全文获取类型
收费全文 | 30211篇 |
免费 | 338篇 |
国内免费 | 250篇 |
专业分类
安全科学 | 1014篇 |
废物处理 | 1464篇 |
环保管理 | 3996篇 |
综合类 | 4744篇 |
基础理论 | 7782篇 |
环境理论 | 8篇 |
污染及防治 | 7422篇 |
评价与监测 | 2138篇 |
社会与环境 | 2051篇 |
灾害及防治 | 180篇 |
出版年
2023年 | 144篇 |
2022年 | 261篇 |
2021年 | 322篇 |
2020年 | 195篇 |
2019年 | 243篇 |
2018年 | 441篇 |
2017年 | 466篇 |
2016年 | 723篇 |
2015年 | 541篇 |
2014年 | 863篇 |
2013年 | 2480篇 |
2012年 | 1021篇 |
2011年 | 1360篇 |
2010年 | 1116篇 |
2009年 | 1155篇 |
2008年 | 1423篇 |
2007年 | 1349篇 |
2006年 | 1221篇 |
2005年 | 1095篇 |
2004年 | 1045篇 |
2003年 | 1003篇 |
2002年 | 943篇 |
2001年 | 1096篇 |
2000年 | 773篇 |
1999年 | 491篇 |
1998年 | 365篇 |
1997年 | 384篇 |
1996年 | 400篇 |
1995年 | 472篇 |
1994年 | 396篇 |
1993年 | 344篇 |
1992年 | 377篇 |
1991年 | 357篇 |
1990年 | 330篇 |
1989年 | 322篇 |
1988年 | 297篇 |
1987年 | 241篇 |
1986年 | 248篇 |
1985年 | 251篇 |
1984年 | 272篇 |
1983年 | 256篇 |
1982年 | 272篇 |
1981年 | 222篇 |
1980年 | 166篇 |
1979年 | 183篇 |
1978年 | 164篇 |
1977年 | 133篇 |
1975年 | 139篇 |
1973年 | 167篇 |
1972年 | 142篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
921.
V. A. Mukhin P. Yu. Voronin T. A. Velivetskaya A. V. Ignat’ev 《Russian Journal of Ecology》2014,45(1):11-17
Data on the ratio of stable carbon isotopes in xylotrophic fungi and their xylic substrates are presented for the first time. It is shown that coniferous substrates are more enriched in the heavy carbon isotope, compared to deciduous substrates. In both cases, however, their carbon isotope composition is characterized by low variability and does not correlate with the species or physiological type of decomposer fungus but shows a statistically significant correlation with the degree of wood mineralization. The ratio of stable carbon isotopes in the fungi depends on that in their substrates but is shifted in favor of the heavier isotope. This trophic shift lacks species specificity, is equally manifested in decomposers of deciduous and coniferous substrates, remains unchanged along the latitudinal climatic gradient, and is positively correlated with the carbon isotope composition of substrates, in the absence of correlation with the degree of their mineralization. 相似文献
922.
Yu. I. Novitskii G. V. Novitskaya D. R. Molokanov Yu. A. Serdyukov 《Russian Journal of Ecology》2014,45(3):201-208
Experiments have been performed to evaluate the impact of weak permanent horizontal magnetic field of about 400 A/m on seed formation in the main magnetic orientation types of radish, the north-south (NS) and west-east (WE) types. The results show that external magnetic field exposure retards plant progression through all stages of ontogeny but does not alter the ratio of NS and WE types. Under its effect, the numbers of pods and seeds and seed weight decrease in the NS-type but increase in the WS-type plants. Therefore, external magnetic field acts as an ecological factor that differentiates the responses of radish plants depending on the type of their magnetic orientation. Differences in the sensitivity of plants to magnetic field exposure are explained by specific features of their physiological status. 相似文献
923.
Probabilistic impacts of climate change on flood frequency using response surfaces II: Scotland 总被引:1,自引:0,他引:1
A. L. Kay S. M. Crooks H. N. Davies N. S. Reynard 《Regional Environmental Change》2014,14(3):1243-1255
This paper uses a sensitivity framework approach to look at the probabilistic impacts of climate change on 20-year return period flood peaks, by applying a set of typical response surfaces alongside the probabilistic UK Climate Projections (UKCP09) for 10 river-basin regions over Scotland. The first paper of the pair used the same approach for 10 river-basin regions over England and Wales. This paper develops the methodology for Scotland, by first enabling better estimation of the response type of Scottish catchments. Then, as for England and Wales, the potential range of impacts is shown for different types of catchment in each river-basin region in Scotland, and regional average impact ranges are estimated. Results show clear differences in impacts between catchments of different types and between regions. The Argyll and West Highland regions show the highest impacts, while the North-East Scotland region shows the lowest impacts. The overall ranges are generally smaller for Scotland than England and Wales. 相似文献
924.
925.
Studies in the vicinities of copper smelters and in undisturbed areas of the Middle Urals have been performed to evaluate the effect of industrial pollution with heavy metals on macro- and micromorphological parameters of kidneys (weight, weight index, the spectrum and frequency of histopathologies) in the bank vole (Clethrionomys glareolus Schreber, 1780) and on the accumulation of Cu, Zn, Cd, and Pb in this organ. It has been found that the kidneys of voles from polluted areas accumulate considerable amounts of heavy metals, with their concentrations increasing with age and/or sexual maturation. The kidney weight, index, and the frequency and severity of the majority of observed nephropathies also increase upon change in the reproductive-age status of animals. These parameters show no dependence on the degree of industrial pollution: at individual level, none of the heavy metals accumulated in the kidneys has produced any effect on the frequency and severity of nephropathies. These results contradict the prevailing opinion that toxicants play the determinant role in the development of nephropathies in small mammals inhabiting polluted areas. Therefore, the causes of nephropathies should be sought among other factors, not related to pollution. 相似文献
926.
927.
The relationship between the principle of free trade and nature conservation is one of the most acute and multifaceted problems in international business. The diversity of WTO activities implies the necessity of interdisciplinary studies utilizing the expertise and experience of specialists in international law and ecologists. In this paper, provisions of the WTO set of agreements and procedures for dispute settlement within the WTO framework are considered as applied to environmental protection. 相似文献
928.
929.
M. A. Potapov I. V. Zadubrovskaya P. A. Zadubrovskii O. F. Potapova V. I. Evsikov 《Russian Journal of Ecology》2012,43(1):40-44
A comparative analysis of reproductive behavior has been performed in the steppe lemming (Lagurus lagurus) and narrow-skulled vole (Microtus gregalis). The results show that the species are similar in certain behavioral features indicative of the stability of mating pairs.
However, in the narrow-skulled vole, unlike in the steppe lemming, mature males in olfactory tests show preference for receptive
sibling females versus non-kin females. Probably, it is the absence of the incest taboo that allows the involvement of young
of the year in reproduction within growing family groups and accounts for “coloniality” of the species. 相似文献
930.
Walter W. Heck John A. Dunning 《Journal of the Air & Waste Management Association (1995)》2013,63(2):112-114
The sensitivity of tobacco and/or pinto bean to ozone, as an air pollutant, is increased by growing plants in a shortened photoperiod under reduced light intensity and in a light potting mix. Sensitivity also is influenced by carbon dioxide concentration, time of day, and age of plant at time of exposure. Plants are more severely injured by a given dose under continuous exposure than when the exposure is split into two time periods. Tobacco shows cumulative development of injury when exposed to low concentrations intermittently over several days. 相似文献