental burdens than disposal of solid waste materials via landfilling or incineration, even after accounting for energy that may be recovered from waste materials at either type disposal facility. This result holds for a variety of environmental impacts, including global warming, acidification, eutrophication, disability adjusted life year (DALY) losses from emission of criteria air pollutants, human toxicity and ecological toxicity. The basic reason for this conclusion is that energy conservation and pollution prevention engendered by using recycled rather than virgin materials as feedstocks for manufacturing new products tends to be an order of magnitude greater than the additional energy and environmental burdens imposed by curbside collection trucks, recycled material processing facilities, and transportation of processed recyclables to end-use markets. Furthermore, the energy grid offsets and associated reductions in environmental burdens yielded by generation of energy from landfill gas or from waste combustion are substantially smaller then the upstream energy and pollution offsets attained by manufacturing products with processed recyclables, even after accounting for energy usage and pollutant emissions during collection, processing and transportation to end-use markets for recycled materials. The analysis that leads to this conclusion included a direct comparison of the collection for recycling versus collection for disposal of the same quantity and composition of materials handled through existing curbside recycling programs in Washington State. This comparison provides a better approximation to marginal energy usage and environmental burdens of recycling versus disposal for recyclable materials in solid waste than does a comparison of the energy and environmental impacts of recycling versus management methods for handling typical mixed refuse, where that refuse includes organics and non-recyclables in addition to whatever recyclable materials may remain in the garbage. Finally, the analysis also suggests that, under reasonable assumptions regarding the economic cost of impacts from pollutant emissions, the societal benefits of recycling outweigh its costs.  相似文献   
70.
Understanding the economic value of a wetland as well as how people perceive its role in providing goods and services can provide insight into the wetland's actual role and the kinds of policies needed to ensure sustainable use. On the island of Kosrae, Federated States of Micronesia, freshwater forested wetlands dominated by Terminalia carolinensis (hereafter called Terminalia) are often found just upslope from mangrove forests, which appear to be hydrologically connected to them. Many of these Terminalia forests have been converted into agroforests. A survey of 10% of the households on Kosrae showed that 89% owned some Terminalia land. Most grew taro, bananas, and sugar cane, either in or immediately adjacent to Terminalia forests. Most owned canoes constructed of Terminalia logs, and nearly half had harvested trees from these forests during the past year: 64% to clear land for agricultural purposes, 36% for building canoes, and 31% for other uses. Terminalia forests provided over $3.1 million worth of goods to Kosraeans, primarily from agricultural production. Approximately 2/3 of those surveyed understood that Terminalia grows best in a wetland setting. Most thought that Terminalia forests provide erosion protection and improve water quality. However, very few were cognizant of the ecological links between Terminalia and mangrove forests. Kosraeans attached little importance to the fact that Terminalia is endemic to the eastern Caroline Islands. If human dependence on these wetlands increases, the integrity of Terminalia forests, as well as adjacent mangrove forests, could be at risk.  相似文献   
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