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41.
Payment for ecosystem services schemes (PES) are lauded as a market-based solution to curtail deforestation and restore degraded ecosystems. However, PES programs often fail to conserve sites under strong long-term deforestation pressures. Underperformance, in part, is likely due to adverse selection. Spatial adverse selection occurs when landowners are more likely to enroll parcels with low deforestation pressure than parcels with high deforestation pressure. Temporal adverse selection arises when parcels are enrolled for short time periods. In both cases, financial resources are allocated without having a sizeable impact on long-term land use change. Improving program performance to overcome these shortcomings requires understanding attributes of landowners and their parcels across large scales to identify spatial and temporal enrollment patterns that drive adverse selection. In this paper, we examine these patterns in Argentina’s PES program in Chaco forest, a global deforestation hotspot. Our study area covers 252,319 km2. Results from multinomial logistic regression models showed that large parcels of enrolled land and parcels owned by absentee landowners exhibit greater evidence of spatiotemporal adverse selection than smaller parcels or parcels owned by local landowners. Furthermore, parcels managed under land use plans for conservation and restoration are more likely to be associated with adverse selection than parcels managed for financial returns such as harvest of non-timber forest products, silviculture, and silvopasture. However, prior to recommending that PES programs focus on land uses with higher potential earnings, a greater understanding is needed of the degree to which these land uses meet ecological and biodiversity goals of PES programs. We suggest that increased spatial targeting of enrollment, along with enrollment of local landowners and further incentives for land uses that support conservation and restoration, could promote long-term conservation of forest lands.  相似文献   
42.
Recent advances in science mapping allowed to analyze the entire intellectual structure of blockchain and cryptocurrencies in business-related disciplines to identify 174 academic articles as well as 1482 practitioner-oriented articles published since the inception of cryptocurrencies in 2008 to highlight key trends of the published outputs. The results demonstrate academic research done by 389 authors in 296 organizations based in 50 countries that only just initiated the conversation on four major streams of the literature—Bitcoin and cryptocurrencies; blockchain adoption; cryptocurrency and blockchain environment; and business model innovations. When comparing academic scholarship to practitioner-oriented literature, the results demonstrate that practitioners discussed investor-related themes, cryptocurrency intrinsic value, political-economic sphere, and the impact of cryptocurrency and blockchain technologies on the wider society in greater detail. As a result, a number of themes are identified and discussed that could align academic and practitioner interests and provide guidance for further research in this important field.  相似文献   
43.
There seems to be widespread consensus in the ecosystem services literature that benefits from ecosystems are not produced by ecosystems independently of humans, but arise because of people’s interactions with an ecosystem. Yet, these interactions are hardly ever explicitly investigated in a way that directly contributes to the ecosystem services debate. Here, we empirically examine the role of humans in the generation of ecosystem services, and the factors that might help us to understand diversity in these processes.We analyzed 47 qualitative interviews with people using a mixed woodland–farmland–upland ecosystem in Fife, Scotland, for a variety of activities. Interviewees mentioned a wide range of ecosystem services, especially provisioning and cultural services, which were closely connected to human activities in the place. We term the interactions between people and place that lead to ecosystem services here ‘co-production’, and distinguish between: (a) the co-production of ecosystem structures; (b) the co-production of the services proper and (c) the attribution, i.e., construction, of meaning to these structures and services. All three processes could be carried out by individuals or jointly, by groups of people, and the social nature of the interaction often added meaning and value to the co-production process. Two sets of factors, clustered under the headings of ‘identities’ and ‘capabilities’, shaped these interactions, and helped us to understand variation in people’s engagement with the ecosystem as well as their views on ecosystem disservices.While further research is needed to explore the usefulness of our analytical framework in other contexts, our findings suggest that identities and capabilities of people have to be considered much more strongly than is currently the case in standard ecosystem services assessments, as these influence which ecosystem structures are eventually turned into benefits, and give important insights into the environmental justice related to the distribution of ecosystem benefits.  相似文献   
44.
Tourism, as all human activities, is dependent on the natural environment and its respective ecosystem services (ES). Different user groups manage and consume these touristic ES differently, resulting in discrepancies and potential conflicts. Despite the urgency to find inclusive local approaches for sustainable development, tourism studies still analyze socio-economic and ecological impacts separately and lack integrated social–ecological approaches to improve foresight in tourism planning. Based on a growing concern regarding the future of Costalegre on the Jalisco coast of Western Mexico, we analyze through interviews, surveys, and participant observation the dependence of tourism on specific ecosystem services and conduct a scenario analysis which shows present and future implications for the social–ecological system. Furthermore, this analysis shows in detail how different scenarios change ES provision and people's livelihoods. Key findings include identifying freshwater provision and cultural ES as the most important touristic ES. At a regional scale, peasants in ejidos are the main ES stewards, whereas high-class tourism facilities constitute important local stewards. Benefits, mainly access to freshwater and the beach, are unequally distributed, provoking conflicts among different ES user groups that may escalate in the near future. Improved communication between all user groups and strengthening of key political actors seem to be the most immediate recommendations to ensure the long term sustainability of this particular region. This work may contribute to improved planning and decision-making as our ES based scenarios are a first step to integrate social–ecological knowledge into improved decision-making. At a local scale, the study reveals the most likely future development options and their social and ecological consequences. It could also serve as a baseline for informed policy making.  相似文献   
45.
在当今社会,竞争涉及社会的各个领域,尤其是经济领域。而在经济领域,最重要,最突出的竞争就是品牌竞争。所谓企业品牌生态位就是企业在其品牌生态系统中所确定的"生态位",依据企业品牌生态位的形成探讨奥运赞助企业品牌的优势生态位,以此制定出奥运赞助企业品牌国际化的"生态"策略。  相似文献   
46.
中国快速城市化地区面临严重洪涝风险和洪涝调节 服务供需空间的分离。为识别在满足洪涝调节服务需求方面重 要性高的生态空间以纳入保护的优先级,提出了一种在生态空 间中绘制洪涝调节服务需求的新技术:基于生态系统服务空间 流,利用流量、流边界、流方向、分配原则及其修正因子4个 多维指标,表征将服务需求从建设空间向生态空间分配与投射 过程的关键环节。结果显示:面积大、人口密度高的建设空间 存在高需求流量;借助水文空间流,服务需求由建设空间被分 配至同一集水区内具有洪涝调节能力的生态空间中;被投射为 高服务需求的生态空间大多规模较大或紧邻高需求的建成空 间。通过控制流量、扩展流区域、增加流方向和提升生态空间 服务供应能力,能有效调控投射于生态空间内的洪涝调节服务 高需求。  相似文献   
47.
在分析城市生态系统健康评估研究进展的基础上,采用层次分析法建立城市生态系统健康评价指标体系,然后利用模糊数学模型,以天津市滨海新区为案例,进行城市生态系统健康评估。结果表明,近年来天津滨海新区城市生态系统处于亚健康状态,总体状况并没有明显改善。主要原因是在经济快速增长的同时,第二产业比重过高,能源消耗大量增加,环境质量较差,虽然投资力度加大,但仍有恶化趋势,未来改善压力大。如果不从整体上加大产业结构改善,加大环境保护和生态建设,将大大影响滨海新区的可持续发展。  相似文献   
48.
近十五年来,在品牌关系理论研究的热潮下,Munizεt&O’Guinn提出的全新概念"品牌社群"(brand community)受到广大实践工作者和学者们关注,成为西方品牌理论研究的新前沿。本文在对为数不多的品牌社群理论进行综述分析的基础上,提出了从生态学生态位角度研究品牌社群的全新视角。通过对品牌社群生态位内涵进行界定,以及对前人有关品牌生态系统层级构建进行完善的基础上,从生态位宽度和生态位重叠度层面构建品牌社群生态位测量模型,即运用一维生态因子轴来分析品牌社群对资源变量的占用幅度以及共享状态,表征该类社群处于生态系统环境中的相对地位,目的在于对生态位重叠态势下的竞争格局预先作出有效判断,从而在提升品牌社群决策科学性的同时,提升企业顾客资产以及品牌资产的价值。  相似文献   
49.
对循环经济理念的水资源管理及文献进行了综述,阐述了循环经济的基本概念、理论及相关的实践.最后,对于循环经济在水资源管理方面的运用进行了相关研究.  相似文献   
50.
Understanding spatial patterns of visitation and benefits accrued to different types of natural and cultural heritage tourists may have important implications for the sustainable management of their destinations. We investigate cultural services accrued to local, domestic and international visitors to the Usumacinta floodplain, a coastal region with one of the highest biological and cultural diversities in Mexico. We combine analysis of social media photographs and high-resolution land cover mapping to identify different cultural services and their association with specific ecosystem and land cover types. Hotspots for international tourists are spatially restricted to well-known and accessible sites. Locals are 2.2–2.5 times more likely than international visitors to be associated with aesthetic appreciation and birdwatching. Locals upload more photographs of coastal lagoons, mangroves, beach and sea. Results are analyzed in light of land cover changes in the region and provide valuable information to decision makers for improved tourism management and conservation strategies.  相似文献   
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