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411.
农业信息资源可持续开发利用的国际比较及启示 总被引:1,自引:0,他引:1
随着全球经济一体化趋势的增强和知识经济时代的来临,农业信息资源对于农业和农村经济的可持续发展起着至关重要的作用,这在发达国家已经得到实践印证.本文分析了发达国家农业信息资源开发的现状、特征和发展趋势,结合美国、欧盟、德国、法国、澳大利亚、日本、韩国、印度等国家和地区的实际情况,比较分析了国外农业信息资源开发的共性经验和个性差异.在此基础上,针对中国农业信息资源开发利用的现状,提出了国外农业信息资源开发利用对中国的重要启示:突出国家在农业信息资源开发的主体地位,鼓励社会力量积极参与农业信息资源的开发,加强农业基础设施的信息化建设和应用水平,注重农业信息资源科研、教育和推广的结合.为了提高中国农业信息资源开发利用的水平,本文给出了以下政策建议:加强农业信息资源开发利用的重视程度,强化农业信息资源开发队伍的建设力度,提高现有农业信息资源的共事程度,增强农业信意资源的社会服务水平. 相似文献
412.
In recent years, China’s energy demand and Greenhouse gas (GHG) emissions have grown very fast, quite an amount of which was exported as energy embodied in goods in international trade rather than consumed domestically. Starting from the concept of embodied energy, based on input-output energy analysis approach, in this paper the energy embodied in goods in international trade of China during the period from 2001 to 2006 is calculated. The results show that although China has become a net importer of petroleum since 1993, China is a net exporter of embodied energy due to international trade in goods. In 2002, the total amount of energy embodied in exported goods was about 410 million tce (ton of coal equivalent, hereinafter referred to as "tce"). Eliminating the amount of energy embodied in imported goods of about 170 million tce, the net export of embodied energy was about 240 million tce, accounting for 16% of the aggregate primary energy consumption of that very year in China, and the net export of embodied emissions was about 150 million tons of carbon. With the rapid growth of China’s international trade, assuming no structural input-output changes of among sectors, in 2006 the net export of embodied energy went up to about 630 million tce, an increase of 162 % over 2002. In addition, this paper also analyzes the possible sources of error in calculation, and also discusses the policy implications according to the result of the calculation. 相似文献
413.
清江流域水布垭水库二氧化碳大气廓线空间分布及其水环境效应 总被引:2,自引:0,他引:2
为了研究水库水体二氧化碳源汇变化时空分布格局及其影响因素,选择清江流域水布垭水库为典型示范案例,在2010年5月8日到9日开展了二氧化碳观测实验,获取了水库上空大气二氧化碳浓度垂直变化以及沿水库中心线二氧化碳浓度的变化特征。然后基于地理信息系统空间分析技术对观测点二氧化碳浓度数据进行空间插值计算,得到整个水库水体的空间分布特征,并与水环境因子空间分布情况进行比较分析。研究结果表明:水布垭水库上空大气二氧化碳浓度在05 m高度以下最高,然后向上依次降低,其空间分布从水库上游到坝前呈现增加的趋势。同时水库水体二氧化碳浓度变化受到表层水温、叶绿素浓度等水环境重要因素的影响,与水温和气温呈负相关关系,而与叶绿素呈正相关关系 相似文献
414.
环境保护与国际贸易 总被引:2,自引:0,他引:2
张爱国 《城市环境与城市生态》1998,11(1):4-6
从国际环境标准,绿色产品环境标志,国际环保公约等方面研究了近几年环境保护对国际贸易的影响,并根据目前国际环保发展趋势,提出了保护环境和促进我国对外贸易的对策。 相似文献
415.
中国可持续发展战略实施的进展及其趋势 总被引:4,自引:0,他引:4
本文对中国实施可持续发展战略的现状和进展进行了全国的回顾和总结,对未来中国可持续发展的整体态势和主要趋势进行了分析和展望。 相似文献
416.
417.
Judith Kimerling 《Journal of Agricultural and Environmental Ethics》2001,14(4):425-455
The growing assumption thattransnational corporations (TNCs) will apply``best practice' and ``international standards'in their operations in developing countries hasseldom been checked against close observationof corporate behavior. In this article, Ipresent a case study, based on field research,of one voluntary initiative to useinternational standards and best practice forenvironmental protection in the AmazonRainforest, by a US-based oil company,Occidental Petroleum (Oxy) in Ecuador. The moststriking finding is that the company refuses todisclose the precise standards that apply toits operations. This, and the refusal todisclose other important environmentalinformation, make it impossible to verifyindependently Oxy's claims of environmentalexcellence, or assess the effectiveness of theinitiative. At the same time, Oxy uses theinvocation of international standards to wrapitself in a veneer of corporate responsibility;reassure government officials and localresidents; cultivate confusion about standardsand practices that apply to the operations;deflect meaningful oversight and transparency;and arbitrarily legitimize norms that have beendefined by special interests. In short,international standards offer great promise forneeded environmental improvements; but can alsobe used to impede, rather than advance,corporate responsibility and the development ofeffective environmental law at the nationallevel. These findings suggest that for theapplication of international standards to bemeaningful, the international community needsto move beyond statements of principle anddevelop mechanisms that can be used toevaluate, verify, and monitor independentlyenvironmental claims by TNCs. 相似文献
418.
Wenrui Huang William K Jones 《Journal of the American Water Resources Association》2001,37(3):605-615
ABSTRACT: Long‐term freshwater transport is an important factor affecting estuarine aquatic ecosystems. In this study, a primitive equation, prognostic, three‐dimensional, hydrodynamic model was applied to Apalachicola Bay, Florida, for the summer and fall seasons of 1993. In response to the river freshwater discharge, tide, and wind forces, the model simulations were used to characterize the long‐term freshwater transport processes in the bay. Analysis of spatial distributions of seasonal average salinity and currents shows that the long‐term freshwater transport was strongly affected by the forcing functions of wind and density gradient in the bay. Average freshwater input was approximately the same in the summer and fall seasons of 1993. However, in the summer season, more freshwater moved to the east direction due to the predominant wind from the west, while in the fall season more freshwater moved to the west in response to the wind primarily from the east. The water column was strongly stratified near the river mouth, and it gradually changed to well mixing near the ocean boundaries. Vertical stratification in the bay changed due to wind‐induced mixing and mass transport. Due to the density gradient effect, surface residual currents carrying fresher water were in the direction from the river toward the Gulf, while the bottom residual currents with saltier water entered the bay from the Gulf of Mexico. 相似文献
419.
420.
双酚A(BPA)已被证实是一种类雌激素类物质。本研究根据BPA对水生生物毒性效应的特点,按照不同的毒性终点将BPA的毒性数据进行归类,采用物种敏感度分布法(species sensitivity distribution,SSD)推导了BPA对水生生物的预测无效应浓度(predicted no effect concentration,PNEC)。结果表明:以雌激素效应为暴露终点的急、慢性PNEC分别为25.11μg·L-1、1.075μg·L-1;而以所有数据的急、慢性毒性效应为暴露终点推导的PNEC值分别为355.7μg·L-1、7.549μg·L-1。BPA对水生生物的雌激素效应更为敏感,建议在推导BPA这类内分泌干扰物的PNEC值时,应依据其毒性终点分别推导,从而得到更加合理的基准值。研究成果以期为我国地表水环境质量标准的制修订提供数据支持。 相似文献