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801.
Research on the internal factors and mechanism of livelihood vulnerability, which has become one of the hot spots in sustainable scientific field, can improve the level of livelihood security. This paper reviewed the livelihood vulnerability literature from the perspective of concept, analysis framework, assessment methods. Three conclusions were achieved. Firstly, the scholars' understanding of the concept of livelihood vulnerability has reached consensus. Secondly, the existing evaluation method is lack of multiple perspectives, and the selection of the indicator system is not comprehensive enough. Thirdly, the research on the dynamic mechanism and regulation of livelihood vulnerability and the framework of adaptability will still be further needed. Additionally, some suggestions were given in this paper such as establishing a unified concept system and analysis framework for livelihood vulnerability, improving the evaluation index system and deepening the dynamic mechanism and regulation study of livelihood vulnerability in the study of livelihood vulnerability. In the future, we should gradually unify the livelihood vulnerability analysis framework, enhance the study of driving and regulating mechanisms and evaluation methods of the livelihood vulnerability, promote the research of livelihood vulnerability in the context of national policies and new technologies, and provide a scientific basis for the formulation of related policies. 相似文献
802.
滑坡位于斜坡中部,面积大、临空面宽,玄武岩碎石土分布广,近期活动明显。经69个钻孔及地表调绘实测,完成稳定性评价及推力计算,有效提供治理依据。 相似文献
803.
生态系统变化:工商业面临的机遇和挑战 总被引:1,自引:0,他引:1
简要介绍了千年生态系统评估(MA)项目编写的《生态系统与人类福祉:工商业面临的机遇和挑战》的核心内容。报告表明:① 工商业与生态系统之间存在着复杂的相互作用,一方面,工商业需要依赖生态系统服务的可持续供给才能得以长期运营,另一方面,工商业的各种活动也会导致生态系统及其服务发生变化;② 在1950—2000年的50年里,全球生态系统已经发生了许多不利于工商业长期持续发展的巨大变化,而且在未来50年内仍会发生一些与工商业密切相关的重要变化;③ 生态系统及其服务的巨大变化已经引起了管理部门的高度重视,今后工商业的发展必然会受到生态系统管理方面的重要影响;④ 工商业的发展要想长期立于不败之地,必须正确、全面地认识生态系统及其服务发生的重大变化,以及它们对业界带来的机遇和挑战,同时对自身的发展战略相应地做出调整。
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804.
《Geoforum》2016
Environmental conservation is increasingly operated through partnerships among state, private, and civil society actors, yet little is known empirically about how such collectives function and with what livelihood and governance outcomes. The landscape approach to conservation (known also as the ecosystem approach) is one such hybrid governance platform. Implemented worldwide over the past decade by international NGOs, the landscape approach employs the ‘ecosystem principles’ of the Convention on Biological Diversity (CBD). In spite of its prominence as a conservation and development strategy, little political ecology scholarship has considered the landscape approach. This article offers a case study of a conservation landscape in the Congo Basin, the Tri-National de la Sangha (TNS), which connects tropical forests in Cameroon, Republic of Congo, and Central African Republic. Led by NGOs, the TNS has since 2001 relied on partnerships among logging companies, safari hunters, the state, and local communities. Although the landscape approach purports to facilitate re-negotiations of user rights, resource access patterns in the TNS appear to have molded to pre-existing power relations. Rather than incorporating local concerns and capabilities into management, local knowledge is discredited and livelihoods are marginalized. As a result, management occurs through spatially-demarcated zones, contrasting the fluidity of interactions among diverse groups: both human (loggers, hunter-gatherers, safari guides, NGOs) and non-human (trees, elephants). These findings are situated within a burgeoning literature on neoliberal environmental governance, and suggest that ensuring ecologically and socially positive outcomes will require careful and iterative attention to linkages between ecological processes and evolving power dynamics. 相似文献
805.
806.
ABSTRACTThis paper provides a study of the changes in land use in urban environments in two cities, Wuhan, China and western Sydney in Australia. Since mixed pixels are a characteristic of medium resolution images such as Landsat, when used for the classification of urban areas, due to changes in urban ground cover within a pixel, Multiple Endmember Spectral Mixture Analysis (MESMA) together with Super-Resolution Mapping (SRM) are employed to derive class fractions to generate classification maps at a higher spatial resolution using an Artificial Neural Network (ANN) predicted Wavelet method. Landsat images over the two cities for a 30-year period, are classified in terms of vegetation, buildings, soil and water. The classifications are then processed using Indifrag software to assess the levels of fragmentation caused by changes in the areas of buildings, vegetation, water and soil over the 30 years. The extents of fragmentation of vegetation, buildings, water and soil for the two cities are compared, while the percentages of vegetation are compared with recommended percentages of green space for urban areas for the benefit of health and well-being of inhabitants. Changes in Ecosystem Service Values (ESVs) resulting from the urbanization have been assessed for Wuhan and Sydney. The UN Sustainable Development Goals (SDG) for urban areas are being assessed by researchers to better understand how to achieve the sustainability of cities. 相似文献
807.
矿井突水危险性评价模型 总被引:9,自引:0,他引:9
用数量化理论 (Ⅱ) 〔1〕研究了矿井突水危险性评价问题, 建立了一个实用的矿井突水危险性评价模型, 为煤矿安全评价开辟了一条新途径。 相似文献
808.
《Singapore journal of tropical geography》2018,39(2):244-265
Mangroves are now well known to provide a range of ecosystem services that benefit local populations, though such ecosystem services are at risk from mangrove deforestation and degradation across much of the tropics. This study aimed to identify the natural and anthropogenic drivers of change that affect ecosystem services of the Sundarbans mangrove forest. Secondary data analysis and primary fieldwork were conducted in three districts in the Sundarbans region of Bangladesh to understand ecosystem service usage and the perceptions of local resource users. Time series data for a range of ecosystem services and biophysical, socio‐economic variables were analyzed to identify the range of trends and the significant drivers of change. Also, community perceptions were consulted to elicit how these changes are felt and how they affected the local ecosystem services users. Results show that most of the ecosystem services of the Sundarbans experienced negative changes over the last two decades. Time series analysis and community perceptions held a number of drivers responsible for these changes. Climatic change, rapid environmental change, demand for mangrove products on the global market, major infrastructure development and governance failure were identified as primary drivers leading to the degradation of ecosystem services of the Sundarbans. The study calls for a transformation in the stewardship of ecosystem services of the Sundarbans and other mangroves across the tropics, to escape the situation where negative environmental impacts might be difficult to reverse. 相似文献
809.
应用生态动力学模型简化法,建立了现场船基培养实验计算营养盐半饱和常数和浮游植物细胞内营养盐比例的方法,并获得了东海甲藻和硅藻的营养盐吸收半饱和常数、营养盐氮磷比和硅氮比的取值范围及建议取值。甲藻:氮半饱和常数2.50μmol/L、磷半饱和常数0.16μmol/L、营养盐氮磷比建议取值为15.80;硅藻:氮半饱和常数3.99μmol/L、磷半饱和常数0.38μmol/L、硅半饱和常数3.35μmol/L、营养盐氮磷比20.45、营养盐硅氮比建议取值为0.49。 相似文献
810.
Being able to analyse the relationships between people and nature has always been of key interest to ecosystems conservation, planning decisions and in a number of disciplines of natural and social sciences. In this framework, it is of paramount importance to evaluate possible correlations between factors such as ecosystem services, human health, and social deprivation. The present study aims at exploring relationships between ecosystem services, human health, and social deprivation for the region of Wales in the United Kingdom. Wales is of special interest because as a region it offers many ‘green’ ecosystems which have already been found to have a positive influence on humans' well-being as well as on socio-economic status. First, a recreational layer showing the size and location of all potential recreational areas in each Welsh local authority was created. Subsequently, correlation/regression analysis and weighted raster analysis were performed which allowed determining quantitatively the degree of correlation between the observed socio-economic factors and recreational areas.The findings of this exploratory study suggested that the relative size of potential recreational area varies widely within the local authorities comprising Wales. Not all the socio-economic factors which were examined herein found to be correlated with recreational areas. Some variables, such as income and employment deprivation showed high correlations with poor recreation options. Very poor correlation was also reported between recreation options and variables such as life expectancy and long-term illness. Our results, in agreement to previous studies conducted elsewhere, suggested that human health is determined by a complex interplay of more than one of the observed determinants, including for example biology and genetics or living and working conditions. As to our knowledge there are no prior research studies on the topic for our study region, this work provides a key contribution concerning the determination of a “social” value of ecosystems in the context of human health and other socio-economic factors. However, as these are only initial results, further work is required to verify those. 相似文献