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131.
山洪灾害具有广泛性、突发性、破坏性等特征,开展山洪易发区的社区韧性评估,从而提高灾害应对能力是当前防灾减灾的前沿热点和难点。论文提出了一套多学科的综合方法:① 利用中介效应明晰了山洪视角下社区韧性评价体系各指标间的定量化传递关系;② 构建了基于决策实验室分析和解释结构模型的耦合数学模型,确定社区韧性影响因素的多级递阶解释结构模型,分析社区韧性的差异化影响因素;③ 采用信息扩散方法,定量分析山洪灾害社区韧性的变化趋势并排序。以粤北山洪易发区为例,从城镇、村落、城乡结合部3种类型社区进行灾害韧性分析。结果表明:山洪视角下的社区韧性指标体系是一个多维度多层次的复杂网络系统,包括环境、社会、心理、制度和信息沟通5个方面;不同类型社区灾害韧性的直接影响因素呈差异化特征,而供排水设施建设和洪灾应急演练为社区韧性的根本影响因素,对增强山洪视角下社区韧性发挥本质性作用;由于调研村落多位于山洪频发区,居民防范灾害、减轻灾害影响的意识较强,村落较城镇和城乡结合社区呈现出更高的韧性。研究可为提升粤北山洪易发区社区韧性及社区防灾减灾能力提供科学参考,该综合分析方法亦可为其他类型灾害的精细化防灾减灾提供支持。  相似文献   
132.
In the context of disaster normalization, the concept of “resilience” has been gradually introduced into the field of disaster prevention and mitigation in urban communities. In order to resist the increasingly frequent disasters caused by extreme weather, it is necessary to shift the focus of building resilient urban communities to the level of stormwater management. Community resilience is a disaster prevention and mitigation capability based on community resources. In order to solve the deficiency of storm and flood management in the current construction of resilient communities in China, it is necessary to establish a quantitative evaluation system to evaluate it. This paper uses the analytic hierarchy process and Delphi method to establish a community resilience evaluation system from the perspectives of community material space level, community management level and individual level. Then three communities in Hefei City, Anhui Province are selected for practical application of the system, and corresponding optimization and transformation strategies are proposed. The results show that: (1) The resilience of community stormwater management is closely related to the integrated environment of the community, the allocation of flood control facilities and the daily disaster prevention and mitigation management; (2) The ability of disaster prevention and mitigation and the awareness of public participation of the residents in all communities are relatively weak, and the communities invest less in the popularization of stormwater management wisdom; and (3) Resilient communities should not only pay attention to the construction of non-engineering disaster prevention measures, but also to the application of small-scale green infrastructure oriented toward stormwater management.  相似文献   
133.
Grasslands have critically important ecological and economic values while most of them have been suffering from various degrees of degradation in China due to overgrazing. The “Forage-Livestock Balance” (FLB) policy has been implemented for more than a decade, aims to balance the relationship between forage productivity and grazing consumption of grasslands by livestock. According to the review of statistical data and literatures on policy evaluation, FLB-dominated subsidies for grassland ecological conservation policies are ineffective on grassland restoration, livestock reduction in some overloaded areas and improvement on herdsmen livelihood. To deal with the dilemma, we suggest a fundamental shift of strategy from controlling livestock numbers to maintaining and improving grassland health (MIGH) based on ecological theories, and promote the sustainable development of grassland in China. The results show that, FLB policy failed to obtain expected benefits mainly because it interfered with the herders' autonomous use of contracted grasslands along with the defects of its underlying theory and methodologies. Implementing reward and punishment based on ecosystem health will not only motivate herders to manage their grassland autonomously, but also be more scientific and feasible than FLB.  相似文献   
134.
中国地级及以上城市网络结构韧性测度   总被引:4,自引:1,他引:4  
魏石梅  潘竟虎 《地理学报》2021,76(6):1394-1407
随着城市间关系趋向于网络化发展以及外部急性冲击和慢性压力的增加,城市网络结构韧性作为衡量区域韧性的重要手段,致力于评估城市网络系统在面对突发故障或扰动时,能够抵御、吸收和恢复原有网络特征和重要功能的能力。以中国346个地级及以上城市为研究对象,采用2017年百度指数、腾讯人口迁徙大数据等,在构建信息、交通、经济和综合城市联系网络的基础上,从城市节点和网络层面对其层级性和匹配性进行测度,并对中断场景下网络的传输性和多样性进行分析,进而针对各网络从不同视角提出网络结构优化策略和建议。结果表明:① 2017年中国346个地级及以上城市的信息、交通、经济和综合联系网络整体上呈现以“胡焕庸线”为界的“东密西疏”的分布格局,但空间结构各有特点。② 信息、交通和经济三大网络的层级性排名依次为经济>信息>交通网络。大城市及省会城市因其信息技术的快速创新与传播、产业经济的高度发展与集聚及交通基础设施的快速配备与完善在网络中具有更高的层级。③ 信息、交通、经济三大网络均具有异配性特征。信息网络中高权重节点与低权重节点间的跨区域交流机会更多,因而具有最高的异配韧性。④ 信息网络的传输与多样韧性稍高于经济网络,远高于交通网络。同一城市节点的故障或中断在影响网络传输性的同时,也会累及网络的多样性。  相似文献   
135.
Ethnic minority populations in Yunnan have had diverse mobility patterns since the advent of globalized production and developmental programmes. The article presents insights into the various mobility patterns and their effects in Yunnan and contributes to an understanding of the present economic and social processes of mobilities and changes in China as a whole. The analysis is based on an empirical study conducted in the years 2010–2011 by the authors together with local researchers in Yunnan. The results revealed that the mobilities practised among members of the ethnic minority groups in Yunnan included not only outmigration but also cross-border cultivation of plantations, daily and circular mobility, inflows of labour and investors, and involuntary relocation. Although some mobilities may have been conducive to livelihoods and capabilities due to the income-earning and profit-making opportunities arising from the acquisition and appropriation of land and capital, they have also resulted in differentiation processes that confirm the counter-geographies of production, survival, and profit-making. The authors conclude that mobilities do not just concern physical location, but as a social process, mobilities have reconstituted relational references and networks in terms of ethnic and cultural identity, gender relations, labour division, and locality and community integration.  相似文献   
136.
《水文科学杂志》2012,57(1):12-20
ABSTRACT

What implications do societies’ risk perceptions have for flood losses? This study uses a stylized, socio-hydrological model to simulate the mutual feedbacks between human societies and flood events. It integrates hydrological modelling with cultural theory and proposes four ideal types of society that reflect existing dominant risk perception and management: risk neglecting, risk monitoring, risk downplaying and risk controlling societies. We explore the consequent trajectories of flood risk generated by the interactions between floods and people for these ideal types of society over time. The results suggest that flood losses are substantially reduced when awareness-raising attitudes are promoted through inclusive, participatory approaches in the community. In contrast, societies that rely on top-down hierarchies and structural measures to protect settlements on floodplains may still suffer significant losses during extreme events. This study illustrates how predictions formed through social science theories can be applied and tested in hydrological modelling.  相似文献   
137.
尚海洋  苏芳 《冰川冻土》2012,34(4):983-989
随着生态补偿研究的不断深入与生态补偿工程的广泛实施, 提高了人们对于环境问题的认识, 遏制了生态脆弱地区环境的进一步退化.实施生态补偿的环境保护作用显而易见, 不乏论述, 但对于改善农户生计水平, 提高生计资本的效用却鲜有论及.从农户生计入手, 评估农户的生计资本, 量化实施生态补偿对农户生计资本的影响, 分析生态补偿方式对农户生计资本的影响作用, 有利于揭示与评估生态补偿实施的有效性.对于地处黑河流域中游地区的张掖市来讲, 可以通过提高人力资本、 物质资本和金融资本的水平, 从而整体上提高农户的生计资本水平. 政策支持和资金支持两种补偿方式被多数农户作为首先的补偿方式, 而将物质支持作为首先的补偿方式人数较少; 技术补偿和物质补偿对物质资本、 物质补偿和政策补偿对社会资本显著, 且对于各生计资本的组份有正向拉动作用. 此外, 尝试分析了对各种补偿方式对生计资本拉动作用原因的推断.  相似文献   
138.
针对甘南黄河水源补给区实施的退牧还草工程, 基于"可持续生计框架", 建立生计资本指标, 利用农户调查资料, 测算生态补偿前后农户的生计资本, 采用均值比较分析和协方差分析评估生态补偿对农户生计资本的影响, 最后提出应建立多样化、差别化的补偿方式, 来提高不同地区农户的生计资本. 结果表明: 与退牧前相比, 农户的生计总资本显著增加, 由退牧前的0.216增至目前的0.277, 其中人力资本、物质资本、金融资本、社会资本分别增加了0.094、0.075、0.115、0.040, 自然资本显著下降, 降低了0.023. 生态补偿对农户生计资本结构的影响具有区域差异性, 生计资本总指数增幅最大的是半农半牧区, 依次是农区、纯牧区; 生态补偿对农户各生计资本关系的影响具有区域差异性, 实施生态补偿后纯牧区农户各生计资本之间的相关程度增强, 而半农半牧区和农区农户各生计资本之间的相关程度减弱.  相似文献   
139.
国外弹性城市研究述评   总被引:17,自引:1,他引:16  
蔡建明  郭华  汪德根 《地理科学进展》2012,31(10):1245-1255
城市如何在重重挑战与危机中, 因应各种变化, 保持自身发展活力, 是一个亟待解决的重要问题。本文梳理了国外弹性理论研究的4 个领域, 即生态弹性、工程弹性、经济弹性和社会弹性, 并归纳总结了它们各自的基本概念、内涵及代表性研究学者;在此基础上, 系统评述了国外相应的弹性城市研究的4 个领域的内涵与研究重点, 包括城市生态弹性、城市工程弹性、城市经济弹性和城市社会弹性;同时根据已有研究的发展脉络, 前瞻了未来弹性城市研究3 个趋势方向, 即社会平等的议题如何渗入到弹性城市的理念之中, 技术革新如何增强城市弹性, 跨学科、多领域的介入如何共同协作建设弹性城市。鉴于中国各地区自然社会经济差异较大, 不同地区的发展历史、发展阶段、社会文化背景不同, 因此弹性城市理论的应用更应考虑到中国特色, 使弹性理论本身更为“弹性”。  相似文献   
140.
生态系统恢复力研究进展综述   总被引:18,自引:3,他引:15  
气候变化和人类活动等致使全球生态系统发生了巨大变化,导致区域乃至全球生态系统恢复力不断下降, 成为胁迫生态系统可持续发展能力因素之一。如何维持生态系统的可持续发展能力,降低不确定性因素导致的问题已引起学术界及社会各界的高度重视。生态系统恢复力理论为解决这些问题提供了思路,生态系统恢复力提供了缓解生态系统状态转化的途径。虽然恢复力这一概念的管理价值已被接受和认可,但恢复力研究仍停留在概念层面及案例分析的模式上。目前生态系统恢复力研究尚缺乏科学统一的定义,且多为理论性分析而定量测度相对较少,生态系统恢复力的测定成为进一步探讨恢复力的重要步骤和切入点。本文通过回顾生态系统恢复力概念发展进程,概述关于恢复力概念的观点和恢复力的内涵与属性,描述目前恢复力的主要理论基础,论述目前研究者对恢复力测量的尝试;总结了相关研究中发现的影响生态系统恢复力的关键因素及其影响机制,进而提出了目前生态系统恢复力研究方面亟待加大研究力度的方向。  相似文献   
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