全文获取类型
收费全文 | 4291篇 |
免费 | 70篇 |
国内免费 | 199篇 |
专业分类
安全科学 | 78篇 |
废物处理 | 99篇 |
环保管理 | 554篇 |
综合类 | 1010篇 |
基础理论 | 2012篇 |
污染及防治 | 356篇 |
评价与监测 | 119篇 |
社会与环境 | 222篇 |
灾害及防治 | 110篇 |
出版年
2021年 | 1篇 |
2018年 | 114篇 |
2017年 | 116篇 |
2016年 | 207篇 |
2015年 | 43篇 |
2014年 | 13篇 |
2013年 | 23篇 |
2012年 | 239篇 |
2011年 | 283篇 |
2010年 | 95篇 |
2009年 | 43篇 |
2008年 | 22篇 |
2007年 | 41篇 |
2006年 | 42篇 |
2005年 | 593篇 |
2004年 | 1009篇 |
2003年 | 819篇 |
2002年 | 123篇 |
2001年 | 62篇 |
2000年 | 55篇 |
1999年 | 95篇 |
1998年 | 59篇 |
1997年 | 132篇 |
1996年 | 41篇 |
1995年 | 35篇 |
1994年 | 37篇 |
1993年 | 72篇 |
1992年 | 58篇 |
1991年 | 51篇 |
1990年 | 6篇 |
1989年 | 16篇 |
1986年 | 1篇 |
1985年 | 2篇 |
1984年 | 1篇 |
1983年 | 2篇 |
1982年 | 7篇 |
1974年 | 1篇 |
1916年 | 1篇 |
排序方式: 共有4560条查询结果,搜索用时 500 毫秒
301.
Behavioural responses of Diana monkeys to male long-distance calls: changes in ranging,association patterns and activity 总被引:1,自引:0,他引:1
Susanne?ShultzEmail author Charlotte?Faurie Ronald?No? 《Behavioral ecology and sociobiology》2003,53(4):238-245
Although much is known about the relationship between vigilance, group size and predation risk, behavioural responses to predation risk and their resultant costs are less clear. We investigated the response of Diana monkeys to increased predation risk by looking at behavioural changes associated with male long-distance calls, which are reliably given to certain predators. After male long-distance calls, group spread and nearest-neighbour distance decreased whilst travel and association rates for the group increased. The average height and exposure level of individuals in the group did not change after calls. Individual Diana monkeys changed their behaviour and were more likely to be vigilant or travel and less likely to engage in social or resting behaviours after long-distance calls. In addition, movement rates increased with the number of species the Diana monkeys were associated with. Diana monkey long-distance calls facilitate the joining of groups of other species. Black and white colobus and lesser spot-nosed monkeys were more likely to be in an association following a long-distance call than before. Behavioural responses, such as increased travel or association rates, that reduce foraging efficiency are interpreted as evidence of a non-lethal impact of increased predation risk. 相似文献
302.
303.
Willard D Proll G Reder S Gauglitz G 《Environmental science and pollution research international》2003,10(3):188-191
This article is a review of new and versatile optical-immunoassay instrumentation for water monitoring developed through two European Union projects, RIver ANAlyser (RIANA) and Automated Water Analyser Computer Supported System (AWACSS). Both projects utilise immunoassay techniques to isolate the analytes and Total Internal Reflection Fluorescence (TIRF) to quantify them. Completed in 1999, the RIANA project developed a sensitive and cost-effective analytical system capable of simultaneous detection of multiple-analytes in real-world water samples. The AWACSS project has been in progress since 2001 and is developing rugged-but-sensitive instrumentation that will detect up to 30 analytes simultaneously, will operate unattended, and will have networking capability. 相似文献
304.
I.?M.?GrenEmail author M.?Bussolo M.?Hill D.?Pinelli 《Regional Environmental Change》2003,3(4):146-153
The paper calculates the implications of including monetary measurements of environmental emission changes for the welfare
impacts of ecological tax reforms in Italy and Sweden. Taxes on emissions of SO2, NOx and CO2 are investigated. Country-specific computable equilibrium models are used for estimating net welfare changes of the introduction
of these taxes, the incomes of which are used for reducing distorting labour taxes. The results indicate that the inclusion
of environmental benefits reduces the costs of ecological tax reforms considerably for both countries, and may even turn into
net welfare gains. 相似文献
305.
Summary. Detection of heterospecific predators and prey
via chemical cues is well known, but only a few studies have
examined the potential for such discrimination in cannibalistic
systems. In newts, Notophthalmus viridescens, adults are
opportunistic predators of conspecific larvae. I used a laboratory
bioassay to determine whether larvae and adults distinguish
between chemical stimuli from members of the
different age classes. Larvae distinguished between chemical
stimuli from larvae and adults by decreasing their activity
only following exposure to stimuli from adults. Decreased
activity is consistent with an antipredator response in many
prey species, including larval newts. In contrast, adults
increased their activity and increased time spent in open
areas in response to stimuli from larvae, but not to stimuli
from adults. Increased activity is consistent with a feeding
response; adults also showed increased activity and
increased time in open areas in response to chemical stimuli
from familiar heterospecific prey (brine shrimp). The proximate
cue that allowed the newts to distinguish between the
different age classes is not associated with short-term
dietary differences because all stimulus animals were fed the
same prey. Stimulus strength was controlled by diluting the
stimulus solutions according to the volume of the stimulus
animal. Therefore, there appear to be intrinsic differences in
the chemical signatures of larval and adult newts. 相似文献
306.
307.
308.
依靠科学进步,促进防灾减灾 总被引:2,自引:0,他引:2
以科学技术工作为主线 ,系统地总结了陕西省减灾协会 10年来 ,从事自然灾害综合预测、防灾减灾科学研究、学术交流和科普宣传教育等方面的做法、经验和所取得的初步成效 ,以及如何建设好减灾科技社团的体会 相似文献
309.
310.