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101.
NDVI、NDMI与地表温度关系的对比研究   总被引:1,自引:2,他引:1  
通过研究归一化植被指数(NDVI)、归一化水汽指数(NDMI)与地表温度(LST)的相关关系,对比NDVI和NDMI定量分析LST的适宜程度。以Landsat 8遥感影像为数据源,以郑汴都市区为例,反演LST,计算NDVI和NDMI。从整体、分区、像元等不同层面分析NDVI和NDMI与LST的相关关系,并利用GEO-Da软件,分析150 m、300 m、450 m三种不同采样间隔数据的NDVI、NDMI与LST的空间相关性。主要结论为:①NDVI与LST的线性拟合度较差,而NDMI与LST具有很强的线性关系,剖面分析显示NDMI与LST呈显著负相关关系。②缓冲区分析结果表明,随着距城市中心距离的增加,用地类型增多,LST和NDMI之间的相关性逐渐增强。③在Moran's I空间相关性分析中,不同采样间隔下两指数与LST的负相关关系均比较明显,但由于水体在2个指数中数值的差异,使NDMI与LST表现出更强的空间负相关性,而NDVI与LST空间相关性则相对较弱。因此,总的来说NDMI是热环境研究的有效指标,与NDVI相比,NDMI与LST的负相关关系更强、更稳定,也更适宜于对LST的定量分析。  相似文献   
102.
This study focuses on the suburbanization and subcentering of population and examines the nature of spatial restructuring in terms of the population distribution in the Beijing metropolitan area.Instead of the classic density function approach,we employ the nonparametric analysis to characterize the spatial pattern of population densities in the Beijing metropolitan area and identify the suburban subcenters.Our findings suggest that the population has spread with rapid urban growth in the Beijing metropolitan area,and the compact urban form has been replaced by a more dispersed polycentric spatial distribution.However,compared with the decentralization of western cities,the spatial extent of the decentralization of population in the Beijing metropolitan area is quite limited.The rapid growth of population in the near suburbs has expedited the sprawl of the central city,with a larger central agglomeration of population dominating the metropolitan area.In this sense,the spatial pattern of the Beijing metropolitan area is still characterized by the continuous compactness.However,our findings do provide the evidence that the city has been turning to a polycentric structure.We find significant population subcenters have emerged in the suburbs of Beijing since the 1980s.But the polycentricity emerged in the Beijing metropolitan area is very different by nature from that observed in Western cities.The subcenters emerged are adherent to the development scheme planned for the city,so it can be referred to as the so called ’planned polycentricity’.  相似文献   
103.
Scholarly literature on newly incorporated municipalities (nims ) often focuses on why nims form. Instead of asking why nims formed, however, we ask why nims stopped forming. We first establish a temporal context for nims from 1950 to 2010, revealing an 86.2 percent decline in nim formation. The decline, triggered by stricter laws, smaller annexations, declining suburbanization, and boundary ossification, has profound implications for metropolitan fragmentation and public choice. We then establish a state‐level spatial context, revealing distinct high‐nim , low‐nim , and flux states due to boundary ossification, growth, and state/regional policy stimuli such as consolidation efforts, grants, and growth management provisions.  相似文献   
104.
"The aim of this paper is to utilise recently released census results to examine patterns of population change in non-metropolitan Australia during the 1986-91 period, focusing particularly upon the net migration component of that change. The paper presents an overview of recent trends in population change in non-metropolitan areas and then moves to an analysis of net migration patterns in non-metropolitan local government areas during the late 1980s using a Life Table Survival Ratio technique to estimate net migration. It appears that the trends observed in the early 1980s have continued into the late 1980s and early 1990s, and that overall the 'turnaround' is slowing down and becoming more diversified, more complex, and much less predictable in the 1990s."  相似文献   
105.
In this article, we develop a model for explaining spatial patterns in the distribution of households across metropolitan regions in the United States. First, we use housing consumption and residential mobility theories to construct a hypothetical probability distribution function for the consumption of housing services across three phases of household life span. We then hypothesize a second probability distribution function for the offering of housing services based on the distance from city center(s) at the metropolitan scale. Intersecting the two hypothetical probability functions, we develop a phase-based model for the distribution of households in US metropolitan regions. We argue that phase one households (young adults) are more likely to reside in central city locations, whereas phase two and three households are more likely to select suburban locations, due to their respective housing consumption behaviors. We provide empirical validation of our theoretical model with the data from the 2010 US Census for 35 large metropolitan regions.  相似文献   
106.
《Urban geography》2013,34(1):42-47
The paper compares density patterns of the three largest Canadian metropolitan regions with those of a sample of 12 U.S. urban areas with comparable populations. It verifies if such patterns support claims of Canadian urban distinctiveness prevalent within this country's research literature. Findings indicate that regional differences among U.S. cities are as important as cross-national distinctions. Measures of centrality and overall density place observed Canadian metropolitan areas within the same category as older U.S. East Coast metropolitan areas. Inter-city comparisons of historically and geographically defined zones suggest a period of cross-national convergence before World War II, when the inner city was developed, followed by a period of divergence from the 1940s to the 1970s, when the inner suburb was built. The development of the outer suburb, which began in the early 1970s, marks a return to cross-national convergence. These results question the continued relevance of the literature on the distinctiveness of Canadian urbanization.  相似文献   
107.
《Urban geography》2013,34(3):312-333
Since 1978, China has experienced rapid continuous urban transformation, and many mega-urban regions have stood out. But how to measure mega-urban region formation and to what extent they have formed in China, are still questions that have not been fully answered. Using census data by county, this study illustrates China's intensifying population concentration and region-based urban transition in 1990s. By 2000, three geographically continuous regional concentrations had formed in China —Beijing-Tianjin-Tangshan (Jing-Jin-Tang), the Yangzi River Delta (YRD), and the Pearl River Delta (PRD). All were characterized by region-based urban transition, with their "remote rural areas"3 involved in economic transformation; elsewhere, population agglomeration and urban transformation still focused mainly on major cities and their peripheral zones. It is the coexistence of great global attraction and severe local challenges in these mega-urban regions that makes them distinct from other metropolitan areas.  相似文献   
108.
唐鑫  龚绪龙  许书刚  张其琪  郭慧  邓峰丽 《地质论评》2021,67(6):67120013-67120013
地下空间资源是地表基质层中宝贵的自然资源之一,其作为城市有机体的重要组成部分,在未来城市建设中起着举足轻重的作用。苏南都市圈城市地下空间资源开发在全国处在领先地位,地下空间规划管理方面已形成较为完善的体系,城市地质调查也在全国率先实现全覆盖。依据地下空间资源开发现状和地质结构 “软硬”两个方面条件对苏南都市圈城市地下空间资源进行分类,划分为宁镇丘陵岗地型、苏锡常平原型和长江中下游冲积平原型三种类型。不同类型城市地下空间资源开发的地质背景和城市需求不尽相同,需根据实际情况定制不同的地下空间调查、规划、建设、管理体系。城市地下空间资源地质调查作为城市地质调查工作的延伸,需要提出更高的要求。本文从城市地下空间资源地质调查精度和深度、多参数多尺度一体化建模、地下空间资源评价、多种地下资源协同利用、地质资料信息数据库与平台建设等方面提出对策建议,用于指导未来城市地下空间资源调查的工程实践,为地质调查成果支撑城市地下空间全生命周期发展提供借鉴意义。  相似文献   
109.
彭文英  刘念北 《地理科学》2015,35(5):558-564
采用单项指标估测,分析了首都圈土地资源人口承载及其限制性,提出了人口空间分布优化策略。首都圈水资源及建设用地生态适宜量限制了人口承载能力,京津土地资源人口承载力已基本达到饱和,环京津的冀东、冀中地区承载潜力还较大,冀北地区应紧缩开发空间而拓展生态空间。首都圈土地资源开发利用及人口发展战略分区为:首都圈北部生态屏障建设区,人口限制发展;中部都市功能优化区,人口控制增长;东部人口产业沿海集聚区,人口鼓励增长;南部绿色空间优化区,人口适度增长。首都圈的健康发展,应实施差异化的土地利用及人口发展政策,整体提升人口承载力,并加大区域统筹力度,科学、合理地引导人口的空间分流和聚集。  相似文献   
110.
付明明 《地下水》2019,(3):142-144
为研究新疆喀什地区降水量中长期预测问题,结合ARIMA模型对新疆喀什地区的降水量进行预测,利用喀什地区两个子流域1950-2015年实测年降水数据分析其模型的适用性和预测精度。结果表明:ARIMA模型可较好的模拟喀什地区的年降水量,具有较好的预测精度,模拟降水量和实测降水量之间的误差相对值低于20%,绝对误差也可控制在15 mm以内;从空间角度分析,降水总体分布从东向西逐步递减,预测结果和实际降水空间分布状况较为吻合,可达到乙级精度标准。研究成果对于喀什地区中降水量长期预测具有较好的参考价值。  相似文献   
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