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991.
基于遥感和GIS的中国土地资源生态环境质量同人口分布的关系研究 总被引:50,自引:2,他引:48
基于用数字环境模型对中国土地资源生态环境质量评价的基础上,生成了中国土地资源生态环境综合评价图和人口密度分布图。首先分析了中国土地资源生态环境等级面积构成及分布状况,中国土地资源生态环境质量最好的地区全部分布在东南沿海和四川盆地地区,之后,用相关分析方法及关系曲线分析了中国土地资源生态环境质量同人口分布的关系,得出了土地资源生态环境质量指数同人口存在着实质性的相关关系,中国东南沿海和四川盆地地区是中国土地资源生态环境最好的地区,也是人口密度和土度资源利用程度最高的地区,而西北及青藏高原区是中国土地资源生态环境比较差的地区,也是人口密度比较低的地区。 相似文献
992.
Michael Jerrett 《The Professional geographer》1999,51(1):115-134
Governments at all levels expend resources to defend the environment from the adverse effects of human activity. Currently little is known about the processes and variables associated with these environmentally “defensive” expenditures. This paper attempts to fill this void by addressing the following research question: What factors induce municipal governments to expend scarce resources to defend against the adverse effectsof environmental change? The paper tackles this question with a combination of traditional statistical analysis and new environmental accounting techniques.Specifically, budgetary content analyses and secondary data are combined to develop a multiple regression model. The model uses the 1991 per capita defensive expenditures of 832 municipal governments as the response variable. These data are aggregated into 49 regions to ensure administrative commensurability. Model selection began with a wide array of predictor variablesthought to exert an influence on the defensive expenditures. The final model includes four predictor variables: provincial transfer payments for defensive expenditures per capita, property taxes per capita, median household income, and total pollution output per region. These four variables are significantly and positively associated with 73.5% of the variation in defensive expenditures (adjusted R2 = .735, p < .0001). Aninterpretation of the results suggests a need for a more place-sensitive approach to environmental accounting to ensure differences in environmental quality do not confound the analysis. 相似文献
993.
室内外培养海洋单细胞微藻的生长及生化组分 总被引:1,自引:0,他引:1
利用现有的螺旋藻培养基地 ,初步尝试了对海洋单细胞微藻(球等鞭金藻Isochrysisgalbana)的大规模室外培养 ,研究了藻细胞在室内外不同培养条件下的生长规律 ,并对其生化成分进行了分析 ,发现实验藻种对培养条件表现出一定的适应性。在室外条件下 ,细胞内脂类、蛋白质的含量都有较大的下降 ,分别从细胞干重的17.045%和4.412%下降为9.746%和2.254 %。与此同时 ,细胞内糖类含量却大大增加 ,高达干重的30.067 % ,比室内培养增加了25.08 % ,且是所有组分中最高的。室外培养细胞内灰分的含量也高于室内。 相似文献
994.
中国环境生态形势的空间分异研究 总被引:4,自引:1,他引:3
在国内外环境生态形势研究的基础上,结合我国的环境生态形势特征,构建了我国环境生态形势的评价指标体系,以县域为单位,进行了自然、社会、经济多因素的综合性研究,定量计算出各县环境生态形势指标值,绘制成图,可见,我国危急环境生态形势主要分布在自然地理环境的过渡带和人类生活动的不稳定带上(包括农牧交错带和不同和地政单元的交界地带),这些地区表现出强裂的界面性和波动性,了解我国环境生态形势的空间分异规律可为区域环境的开发、利用和整治以及制订可持续发展战略提供参考。 相似文献
995.
于2009年8月在海南省东寨港、亚龙湾青梅港和三亚河口红树林区,分别采用自行研制的沉积物耗氧量(Sediment oxygen demand,SOD)测定装置,对红树林湿地SOD和相关环境因子进行研究。结果表明,红树林湿地沉积物耗氧主要分为2个阶段,即瞬时耗氧阶段和渐缓耗氧阶段。3个站位的SOD值范围为102.2-157.7mg/(m2·h),其中瞬时耗氧占23.3%-45.5%。SOD与沉积物中的硫化物含量及上覆水中的化学耗氧量(Chemical oxygen demand,COD)、NH4+浓度有显著的相关性。研究结果表明,红树林湿地沉积物能对其上覆水释放有机物并消耗水体中的溶解氧,使水质变差,因此,用红树林湿地处理城市污水可能导致生态恶化。 相似文献
996.
This article addresses the present status of seafood-oriented environmental methods and analyses, and pinpoints areas for further development. A recent study of the CO2 emissions associated with the production of farmed salmon in Norway, following the life cycle from hatching to consumption, is presented. The study was initiated due to the increased focus on environmental impacts from food production among consumer organizations, retailers, and authorities. In general, several methods are being currently applied to measure environmental performance. Unfortunately, different methods provide quite different results. An additional challenge is that most of these methods were originally developed for land-based production. If assumptions about the performance of the seafood industry are established on the basis of incorrect information, consequences for both the management and the market level may not be desirable. 相似文献
997.
This paper considers the overall outcome of a “public environmental audit” of the government management of the oil and gas offshore industry in eastern Canada. Five requests for data sets were placed using the Access to Information Act; all five requests were denied by the Canada-Newfoundland Labrador Offshore Petroleum Board. This lack of access to environmental monitoring data significantly hinders the ability of independent scientific inquiry and/or public involvement in the environmental assessment process. 相似文献
998.
The social acceptability of aquaculture is linked to its perceived environmental impact, and this clearly poses a challenge to policy makers in deciding what weight to attach to such a concern within a governance framework for the industry. Using salmon farming in Scotland as a case study, we have developed a survey-based approach to evaluating public and stakeholder attitudes towards the environmental performance of aquaculture. The survey of the general public finds marked regional variations in attitudes towards salmon farming, while the results of the stakeholder survey raise issues over how far the preferences of particular interest groups are truly representative of the community as a whole. 相似文献
999.
This article examines the influence of patterns of emergence on the effectiveness of the Marine Stewardship Council (MSC)—a leading wild-capture fisheries certification program. Looking first at the origins and features of this program, direct effects are examined by describing the adoption of the scheme and the impacts of the fishery assessment process. In assessing broader consequences, the article examines patterns of adoption and certification effects that were not necessarily intended or anticipated. The article concludes that fisheries certification alone is unlikely to arrest the decline of fish stocks, and highlights the need for more research on the intersection of private and public efforts to address overfishing and environmental harm resulting from fishing. 相似文献
1000.
营造图书馆绿色环境有利于发挥图书馆教育职能、培养读者的审美情趣与艺术欣赏力并提高读者的道德修养,从建筑和环境等方面加强图书馆绿色环境建设是创建现代化图书馆新思路。 相似文献