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131.
Even though diversified agroforestry systems can provide sustainable livelihoods and a resilient production of different goods, adoption remains limited in Bolivia. We examine major obstacles to agroforestry adoption and possible incentives proposed by farmers and civil-society organizations, and relate them to governance and international mechanisms that might play a role in agroforestry adoption. Market access for produce from diversified agroforestry remains difficult, as does its processing and transport. Moreover, farmers have difficulties in achieving the quantities and homogenous quality demanded by markets in the major cities. But most importantly, farmers and civil-society organizations saw little government support, although ‘ecological production in harmony with Mother Earth’ is prescribed by law and the constitution. Agroforestry farmers needed support most urgently in the initial phase, when investment costs are high and returns low. They suggested affordable credits, subsidies for diversified farming systems, and insurance against fire. We identified important albeit small steps towards developing markets for agroforestry products, but government support – mostly in the form of diesel subsidies, materials, and infrastructure – mainly benefitted large-scale monocultures and cattle ranching. In response to this, interviewees opted for strengthening farmers’ organizations, for demanding support with the help of civil-society organizations, and for disseminating best practices.  相似文献   
132.
20世纪以来,科学技术的快速发展,促进了全球经济的增长,给组织带来了发展的机遇,但是市场环境的剧烈动荡,使组织面临巨大的市场挑战和风险。组织为了生存,必须进行变革,但变革的高风险和高成本又反过来影响了组织生存。因此,组织变革与组织存活的关系是一个值得探讨的话题。目前,此问题的研究主要集中在两个视角:适应视角和生态学视角。其中,生态学视角是一种新的分析视角,为组织变革理论的研究提供了重要借鉴。  相似文献   
133.
[目的]研究全球气候变化背景下气候生产潜力的时空分布特征,对于合理利用农业气候资源,促进农业生产力的提高具有重要意义。[方法]选择1901—2000年哈萨克斯坦24个代表气象站点的月平均气温和降水资料,采用Thortwaite Memorial、Miami模型估算气候生产潜力,并运用气候倾向率、M-K检验以及ArcGIS空间插值等方法对气候生产潜力时空分布特征进行分析。[结果](1)1901—2000年哈萨克斯坦气候生产潜力总体表现为增长趋势,不同时段气候生产潜力差异明显,相对于其他研究时段(T1,T3),T2(1936—1970年)时段气候生产潜力及增长速率最大,并且水热匹配状况最好;(2)哈萨克斯坦气候生产潜力空间分布地域性明显。YP(降水生产潜力)和Y E(蒸散生产潜力)总体表现为自东南向西北递减的趋势,YT(气温生产潜力)表现为自西南向东北递减的趋势,气候生产潜力高值区主要位于天山北麓及东部山区的河谷地带,低值区位于西部和南部荒漠区;(3)气候生产潜力对降水更为敏感,当气温保持不变,降水量增加(减少)10%、20%,YE将增加(减少)9.6%、19.94%。[结论]哈萨克斯坦东部气候生产潜力大于西部,天山北麓及河谷地区气候生产潜力大于平原地区,哈萨克斯坦气候生产潜力主要受降水量的制约,未来“暖干型”变化将会使研究区气候生产潜力下降。为提高农业生产潜力,必须加强对农业基础设施的建设和提高水资源的调配能力。  相似文献   
134.
In recent years, numerous articles have addressed management strategies aimed at assisting forests to adapt to climate change. However, these seldom take into account the practical and economic implications of implementing these strategies, notably, supply of forest plants and seed. Using semi-structured interviews with practitioners involved in the plant and seed supply chain in Great Britain, we highlight a series of practical and economic bottlenecks commonly encountered in the supply of locally sourced seed and domestically produced planting stock for native woodland and hedging markets. We find that adoption of alternative seed sourcing strategies, designed specifically to account for directional climate warming, is likely to exacerbate existing problems by adding further complexity to decisions nurseries make about tree species and seed origins to produce. The lack of long-term market predictability brought about by the current configuration of forestry grants and regulations and, in particular, the administrative systems for processing grant applications is identified as a major impediment to having a sustainable and competitive supply of home-grown and currently adapted planting stock. Finally, the time and effort it takes to supply healthy plants for native woodland creation projects deserves much wider recognition throughout the industry and will be crucial if planting objectives are to be met sustainably.  相似文献   
135.
Shortfalls in global food production, coupled with the growing visibility of climate change's disruptive effects, have underlined for many observers the importance of devoting rural lands to their ‘optimal’ use, where they can make maximal contributions to the global imperatives of feeding the human population and maintaining vital environmental services. In this context observers have endorsed rural land use planning as a way to insure that, at least in theory, lands get devoted to their best uses. In practice, land use planning in the developing world has resembled ‘organized anarchy’. Small landholders with insecure land tenure, overseas investors seeking large land deals, NGOs representing indigenous peoples, government officials, and staff from international environmental NGOs and multilateral organizations have come together in strategic action fields to struggle over and sometimes negotiate land use plans for contested landscapes. These plans represent a strategic, spatially explicit response to the climate change–biodiversity–food security crisis.  相似文献   
136.
面对气候变化的机遇与挑战,中国政府已采取了一系列积极的政策和切实的行动,其中包括将于2017年启动全国性碳交易体系。研究首先对碳交易体系的国外研究作了简要概述,然后梳理了以欧盟碳交易体系为首的10个国外碳交易体系和中国7个省市的碳交易试点的实践。研究最后对全国碳交易体系的建立提出了几点思考,强调了数据的科学监测和林业碳汇在中国碳交易体系中的重要作用。  相似文献   
137.
The conservation and management of protected areas in urban settings has become increasingly challenging with dynamics over land use change in adjacent urban areas being highly relevant to, but at times conflicting with, the protected area. This study seeks to better understand the implications of land use change processes to urban protected area management through the case study of the Las Piñas – Parañaque Critical Habitat and Ecotourism Area (LPPCHEA) in Metro Manila, Philippines. Factors and processes influencing land use change and protected area management and the impact of stakeholders’ perceptions on protected area were analyzed. The urban protected area in itself has limited influence on its surrounding urban areas, as land use change in these areas is shaped more by social, economic and policy/institutional factors occurring within the context of urban-regional development. The study also found that land use conflict is evident in an urban protected area due to the competing ecosystem services derived by various stakeholders. This discord is deepened by the lack of coordination between land use planning and protected area management. Integrating protected area management with land use planning through legally binding instruments, specific timeframes and clear internal procedures can help resolve land use conflict for an urban protected area at the strategic or policy level.  相似文献   
138.
The systemic change of 1989/1990 is usually identified as the critical juncture in the modern economic history of post-communist economies. While the change itself was indeed a remarkable moment in time, a branching point from which a multitude of new paths originated in most of the countries in Central and Eastern Europe, this was only partially true in the case of Hungary. If a critical juncture is sought for Hungary, it is more likely to be 1968, the year the New Economic Mechanism was launched. By applying the conceptual framework of historical institutionalism, the article argues that what made Hungary unique during the communist era and what rendered its position as a (one-time) frontrunner proved to be a serious constraint after the systemic change. The legacy of a pre-born welfare state, the constant need for compensating potential losers of any economic reform, along with short-sighted decision-making, have together generated specific path dependencies in the Hungarian trajectory of economic development.  相似文献   
139.
Research summary> : W e take a microfoundational approach to understanding the origin of heterogeneity in firms' capacity to adapt to technological change. We develop a computational model of individual‐level learning in an organizational setting characterized by interdependence and ambiguity. The model leads to organizational outcomes with the canonical properties of routines: constancy, efficacy, and organizational memory. At the same time, the process generating these outcomes also produces heterogeneity in firms' adaptive capacity to different types of technological change. An implication is that exploration policy in the formative period of routine development can influence a firm's capacity to adapt to change in maturity. This points to a host of strategic trade‐offs, not only between performance and adaptive capacity, but also between adaptive capacities to different forms of change . Managerial summary : W hy are firms differentially effective at adapting to technological change? We argue that firms differ in the adaptive capacity of the routines that underlie their capabilities. These differences arise well before change occurs, and result because firms build routines that are differentially responsive to signals of performance decline associated with technological change. Thus, early managerial efforts to build superior productive efficiency must be complemented by efforts to build superior adaptive capacity. Our theory suggests that managers can prepare for technological change by implementing policies, in the formative period of organizational development, that promote individuals' exploration of novel actions. However, there are trade‐offs because preparation aimed at building adaptive capacity to one type of technological change may limit adaptive capacity to other types of change . Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
140.
论历史逻辑     
历史逻辑是以历史时间的历时性和共时性统一为基础的概念推论,研究关于叙述史中基本概念之间的意义关系和推论规则。过去、现在和未来是历史逻辑的基本范畴,“过去-现在-未来”三段式是历史逻辑的基本公式,它是概念逻辑推论三段式“正题-反题-合题”在历史逻辑中的具体形式。历史逻辑研究的目的,是根据特定历史时段的特殊性,建构以不同时段概念为逻辑变项的历史逻辑,预见未来的发展,规划现在的实践。  相似文献   
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