首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   712篇
  免费   36篇
  国内免费   2篇
财政金融   13篇
工业经济   20篇
计划管理   75篇
经济学   234篇
综合类   26篇
运输经济   1篇
旅游经济   14篇
贸易经济   65篇
农业经济   237篇
经济概况   65篇
  2024年   4篇
  2023年   18篇
  2022年   35篇
  2021年   32篇
  2020年   66篇
  2019年   36篇
  2018年   24篇
  2017年   21篇
  2016年   32篇
  2015年   28篇
  2014年   28篇
  2013年   38篇
  2012年   35篇
  2011年   42篇
  2010年   45篇
  2009年   26篇
  2008年   62篇
  2007年   48篇
  2006年   44篇
  2005年   31篇
  2004年   13篇
  2003年   15篇
  2002年   5篇
  2001年   3篇
  2000年   5篇
  1999年   3篇
  1998年   1篇
  1997年   2篇
  1996年   1篇
  1995年   1篇
  1994年   2篇
  1993年   2篇
  1992年   1篇
  1983年   1篇
排序方式: 共有750条查询结果,搜索用时 31 毫秒
1.
江西省农村土地利用变化及生态系统服务价值研究   总被引:2,自引:0,他引:2  
[目的]土地利用变化及生态系统服务价值研究一直是土地资源评价与管理方面的热点研究问题,通过对江西省土地利用变化和生态系统价值进行研究,为江西省土地规划和资源的可持续利用提供理论依据。[方法]文章基于文献查阅的方法,利用多样性指数模型、土地利用动态度和生态系统服务价值模型,结合2009~2016年江西省农村土地利用的现状及变化,分析了其生态系统服务价值及相应变化。[结果]近年来,江西省农村土地利用程度高、多样性指数中等且呈先下降后上升的趋势。土地利用类型的面积与该土地利用类型的生态系统服务价值呈同向变化的关系。通过对土地利用类型的ESV值进行分析,发现农村土地利用的生态系统服务功能价值总体在减少;对单项生态系统价值分析,水源涵养在江西省农村土地生态系统服务中占有最重要的地位。[结论]2009~2016年江西省农村土地利用结构都发生了变化,生态系统服务总价值出现了降低趋势,各单项生态系统服务功能价值也在减少,土地利用结构对生态系统功能价值具有决定作用。因此,政府应该合理利用土地,保护生态系统,协调好环境与经济发展的关系。  相似文献   
2.
当前企业推进绿色转型进程、提升企业绩效,是实现高质量发展的重要途径。鉴于企业主动应对内外部因素联动影响的重要性,以动态能力理论视角,在探讨了企业变革发展驱动机制的基础上,尝试构建动态环境规制嵌入下的战略柔性与企业绩效的理论框架。分析并实证检验了战略柔性对企业绩效以及差异化强度的动态环境规制在二者关系中调节效应的作用机理和边界。研究结果显示,当前情境下,前瞻柔性、响应柔性对企业绩效均有显著的正向影响,且响应柔性的贡献度较高;两者交互效应亦能显著的正向影响企业绩效;表明企业对环境变化的预测、反应能力以及将两者协同配合是绿色转型发展的重要措施。一般强度的动态环境规制在前瞻柔性、响应柔性与企业绩效的关系中均不起显著的调节效应;高强度动态环境规制仅在响应柔性和企业绩效的关系中起显著负向调节效应;表明动态环境下,一般强度的政府规制政策对企业的决策和创新等行为更多的是无显著影响,充分尊重其自主发展;同时政府要根据环境变化,合理控制环境规制实施强度,谨防给企业应对环境冲击造成额外的负担。综合研究结果,提出企业加强多重柔性机制建设的力度和政府注重环境规制政策引导作用的策略,最终实现各利益相关者协同推进高质量发展的目标。  相似文献   
3.
苏南乡村地区一直是中国乡村建设的先行区域,特殊的纵横交错的水网结构构成了一个错综复杂的系统,呈现出其他地区不具有的复杂性和生态特殊性。随着城镇的扩张,乡村的发展建设使其水网空间的平衡发展面临极大的挑战。传统单一静态的规划方法逐渐显示出无法适应经济、社会等发展要求的缺陷。苏南乡村地区以水为核心,从水生态系统服务供需关系的视角下探究水网乡村的适应性规划策略更加适应当前的乡村现状和需求。以传统水网乡村空间形态转译为基础,建立水生态系统供需服务评估体系,在评估水生态系统服务供需能力的基础上,分析供需分异模式及供需矛盾。从构建乡村水域空间生态格局、乡村水域空间功能分区规划,以及乡村水域空间多情景预判3个方面,提出苏南水网乡村的适应性规划策略,并为水网乡村的生态实践提出新思路。  相似文献   
4.
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   
5.
[目的]恶劣的生态环境和有限的资源驱动着新疆特殊生态系统服务的形成,人类又通过对生态系统服务的消费来满足和提高自身福祉,需要研究其时空变化并辨识主要驱动因素,支持区域可持续发展。[方法]文章构建了融合不同土地利用类型生态系统服务的价值量排序及服务功能强度矩阵的生态系统服务评估体系,并耦合3种关键驱动因子以评估各个因子的驱动强度,实现对生态系统服务热点与冷点变化的驱动及迁移分析。[结果]2000—2010年全疆生态系统服务总体增加,这一时期生态系统服务的热点区大部分转变为2010—2015年的冷点区,且15年来生态系统服务总体呈现小幅下降趋势。3个时期北疆和南疆人为干扰强度均呈增加趋势,由其驱动的生态系统服务则相应减小;南疆地区植被覆盖范围极其有限,故对生态系统服务驱动强度低;降水在北疆和南疆都能够产生高生态系统服务,但降水量的不稳定性能够使生态系统服务产生较大波动。相比于南疆地区,北疆生态系统在外界干扰下能够体现出更强的抗性和整体性,从而实现相对高效的生态系统服务输出。[结论]对关键驱动因子作用下的生态系统服务进行时空变化分析,有助于理解当地生态系统产生变化的原因,从而为当地生态环境保护提供参考。  相似文献   
6.
Advances in the study of both markets and platforms contribute to economics. Platforms are typically digital markets, although platforms can designate markets generally. So, the economics of markets and the economics of platforms are one and the same. Platforms show the critical role of intermediaries in endogenous price adjustment and market clearing. The platform model remedies problems with general equilibrium analysis by combining and extending the basic Walrasian and Marshalian market models. The analysis of platforms provides explanations for the bid–ask spread, including market power, search costs, matching costs, adverse selection, and moral hazard. The study of platforms demonstrates the importance of participation and coordination in the formation of markets. The discussion emphasizes that platforms have significant implications for the theory of the firm. The analysis further considers how platforms affect innovation and entrepreneurship.  相似文献   
7.
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   
8.
Creative hotspots have become a key driver for urban policies to stimulate social, cultural, environmental and organisational growth of creative and knowledge-based clusters, districts and hubs. However, their functional and spatial characteristics vary due to their different evolving structure as new spaces of economic activity in different contexts. This article points to a consideration of new foci for both land use and urban economic policy through a mapping of formal and informal creative hotspots in Brisbane, Australia. The study found two distinctive development patterns: (a) earlier top-down approaches as instigated by national and international innovation policies, and; (b) recently emerging bottom-up spaces for creativity, knowledge and innovation practices. This study examines how formal creative strategies and emerging informal creative spaces shape cities and urban policies. The methodology comprises online data collection and a review of creative and knowledge strategies and implementation policies. Data was then analysed via multiple mapping techniques illustrating the spatial distribution of creative hotspots, formal and informal formations, scale and land use characteristics. The research findings consolidate our understanding of Brisbane’s creative ecosystem and suggest new urban policy mechanisms to better foster the interrelationship between top-down and bottom-up approaches in cities, that is, between formally planned and large-scale interventions and small-scale organic and informal creative activities.  相似文献   
9.
Many developing countries face a major challenge today: how to safeguard the biodiversity maintained in the fields of the rural poor - which constitute a national and global public good - whilst meeting those same people's development needs and rights? A solution to this dilemma has thus been sought in adapting the design and implementation of Payments for Ecosystem Services (PES) concepts to the conservation of agrobiodiversity.Here we review the application of nine such Payments for Agrobiodiversity Conservation (PACS) schemes that have been applied to date in four Latin American countries over the period 2010–2018. These covered 130 threatened varieties across a number of major food crops, and involved over 100 farming communities and 1,100 farmers (45 % of which were women). Conservation service offers were received through a competitive tender mechanism. Average bid offers revealed high heterogeneity, varying between US$675/ha. to ten times as much.In relation to issues identified as key to PES, such as spatial targeting, differentiated payments and conditionality, the underlying design of the PACS schemes may be considered solid. PACS-related prioritisation processes allow for the a priori identification of sites with high ecosystem service densities and high threat levels. The use of competitive tenders permits accounting for cost heterogeneity in the provision of conservation services and for payments to be differentiated. Conditionality is strong.In terms of implementation, a “back of the envelope” calculation based on the results of the competitive tenders suggests that conservation costs are modest. For a priority conservation portfolio of 100 varieties (which may be from different crops) each with a target area of five hectares, costs would amount to just under US$860,000 over twenty years or US$70,000 p.a. at a 5 % discount rate. The small-scale and one-off nature of the interventions realised to date, along with threatened crop variety seed availability constraints, have however meant that environmental effectiveness has been incomplete in the short-term (area cultivated with specific threatened varieties increased, but still below the “not at risk” threshold). The establishment of systematic monitoring systems is required to determine longer-term impacts and inform more regular PACS interventions within a dynamically evolving systems context.  相似文献   
10.
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号