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951.
Poverty at the national and sub-national level is commonly mapped on the basis of household surveys. Typical poverty metrics like the head count index are not able to identify its underlaying factors, particularly in rural economies based on subsistence agriculture. This paper relates agro-ecological marginality identified from regional and global datasets including remote sensing products like the normalized difference vegetation index (NDVI) and rainfall to rural agricultural production and food consumption in Burkina Faso. The objective is to analyze poverty patterns and to generate a fine resolution poverty map at the national scale. We compose a new indicator from a range of welfare indicators quantified from Georeferenced household surveys, indicating a spatially varying set of welfare and poverty states of rural communities. Next, a local spatial regression is used to relate each welfare and poverty state to the agro-ecological marginality. Our results show strong spatial dependency of welfare and poverty states over agro-ecological marginality in heterogeneous regions, indicating that environmental factors affect living conditions in rural communities. The agro-ecological stress and related marginality vary locally between rural communities within each region. About 58% variance in the welfare indicator is explained by the factors of rural agricultural production and 42% is explained by the factor of food consumption. We found that the spatially explicit approach based on multi-temporal remote sensing products effectively summarizes information on poverty and facilitates further interpretation of the newly developed welfare indicator. The proposed method was validated with poverty incidence obtained from national surveys. 相似文献
952.
提升金融服务实体经济效率是海南自贸港建设亟待研究和突破的“靶点”。论文通过测算2011—2020年海南自贸港18市县金融服务实体经济效率,利用Dagum基尼系数与Kernel密度估计方法刻画效率的时空异质性,并借助随机森林模型揭示其驱动机理,创新性地从时空视角挖掘海南自贸港金融服务实体经济效率分异机制。研究发现:(1)海南自贸港金融服务实体经济效率时空非平衡性明显,时序上阶段性显著,空间上呈西高东低、高值聚集、中部“洼地”的分布特征,西北部市县与中部市县各自逐步形成高值、低值聚集区;(2)总体及沿海市县梯度分化特征逐步加强,而非沿海市县内部差距则逐步缩小,沿海区域金融服务实体经济效率的空间分异是总体分异的主要来源;(3)政府干预是效率分化的主导因素,含金融集聚度在内的影响因素对效率均呈非线性影响且作用趋势与阈值各异,各因素的边际产出能力及各市县对要素的吸收与应用能力的动态差异是时空异质性的主要来源。研究结论可为优化海南自贸港金融资源的空间配置、提升金融服务实体经济效率提供科学依据。 相似文献
953.
Mario Cardozo 《The Professional geographer》2013,65(3):443-446
Web 2.0 has yielded a wealth of publicly available data, largely through the popularization of social media and the proliferation of user-generated content (UGC). Thus, the data void in social science research is diminishing as these new data sources are exploited. The discipline of geography, in particular, stands to benefit considerably from geotagged UGC or volunteered geographic information (VGI). In this article, we utilize a form of UGC—restaurant reviews—to evaluate the geography of Web 2.0 in Franklin County, Ohio. We find that restaurant reviews are largely concentrated in relatively few areas of the city, indicating that the impacts of Web 2.0 have not touched down evenly within the central county of the Columbus metropolitan statistical area. We argue that an intraurban digital divide is still apparent and might even be exacerbated by Web 2.0. 相似文献
954.
Karen M. Morin 《The Professional geographer》2013,65(4):534-543
This article explores the “unpopular” archived life of Charles P. Daly, thirty-five-year president (1864–1899) of the New York–based American Geographical Society. This one-time highly prominent judge and civic leader popularized geography among professionals and the public alike. Daly's popular geography, along with his subsequent containment within the archives, suggests explanations for his dismissal among geographical audiences of today. It is a useful and necessary exercise to trace the neglect of Daly within histories of geography and recapture him for today's audiences, not only because of his influence on post–Civil War American geography but also because his story can shed light on how “disciplinary remembering” functions in geography. 相似文献
955.
Karl S. Zimmerer 《The Professional geographer》2013,65(3):335-356
The global shift to small- and medium-scale irrigation is potentially compatible with high-agrobiodiversity production. A case study of the Cochabamba region in central Bolivia between 1990 and 2002 is designed to examine new interactions of irrigation with agrobiodiversity through change and continuity of landscape structures and functions. Irrigation change contributed to increased commercial potato and peach farming. Still persistent interactions of canal woodland habitat (landscape matrix including uncultivated or “wild” agrobiodiversity) with patches of cultivated agrobiodiversity helped ensure nutrient transfer and likelihood of gene flow. Farmers' field-level responses continued to include agrobiodiversity, especially multiple farmer varieties (FVs) of Andean maize. Capacities of social–ecological resilience in the period from 1990 to 2002 are estimated to have been moderate in anthropogenic canal woodlands (> 95 percent continued cover, albeit with reduced connectivity) and cultivated agrobiodiversity (viable with local loss of Andean potato FVs) and moderate-high in wild agrobiodiversity (viable with reduced capacity due to modified weed management). Indigenous “ethnodevelopment” applied to Andean community irrigation contributed positively to social–ecological resilience, albeit with significant limitations. Findings recommend that global change policies build emphasis on the interactions of water resource and agrobiodiversity management. 相似文献
956.
Max Lu 《The Professional geographer》2013,65(3):466-468
Landing a rescue helicopter in a wilderness environment, such as Yosemite National Park, requires suitable areas that are flat, devoid of tree canopy, and not within close proximity to other hazards. The objective of this study was to identify helicopter landing areas that are most likely to exist based on available geographic data using two GIScience methods. The first approach produced an expert model that was derived from predefined feature constraints based on existing knowledge of helicopter landing area requirements (weighted overlay algorithm). The second model is derived using a machine learning technique (maximum entropy algorithm, Maxent) that derives feature constraints from existing presence-only points; that is, geographic one-class data. Both models yielded similar output and successfully classified test coordinates, but Maxent was more efficient and required no user-defined weighting that is typically subject to human bias or disagreement. The pros and cons of each approach are discussed and the comparison reveals important considerations for a variety of future land suitability studies, including ecological niche modeling. The conclusion is that the two approaches complement each other. Overall, we produced an effective geographic information system product to support the identification of suitable landing areas in emergent rescue situations. To our knowledge, this is the first GIScience study focused on estimating the location of landing zones for a search-and-rescue application. 相似文献
957.
Since the U.S. Embassy in Beijing placed an air quality sensor on its roof and began publishing the results on Twitter in 2008, air quality has gained widespread attention on Chinese microblogs. When the Chinese government introduced new air quality standards in 2012, some hailed this as a victory for Chinese microbloggers, signifying the emergence of social media as a democratizing force leading to greater citizen power. Using a representative sample of microblog posts collected from October 2012 to June 2013 on the topic of air pollution, as well as contextual information from a variety of sources, we examine how the government, companies, nongovernmental organizations, and individuals approach the Chinese social media landscape. We find that although microblogs are capable of empowering citizens to advance an environmental cause, social media have also been increasingly employed by the government as a tool for social monitoring and control and by companies as a platform for profiting from air pollution. 相似文献
958.
《The Professional geographer》2013,65(2):191-205
Abstract This article examines political regionalism in presidential elections from 1892 to 2000 by analyzing the percentage of the popular vote received by Democratic candidates for president using statistical methods and spatial analysis. The results indicate three long-term and stable political regions in presidential elections and a history of spatially dependent voting. The article then proposes four fluid political regions based on social diversity and recent political behavior and integrates the role of the Electoral College. This provides a framework in which political geography can integrate political regionalism, racial and social diversity, and the electoral vote in studying presidential elections. 相似文献
959.
《The Professional geographer》2013,65(2):163-176
Describing and explaining land-use change is of critical concern in Madagascar, where land transformations such as deforestation and resulting environmental degradation currently capture widespread attention. While the eastern rain forest recedes in the face of swidden cultivators, the highlands demonstrate more constructive transformations. In this paper I present a case study of land-use change in Leimavo, a small village near Ambositra studied in the 1960s by Jean-Pierre Raison. Here, the twentieth century has seen a gradual reduction in irrigated rice cultivation and cattle husbandry, and a boom in market-oriented orange, vegetable, and grain production. In the long term, a historical landscape of grassy hills has been transformed into a productive cultural landscape with woodlots, anti-erosion benching, rice terraces, fruit groves, and diverse crops. Critical factors determining the trajectory of land-use change include regional population pressure, state policies, market incentives, climate variations, and access to land and water resources. These critical factors, or explanations, are linked in the discussion by the use of a simple heuristic device—the range of choice—as a theoretical framework. 相似文献
960.