全文获取类型
收费全文 | 2556篇 |
免费 | 132篇 |
国内免费 | 1073篇 |
专业分类
安全科学 | 156篇 |
废物处理 | 137篇 |
环保管理 | 207篇 |
综合类 | 1547篇 |
基础理论 | 409篇 |
环境理论 | 1篇 |
污染及防治 | 965篇 |
评价与监测 | 115篇 |
社会与环境 | 105篇 |
灾害及防治 | 119篇 |
出版年
2024年 | 6篇 |
2023年 | 62篇 |
2022年 | 158篇 |
2021年 | 115篇 |
2020年 | 105篇 |
2019年 | 97篇 |
2018年 | 92篇 |
2017年 | 122篇 |
2016年 | 171篇 |
2015年 | 201篇 |
2014年 | 186篇 |
2013年 | 244篇 |
2012年 | 223篇 |
2011年 | 241篇 |
2010年 | 210篇 |
2009年 | 182篇 |
2008年 | 169篇 |
2007年 | 162篇 |
2006年 | 149篇 |
2005年 | 70篇 |
2004年 | 68篇 |
2003年 | 88篇 |
2002年 | 74篇 |
2001年 | 58篇 |
2000年 | 70篇 |
1999年 | 73篇 |
1998年 | 62篇 |
1997年 | 56篇 |
1996年 | 55篇 |
1995年 | 45篇 |
1994年 | 39篇 |
1993年 | 35篇 |
1992年 | 17篇 |
1991年 | 11篇 |
1990年 | 9篇 |
1989年 | 7篇 |
1988年 | 4篇 |
1987年 | 4篇 |
1986年 | 4篇 |
1985年 | 2篇 |
1984年 | 3篇 |
1983年 | 3篇 |
1982年 | 2篇 |
1981年 | 1篇 |
1977年 | 1篇 |
1972年 | 2篇 |
1918年 | 1篇 |
1917年 | 1篇 |
1916年 | 1篇 |
排序方式: 共有3761条查询结果,搜索用时 15 毫秒
751.
752.
Wang Junsong He Canfei 《中国人口.资源与环境(英文版)》2009,7(2):44-49
China has witnessed rapid economic development since 1978, and during the time, energy production and consumption developed at a tremendous speed as well. Energy efficiency which can be measured by energy consumption per unit of GDP, however, experienced continuous decrease. Theoretically, the change of energy efficiency can be attributed to industry structural change and technological change. In order to explain the transformation of Chinese energy efficiency, we adopt logarithmic mean Divisia index techniques to decompose changes in energy intensity in the period of 1994-2005. We find that technological change is the dominant contributor in the decline of energy intensity, but the contribution has declined since 2001. The change in industry structure has decreased the energy intensity before 1998, but raised the intensity after 1998. Decomposed technological effects for all sectors indicate that technological progresses in high energy consuming industries such as raw chemical materials and chemical products, smelting and pressing of ferrous metals, manufacture of non-metallic mineral products and household contribute are the principal drivers of China's declining energy intensity. 相似文献
753.
Based on the analysis on the global economic crisis,climate change crisis and their mutual underlying reasons,the authors believe that low-carbon economy has become an inevitable choice to break through the dual crises,coordinate the economic development,and protect the global climate.The global trend of low-carbon economy finds expression in Green Recovery currently,while,in a long run,it will give rise to a new pattern of world competition in politics,economy,technology,trade and finance.The impact of the... 相似文献
754.
Reconstructed cropland in the mid-eleventh century in the traditional agricultural area of China: implications of comparisons among datasets 总被引:6,自引:0,他引:6
Reconstructions of historical cropland area and spatial distribution are necessary for studying human effects on the environment due to agricultural development. To understand the current status of reconstructions of cropland area and its spatial distribution in the mid-eleventh century in the traditional agricultural area of China, we compared three available datasets: the historic cropland inventories-based HE dataset, the population-based History Database of the Global Environment (HYDE) dataset, and the PJ dataset. The results indicate that the HYDE and PJ datasets estimated the regional mean cropland area fraction (a ratio of cropland area to total land area, hereafter, CAF) for the study area to be 0.12 and 0.09, respectively, both of which were lower than the HE estimation of 0.18. Moreover, both the HYDE and PJ datasets have a poor ability to capture the spatial distribution of the historical CAF. The HYDE dataset overestimated the cropland area in North China and underestimated the cropland area in the Yangtze River reach. The HYDE dataset also overestimated the cropland area along the great rivers in North China. The PJ dataset underestimated the cropland area in the old agricultural area and overestimated the cropland area in the relatively new agricultural area. These incorrect spatial distributions from the HYDE and PJ datasets mainly resulted from the underestimation of the historical population and an incorrect approach for the spatial allocation of cropland within China. The incorrect approach was mainly derived from a poor understanding of the historic spatial distribution of cropland. Using the expert knowledge of local historians may be an effective method to reduce the uncertainties in the global historic cropland reconstruction. 相似文献
755.
Hong Wang Jay Gao Li-Liang Ren Yan Kong He Li Ling Li 《Regional Environmental Change》2013,13(1):115-123
As wildlife habitat is in constant evolution, periodic monitoring is essential to assess its quality. In this study, the change to the red-crowned crane habitat in the Yellow River Delta Nature Reserve was detected from multi-temporal remote sensing data from 1992 to 2008 in a geographic information system. Habitat fragmentation was derived from both physical constraints and human disturbance. The changing habitat quality was assessed against five landscape indices. The results obtained from Landsat TM images indicate that potential habitat shrank 37.9 % during 1992–2001, but recovered 99.4 % by 2008. Suitable habitat shrank by 4,329 ha to a level below that of 1992 despite an increase of 4,747 ha in potential habitat due to an increase of 9,075 ha in fragmented areas. Both landscape indices and the red-crowned crane population reveal that suitable habitat was the most fragmented in 2001, but the least fragmented in 1992. Therefore, it is inadequate to just restore wetland through artificial diversion of channel flow to the Reserve to preserve the crane habitat. Commensurate efforts should also be directed at improving habitat quality by minimizing human activities and spatially juxtaposing water and reed marshes harmoniously inside the Reserve. 相似文献
756.
Abstract The study tries to set up a system to extract strategic environmental assessment (SEA) in exploitation of regional development based on the present situation of environmental assessment in China. First, the article summarizes the emphasis and deficiency of international academic community’s SEA research in the past 10 years. Based on this, the article puts forward the concept and evaluation principles of regional strategic environmental assessment (RSEA). Then the article expounds the necessity of carrying out RSEA. After that, the article discusses in detail the process of RSEA, which includes defining evaluation scope, describing regional background, combing strategic behavior, designing development scenarios, predicting the pressure on environment, assessing environmental impact, screening alternatives and proposing regulation and control schemes. 相似文献
757.
ABSTRACTContinuously reducing the CO2 intensity of GDP is the core strategy for developing countries to realize the dual targets of economic growth and CO2 emissions reduction. The measures are twofold: one is to strengthen energy saving and decrease energy intensity of GDP and the other is to promote energy structural decarbonization and reduce CO2 intensity of energy consumption. In order to control global temperature rise no more than 2°C, the decrease in CO2 intensity of GDP needs surpass 4% before 2030, but it could be merely about 2% based on the current trend. Therefore, all countries ought to speed up the low-carbon transition in energy and economy. As for China, keeping a continuous decline in CO2 intensity of GDP of 4%–5% will ensure the realization of the NDC objectives, and also promotes the early peaking of CO2 emissions before 2030. China will play a positive leading role in realizing a win-win low-carbon development coordinating sustainable development and climate change mitigation. 相似文献
758.
With China's rapid economic growth, ecological construction and environmental protection become increasingly important. The regenerated resources industry is an effective way to solve problems, such as resources depletion, energy shortage, and pollution, and it also has strategic importance for the construction of a resource-conserving and environment-friendly society. The regenerated resources industry has been established in Miluo for long time, which includes a recycling system, a processing and utilization system, and a refuse decontamination system. An industrial cluster is in its early stage of development. In order to solve current problems, such as short industrial chain, low processing rate, and low added value, the industrial cluster should be dynamically upgraded by means of technology innovation, chain nucleus creation, and chain extension. We think the industrial cluster of regenerated resources will become a local brand for Miluo, from which other regions or cities will gain valuable experiences and inspirations. 相似文献
759.
文章建立了液相色谱-串联四级杆质谱仪同时测定土壤中四溴双酚A及3种六溴环十二烷同分异构体的分析方法。土壤样品经快速溶剂仪萃取,全自动凝胶净化系统净化后,使用液相色谱-串联四级杆质谱仪,负离子电喷雾多反应监测模式监测,内标法定量分析。结果表明,土壤中四溴双酚A、α-六溴环十二烷、β-六溴环十二烷和γ-六溴环十二烷的检出限为0.1~1.2 pg/g,加标回收率为81.8%~113%,相对标准偏差小于10%。该方法分析时间短,灵敏度高,操作简单,对电子固废拆解场地中的179个土壤样品进行分析,取得满意结果。 相似文献
760.
区域大气环境中PM2.5/PM10空间分布研究 总被引:4,自引:0,他引:4
提出了一种利用移动监测技术研究区域大气环境中PM2.5/PM10空间分布的方法,并在2004年12月进行了宁波市全市域PM2.5/PM10空间分布的研究。数据显示:相同路径所代表的地区PM2.5和PM10具有很好的相关性,多数路径上PM2.5与PM10数据的相关系数平方在0.95以上,而不同路径上PM2.5与PM10的比值不同。文中给出了宁波市PM2.5/PM10污染的空间分布图,直观地显示出PM2.5/PM10污染的空间分布情况,突出了污染的重点点位和地区。 相似文献