全文获取类型
收费全文 | 5321篇 |
免费 | 45篇 |
国内免费 | 25篇 |
专业分类
安全科学 | 114篇 |
废物处理 | 255篇 |
环保管理 | 378篇 |
综合类 | 856篇 |
基础理论 | 1309篇 |
环境理论 | 5篇 |
污染及防治 | 1749篇 |
评价与监测 | 416篇 |
社会与环境 | 292篇 |
灾害及防治 | 17篇 |
出版年
2023年 | 59篇 |
2022年 | 136篇 |
2021年 | 150篇 |
2020年 | 73篇 |
2019年 | 82篇 |
2018年 | 188篇 |
2017年 | 206篇 |
2016年 | 267篇 |
2015年 | 186篇 |
2014年 | 278篇 |
2013年 | 419篇 |
2012年 | 311篇 |
2011年 | 345篇 |
2010年 | 229篇 |
2009年 | 195篇 |
2008年 | 332篇 |
2007年 | 293篇 |
2006年 | 243篇 |
2005年 | 190篇 |
2004年 | 172篇 |
2003年 | 151篇 |
2002年 | 128篇 |
2001年 | 82篇 |
2000年 | 41篇 |
1999年 | 47篇 |
1998年 | 25篇 |
1997年 | 21篇 |
1996年 | 22篇 |
1995年 | 32篇 |
1994年 | 30篇 |
1993年 | 10篇 |
1992年 | 21篇 |
1991年 | 21篇 |
1990年 | 21篇 |
1989年 | 16篇 |
1988年 | 15篇 |
1987年 | 11篇 |
1986年 | 25篇 |
1985年 | 13篇 |
1984年 | 12篇 |
1983年 | 13篇 |
1982年 | 19篇 |
1981年 | 10篇 |
1980年 | 13篇 |
1966年 | 17篇 |
1965年 | 12篇 |
1964年 | 10篇 |
1958年 | 10篇 |
1956年 | 11篇 |
1954年 | 9篇 |
排序方式: 共有5391条查询结果,搜索用时 0 毫秒
61.
Gentaz Lucile Saheb Mandana Verney-Carron Aurélie Sessegolo Loryelle Chabas Anne Nuns Nicolas Remusat Laurent Gonzalez-Cano Adriana Fourdrin Chloé Mertz Jean-Didier 《Environmental science and pollution research international》2021,28(3):2810-2821
Environmental Science and Pollution Research - For a long time, limestone has been massively used in stone building and monuments because of its easy extraction and common presence in the... 相似文献
62.
Vicente Estela Domingos Alves Célia A. Martins Vânia Almeida Susana Marta Lazaridis Mihalis 《Environmental science and pollution research international》2021,28(46):65385-65398
Environmental Science and Pollution Research - Residential settings are of utmost importance for human exposure, as it is where people spend most of their time. Residential wood combustion is a... 相似文献
63.
Svensson Teresia Kylin Henrik Montelius Malin Sandén Per Bastviken David 《Environmental science and pollution research international》2021,28(7):7691-7709
Environmental Science and Pollution Research - Chlorine (Cl) in the terrestrial environment is of interest from multiple perspectives, including the use of chloride as a tracer for water flow and... 相似文献
64.
Jaime E. Jiménez Aldo M. Arriagada Francisco E. Fontúrbel Patricio A. Camus M. Isidora Ávila-Thieme 《Die Naturwissenschaften》2013,100(8):779-787
Salmon farming is a widespread activity around the world, also known to promote diverse environmental effects on aquatic ecosystems. However, information regarding the impact of salmon farming on bird assemblages is notably scarce. We hypothesize that salmon farming, by providing food subsidies and physical structures to birds, will change their local community structure. To test this hypothesis, we conducted a seasonal monitoring of bird richness, abundance, and composition at paired salmon pen and control plots in two marine and two lake sites in southern Chile, from fall 2002 to summer 2004. Overall, salmon farming had no significant effects on species richness, but bird abundance was significantly and noticeably higher in salmon pens than in controls. Such aggregation was mainly accounted for by the trophic guilds of omnivores, diving piscivores, carrion eaters, and perching piscivores, but not by invertebrate feeders, herbivores, and surface feeders. Species composition was also significantly and persistently different between salmon pens and controls within each lake or marine locality. The patterns described above remained consistent across environment types and seasons indicating that salmon farming is changing the community structure of birds in both lake and marine habitats by promoting functional and aggregation responses, particularly by favoring species with broader niches. Such local patterns may thus anticipate potential threats from the ongoing expansion of the salmon industry to neighboring areas in Chile, resulting in regional changes of bird communities, toward a less diverse one and dominated by opportunistic, common, and generalist species such as gulls, vultures, and cormorants. 相似文献
65.
Ghostin J Habib-Jiwan JL Rozenberg R Daloze D Pasteels JM Braekman JC 《Die Naturwissenschaften》2007,94(7):601-605
The adults of the leaf beetle Platyphora kollari (Chrysomelidae) are able to metabolise the oleanane triterpene β-amyrin (1) into the glycoside 3-O-β-d-glucopyranosyl-(1→4)-β-d-glucuronopyranosyl-hederagenin (2) that is stored in their defensive glands. The aim of this study was to test the hypothesis that oleanolic acid (3) is an intermediate in the conversion of 1 into 2 and to check whether the sequestration of pentacyclic triterpenes is selective in favour of β-amyrin (1). To this end, adults of P. kollari were fed with Ipomoea batatas leaf disks painted with a solution of [2,2,3-2H3]oleanolic acid or [2,2,3-2H3]α-amyrin and the secretion of their defensive glands analysed by HPLC–ESIMS. The data presented in this work indicated that
the first step of the transformation of β-amyrin (1) into the sequestered glycoside 2 is its oxidation into oleanolic acid (3) and that this conversion is selective but not specific in favour of β-amyrin (1). 相似文献
66.
INTRODUCTION: Nearly all direct observation studies of safety belt use are conducted exclusively during daylight hours. Recent work has suggested that safety belt use at night may differ from daytime belt use. METHODS: An observational study of nighttime safety belt use, utilizing specialized night vision equipment, was conducted in Indiana surrounding the Click It or Ticket 2006 safety belt mobilization activities. A pre- and a post-mobilization statewide direct observation survey was conducted at night coinciding with daytime safety belt use data collection conducted by the state of Indiana. Daytime and nighttime belt use rates were compared. RESULTS: The comparisons across the mobilization period revealed a significant increase during the day, but a significant decrease at night. Comparisons between daytime and nighttime belt use revealed no overall difference during the pre wave, but a significant difference during the post wave. Finally, many common daytime trends in belt use were also found at night, with the exception of the typical age and seating position effects. DISCUSSION: The mobilization activities had a positive effect on daytime belt use, but no effect on nighttime belt use, likely resulting in the differences between daytime and nighttime belt use observed during the post wave. IMPACT ON INDUSTRY: The findings of this study suggest that safety belt mobilizations implemented only during the day do not influence nighttime safety belt use. Changes to how these programs are implemented or additional programs specifically targeting belt use at night should be considered, along with continued monitoring of nighttime belt use. 相似文献
67.
Recruitment precision, i.e. the proportion of recruits that reach an advertised food source, is a crucial adaptation of social
bees to their environment. Studies with honeybees showed that recruitment precision is not a fixed feature, but it may be
enhanced by factors like experience and distance. However, little is known regarding the recruitment precision of stingless
bees. Hence, in this study, we examined the effects of experience and spatial distance on the precision of the food communication
system of the stingless bee Scaptotrigona mexicana. We conducted the experiments by training bees to a three-dimensional artificial patch at several distances from the colony.
We recorded the choices of individual recruited foragers, either being newcomers (foragers without experience with the advertised
food source) or experienced (foragers that had previously visited the feeder). We found that the average precision of newcomers
(95.6 ± 2.61%) was significantly higher than that of experienced bees (80.2 ± 1.12%). While this might seem counter-intuitive
on first sight, this “loss” of precision can be explained by the tendency of experienced recruits to explore nearby areas
to find new rewarding food sources after they had initially learned the exact location of the food source. Increasing the
distance from the colony had no significant effect on the precision of the foraging bees. Thus, our data show that experience,
but not the distance of the food source, affected the patch precision of S. mexicana foragers. 相似文献
68.
Leclaire S Merkling T Raynaud C Giacinti G Bessière JM Hatch SA Danchin E 《Die Naturwissenschaften》2011,98(7):615-624
The importance of olfaction in birds’ social behavior has long been denied. Avian chemical signaling has thus been relatively
unexplored. The black-legged kittiwake provides a particularly appropriate model for investigating this topic. Kittiwakes
preferentially mate with genetically dissimilar individuals, but the cues used to assess genetic characteristics remain unknown.
As in other vertebrates, their body odors may carry individual and sexual signatures thus potentially reliably signaling individual
genetic makeup. Here, we test whether body odors in preen gland secretion and preen down feathers in kittiwakes may provide
a sex and an individual signature. Using gas chromatography and mass spectrometry, we found that male and female odors differ
quantitatively, suggesting that scent may be one of the multiple cues used by birds to discriminate between sexes. We further
detected an individual signature in the volatile and nonvolatile fractions of preen secretion and preen down feathers. These
results suggest that kittiwake body odor may function as a signal associated with mate recognition. It further suggests that
preen odor might broadcast the genetic makeup of individuals, and could be used in mate choice to assess the genetic compatibility
of potential mates. 相似文献
69.
For more than 30 million years, in early Mesozoic Pangea, ??rauisuchian?? archosaurs were the apex predators in most terrestrial ecosystems, but their biology and evolutionary history remain poorly understood. We describe a new ??rauisuchian?? based on ten individuals found in a single locality from the Middle Triassic (Ladinian) Santa Maria Formation of southern Brazil. Nine articulated and associated skeletons were discovered, three of which have nearly complete skulls. Along with sedimentological and taphonomic data, this suggests that those highly successful predators exhibited some kind of intraspecific interaction. Other monotaxic assemblages of Triassic archosaurs are Late Triassic (Norian-Rhaetian) in age, approximately 10 million years younger than the material described here. Indeed, the studied assemblage may represent the earliest evidence of gregariousness among archosaurs, adding to our knowledge on the origin of a behavior pattern typical of extant taxa. 相似文献
70.
Hermann Comoé Robert Finger Dominique Barjolle 《Mitigation and Adaptation Strategies for Global Change》2014,19(2):123-142
This paper investigates threats to farm management in the northern and central region of Côte d’Ivoire, with a particular focus on climate-related threats. To this end, farmers’ perception and adaptation strategies for climate change have been analyzed. The data were collected from 205 respondents by means of the Focus Groups method, and they were evaluated using a framework analysis. The main reported threats related to the implementation of farming activities are the high cost of inputs and the lack of technical support, which are followed by diseases, insects, and climate variations (scarcity of rains, strong winds, and high temperature). We find that most farmers have a strong perception of changes in climatic conditions. Their perceived impacts on the local environment through evidences like the disappearance of certain farming practices, occurrence of new insects, and the disruption of key time reference periods. Farmers mainly attempt to adapt by adjusting their agricultural calendar, adopting new short-season varieties, and using mixed cropping. We find that the most influential factors for farmers’ adaptation behavior is lack of contact with extension services and the scarcity of rainfall. Our suggestions for future agricultural policies for better adaptation to climate change are to take into account farmers’ perception, to provide suitable climate forecast, and to improve local technical support. 相似文献