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81.
通过估计中国农村居民收入分配的lorenz曲线测算了2006、2007年中国农村贫困和收入不平等的状况,并运用shapley分解法对贫困指数的变动进行分解,分析物价水平、经济增长、收入分配对贫困变化的影响。研究结果表明:(1)2007年农村贫困发生率较2006年有所下降,但下降速度比较缓慢;(2)农村居民的收入差距逐渐在拉大,收入不平等程度有所加重;(3)经济增长减缓了农村贫困,但由于物价水平的上涨和收入分配的恶化,贫困人口整体的贫困状况不轻反重。  相似文献   
82.
In recent decades, human activities have significantly affected coastline changes with the dramatic expansion of coastal cities. In this study the modified normalized difference water index was applied to multi-temporal images of Shenzhen to determine coastlines, and a point-based approach was used to reflect spatial location changes from 1988 to 2015. The results of the stepwise discriminant analytical method and the grey correlation analysis model suggest that socio-economic factors have greatly affected changes in the coastline stability and types. It can be concluded that the population growth factor is responsible for coastline changes, in addition to some economic factors.  相似文献   
83.
随着经济体制的转变,经济的转型已成为促进发展中国家城市发展的重要因素。为了解城乡地域结构的转变特点和影响因素,本研究多角度量化了宁波市城乡结构的发展与经济转型的关系。提出量化城乡地域结构的指标体系:土地利用面积与景观格局的变化,并提出衡量经济转轨的角度:全球化、去行政化以及市场化。结果表明:城市地区受市场化和行政分权政策影响,整体景观格局趋于破碎化、不规则化。乡村地区由于财政分权,整体格局呈现破碎化和单一化。城市建筑用地扩张受市场化和全球化影响,农田的减少与市场化政策有关。本研究得到了不同城市规划区域对经济转型的响应形式,为政策制定提供建议。  相似文献   
84.
本文根据近年来在历史气候变化和人类社会经济发展领域中因果关系的实证研究,特别是综合现有的定量研究成果,分析了历史上气候变化与人类社会经济发展的联系。结果表明,气候变化在最终和基本层面影响着社会经济发展。而且无论是长期还是短期的数据分析,气候短期波动或长期变化都会在社会经济发展中有所反映。从理论和方法学两个方面,这些研究成果促进了对气候变化影响下人类社会经济发展的认识,在全世界范围内都有学术借鉴意义和政策指导价值。  相似文献   
85.
1IN TR O D U C TIO NA s old as hum anity itself, land use change has runthrough the w hole history ofhum an existence and evo-lution. This change has not only objectively recordedthe space patterns of the earth surface changed by hu-m ankind,but also redi…  相似文献   
86.
In recent years, through the availability of remotely sensed data and other national datasets, it has become possible to conduct national-scale flood risk assessment in England and Wales. The results of this type of risk analysis can be used to inform policy-making and prioritisation of resources for flood management. It can form the starting point for more detailed strategic and local-scale flood risk assessments. The national-scale risk assessment methodology outlined in this paper makes use of information on the location, standard of protection and condition of flood defences in England and Wales, together with datasets of floodplain extent, topography, occupancy and asset values. The flood risk assessment was applied to all of England and Wales in 2002 at which point the expected annual damage from flooding was estimated to be approximately £1 billion. This figure is comparable with records of recent flood damage. The methodology has subsequently been applied to examine the effects of climate and socio-economic change 50 and 80 years in the future. The analysis predicts increasing flood risk unless current flood management policies, practices and investment levels are changed – up to 20-fold increase in real terms economic risk by the 2080s in the scenario with highest economic growth. The increase is attributable primarily to a combination of climate change (in particular sea level rise and increasing precipitation in parts of the UK) and increasing economic vulnerability.  相似文献   
87.
Australia's large regional cities and towns display a wide variation in their adjustment to the socio-economic transitions that have occurred over the past decade. In terms of socio-economic advantage and disadvantage, these changes, often associated with globalisation, wider economic and technological restructuring, the changing demographics of the population and shifts in public policy, are not evenly dispersed across non-metropolitan regions. Such outcomes have been discussed across a variety of academic disciplines using a variety of data and methods, and the research undertaken has provided a useful grounding for contemporary studies both theoretically and methodologically. Analysis of new data provides an opportunity to extend and update our understanding. This paper presents an analysis of secondary data aimed at analysing non-metropolitan cities, towns and regions based on differential levels of socio-economic performance. Using an alternative clustering method, this paper groups non-metropolitan cities, towns and regions according to the degree to which they share similar socio-economic and demographic outcomes. These clusters form the basis of a typology representing the range of socio-economic and demographic outcomes at the non-metropolitan level.  相似文献   
88.
长江上游侵蚀产沙与社会经济因子的关系   总被引:4,自引:0,他引:4  
近年来,随着一系列水利水保工程的建设和使用,长江上游地区人类活动改变泥沙过程的作用越发明显,有必要对其地位和作用进行宏观层面的分析。以四川省和重庆市为例,利用2007 年和1989 年县域截面数据研究了长江上游侵蚀产沙与社会经济因子的关系,结果表明:人口密度、耕地面积与侵蚀产沙具有显著的相关性,其中人口密度与侵蚀产沙的联系更为紧密,并且存在一个临界区间,当人口密度超过这个临界,侵蚀产沙随着人口密度与耕地面积的增加而减少;反之,则侵蚀产沙随着人口密度的增加而增加。这种临界现象实质上体现了地形、降水、土壤等自然环境对产沙的影响,也有部分人为作用。从时空变化来看,人口在不断的向产沙较少、自然条件良好的地区集中,从产沙较多、不适宜生产生活的地区迁离。自然因子对东部高人口密度地区产沙影响较小,对西部低人口密度地区的影响较大。总体上,自然因子对长江上游产沙格局的影响占主导。  相似文献   
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