全文获取类型
收费全文 | 22991篇 |
免费 | 323篇 |
国内免费 | 350篇 |
专业分类
安全科学 | 739篇 |
废物处理 | 953篇 |
环保管理 | 3075篇 |
综合类 | 3736篇 |
基础理论 | 5688篇 |
环境理论 | 10篇 |
污染及防治 | 5911篇 |
评价与监测 | 1452篇 |
社会与环境 | 1950篇 |
灾害及防治 | 150篇 |
出版年
2022年 | 212篇 |
2021年 | 234篇 |
2020年 | 215篇 |
2019年 | 190篇 |
2018年 | 381篇 |
2017年 | 375篇 |
2016年 | 536篇 |
2015年 | 413篇 |
2014年 | 633篇 |
2013年 | 1865篇 |
2012年 | 808篇 |
2011年 | 1122篇 |
2010年 | 857篇 |
2009年 | 970篇 |
2008年 | 1084篇 |
2007年 | 1160篇 |
2006年 | 947篇 |
2005年 | 820篇 |
2004年 | 825篇 |
2003年 | 756篇 |
2002年 | 717篇 |
2001年 | 852篇 |
2000年 | 686篇 |
1999年 | 395篇 |
1998年 | 268篇 |
1997年 | 292篇 |
1996年 | 273篇 |
1995年 | 337篇 |
1994年 | 267篇 |
1993年 | 256篇 |
1992年 | 222篇 |
1991年 | 234篇 |
1990年 | 236篇 |
1989年 | 226篇 |
1988年 | 191篇 |
1987年 | 166篇 |
1986年 | 196篇 |
1985年 | 185篇 |
1984年 | 233篇 |
1983年 | 172篇 |
1982年 | 210篇 |
1981年 | 187篇 |
1980年 | 172篇 |
1979年 | 188篇 |
1978年 | 116篇 |
1977年 | 124篇 |
1975年 | 116篇 |
1974年 | 119篇 |
1973年 | 115篇 |
1972年 | 127篇 |
排序方式: 共有10000条查询结果,搜索用时 318 毫秒
801.
I. V. Blinova 《Russian Journal of Ecology》2016,47(3):234-240
The spatial structure of 10 populations of rare orchid species (Dactylorhiza incarnata, D. traunsteineri, Listera ovata) has been studied in rich fens sporadically occurring in Murmansk oblast. Two levels of plant aggregation within populations have been distinguished: (1) clusters of individuals and (2) isolated population subsets consisting of clusters. General spatial demographic features of orchid populations in the fens are small area (77 m2) and low ecological density (0.009 ind./m2). Characteristics of the population subsets (their number, area, composition, and distance to the neighboring subset) are species-specific and reflect the degree of species rarity in plant communities. 相似文献
802.
V. M. Emets 《Russian Journal of Ecology》2016,47(4):371-375
The role of ecotones with different (sharp or smooth) spatial boundaries between forest and meadow in ant biodiversity preservation was studied at the right-of-way of a power line in the Voronezh Reserve. The ecotone with a sharp boundary between forest and meadow (transitional zone 2 m wide) had higher species richness of ants compared to the ecotones (also 2 m wide) with smooth boundary between forest and meadow. 相似文献
803.
N. P. Korablev M. P. Korablev P. N. Korablev I. L. Tumanov 《Russian Journal of Ecology》2016,47(3):289-295
A comparative analysis of epigenetic variation has been performed in nine European populations and population groups of the American mink. It has been shown that differentiation of samples in nonmetric characters is due mainly to endogenous processes that have occurred in introduced populations in the course of colonization of new territory by the invasive species. Environmental factors have played a secondary role, with the influence of the geographic (latitudinal) origin of a given sample being considerable and stronger than that of macroclimatic factors. 相似文献
804.
V. G. Tereshchenko D. S. Khrystenko G. O. Kotovska L. I. Tereshchenko 《Russian Journal of Ecology》2016,47(4):364-370
The probable source of stone moroko, Pseudorasbora parva (Temminck & Schlegel, 1846), populations in lake- and stream-type Dnieper reservoirs was revealed. The dynamics and specific growth rates of these populations over 20 years were analyzed. The dynamic phase portrait method was used to determine the timing of stages in the process of invader naturalization and the periods when its populations were in equilibrium. The potential growth rates of P. parva populations in the Kremenchug and Dneprodzerzhinsk reservoirs were estimated. 相似文献
805.
L. E. Yalkovskaya M. A. Fominykh S. V. Mukhacheva Yu. A. Davydova A. V. Borodin 《Russian Journal of Ecology》2016,47(3):281-288
Fluctuating asymmetry (FA) of the mandible shape has been analyzed in bank voles from the zones affected by pollution from three copper smelters in the Urals. It has been shown that there is the necessity for a detailed analysis of the material, since the level of FA may depend on population parameters. Regardless of the pollution level, FA of the mandible region including the lower part of the mandibular body, ramus and processes is higher than in the diastema region. A gradient effect of toxic exposure on FA has been revealed: an increase in its level under increasing technogenic impact is clearly manifested along local pollution gradients. 相似文献
806.
L. P. Agulova N. S. Moskvitina N. P. Bol’shakova L. B. Kravchenko N. V. Ivanova V. N. Romanenko 《Russian Journal of Ecology》2016,47(5):460-466
The dynamics and correlations of ecophysiological parameters have been studied in two spatially separated multispecies communities of murine rodents and ixodid tick larvae and nymphs that parasitize them. It has been shown that all the processes under consideration have nonstationary, oscillatory dynamics. The long-term dynamics of connectivity of ecophysiological characteristics within communities and their synchronization by weather–climatic factors are, by nature, wavelike processes of transitions between the states with stronger and weaker linkage between parameters, which, along with nonstationarity, can contribute to the maintenance of stability and integrity of communities. 相似文献
807.
Julio L. Rivera Amrine Lallmahomed 《International Journal of Sustainable Engineering》2016,9(2):119-129
The aim of this paper was to explore the implications of planned obsolescence (PO) and the associated product lifetime on the environmental impact of products. To achieve this task, a literature review was performed to assess both the historical context and recent situation of planned obsolescence. A search in scholarly journals was performed to evaluate to what extent product lifetime and PO have been discussed in the recent literature. Based on the findings, selected cases of PO are discussed and trends in the practice of limiting product lifetime are identified. Factors considered to have a significant influence on product lifetime have been identified and discussed. The discussion of case studies made it possible to establish the links between product design, manufacturing and associated impacts of lifetime. The role of the actors along the value chain is also considered to propose a business scheme, where the influences of consumer behaviour and design choices are crucial. Finally, strategies to facilitate the definition of different scenarios are given. These strategies may serve to increase the reliability of environmental assessment throughout a product life cycle. 相似文献
808.
809.
The dynamics and structure of the phytomass and production of an undisturbed mesotrophic dwarf shrub–sphagnum phytocenosis and one burned by fire have been compared. The net primary production (NPP) of both sites of phytocenoses in the postpyrogenic period is estimated by direct field determination of the productivity parameters, and C emission from the fire is assessed. The obtained data on emission (0.7 kg/m2) differ from the results obtained in the peatlands of western Canada (3.2 kg/m2). 相似文献
810.
Patterns of expansion of geographical ranges of red deer and Siberian roe deer in Yakutia during the 20th century are considered. The area inhabited by red deer in Yakutia has increased almost fourfold over the past 50 years, with an expansion of over 200000 km2 toward the northwest. The geographical range of roe deer in the Lena–Amga interfluve has also changed considerably during the same period. Roe deer sightings in the subarctic zone were reported. The structure of geographical ranges of the species under investigation in different ecological and geographical regions of Yakutia is discussed, and the factors influencing the transformation of geographical range borders are characterized. 相似文献