首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   350篇
  免费   10篇
  国内免费   3篇
安全科学   29篇
废物处理   17篇
环保管理   41篇
综合类   98篇
基础理论   63篇
环境理论   1篇
污染及防治   75篇
评价与监测   21篇
社会与环境   14篇
灾害及防治   4篇
  2024年   1篇
  2023年   2篇
  2022年   2篇
  2021年   2篇
  2020年   6篇
  2019年   4篇
  2018年   14篇
  2017年   12篇
  2016年   28篇
  2015年   13篇
  2014年   14篇
  2013年   38篇
  2012年   19篇
  2011年   32篇
  2010年   15篇
  2009年   17篇
  2008年   22篇
  2007年   15篇
  2006年   22篇
  2005年   15篇
  2004年   12篇
  2003年   8篇
  2002年   6篇
  2001年   7篇
  2000年   1篇
  1999年   6篇
  1998年   1篇
  1997年   1篇
  1996年   2篇
  1995年   1篇
  1994年   1篇
  1992年   4篇
  1991年   4篇
  1990年   2篇
  1987年   1篇
  1983年   6篇
  1982年   2篇
  1970年   1篇
  1966年   2篇
  1963年   1篇
  1959年   1篇
排序方式: 共有363条查询结果,搜索用时 62 毫秒
101.
This paper challenges “Big Society (BS) Localism”, seeing it as an example of impoverished localist thinking which neglects social justice considerations. We do this through a critical examination of recent turns in the localist discourse in the UK which emphasise self-reliant communities and envisage a diminished role for the state. We establish a heuristic distinction between positive and negative approaches to localism. We argue that the Coalition Government's BS programme fits with a negative localist frame as it starts from an ideological assumption that the state acts as a barrier to community-level associational activity and that it should play a minimal role. “BS localism” (as we call it) has been influential over the making of social policy, but it also has implications for the achievement of environmental goals. We argue that this latest incarnation of localism is largely ineffective in solving problems requiring collective action because it neglects the important role that inequalities play in inhibiting the development of associational society. Drawing upon preliminary research being undertaken at the community scale, we argue that staking environmental policy success on the ability of local civil society to fill the gap left after state retrenchment runs the risk of no activity at all.  相似文献   
102.

Introduction  

Environmental heterogeneous methods were used for analysing data sets of trophic state with 11 parameters measured at 12 different sites at Chaohu Lake for the period 2004 to 2006. The aim of this research was to determine spatial/temporal variations in water quality, to assess trophic state and to identify pollution sources. Protective measures and schemes were proposed to improve water quality in the lake.  相似文献   
103.
104.
105.
106.
Sea cucumbers are dominant invertebrates in several ecosystems such as coral reefs, seagrass meadows and mangroves. As bioturbators, they have an important ecological role in making available calcium carbonate and nutrients to the rest of the community. However, due to their commercial value, they face overexploitation in the natural environment. On top of that, occurring ocean acidification could impact these organisms, considered sensitive as echinoderms are osmoconformers, high-magnesium calcite producers and have a low metabolism. As a first investigation of the impact of ocean acidification on sea cucumbers, we tested the impact of short-term (6 to 12 days) exposure to ocean acidification (seawater pH 7.7 and 7.4) on two sea cucumbers collected in SW Madagascar, Holothuria scabra, a high commercial value species living in the seagrass meadows, and H. parva, inhabiting the mangroves. The former lives in a habitat with moderate fluctuations of seawater chemistry (driven by day–night differences) while the second lives in a highly variable intertidal environment. In both species, pH of the coelomic fluid was significantly negatively affected by reduced seawater pH, with a pronounced extracellular acidosis in individuals maintained at pH 7.7 and 7.4. This acidosis was due to an increased dissolved inorganic carbon content and pCO2 of the coelomic fluid, indicating a limited diffusion of the CO2 towards the external medium. However, respiration and ammonium excretion rates were not affected. No evidence of accumulation of bicarbonate was observed to buffer the coelomic fluid pH. If this acidosis stays uncompensated for when facing long-term exposure, other processes could be affected in both species, eventually leading to impacts on their ecological role.  相似文献   
107.
This study examined the toxicity of irgarol, individually and in binary mixtures with three other pesticides (the fungicide chlorothalonil, and the herbicides atrazine and 2,4-D), to the marine phytoplankton species Dunaliella tertiolecta. Standard 96-h static algal bioassays were used to determine pesticide effects on population growth rate. Irgarol significantly inhibited D. tertiolecta growth rate at concentrations > or = 0.27 micro g/L. Irgarol was significantly more toxic to D. tertiolecta than the other pesticides tested (irgarol 96 h EC50 = 0.7 micro g/L; chlorothalonil 96 h EC50 = 64 micro g/L; atrazine 96 h EC50 = 69 micro g/L; 2,4-D 96 h EC50 = 45,000 micro g/L). Irgarol in mixture with chlorothalonil exhibited synergistic toxicity to D. tertiolecta, with the mixture being approximately 1.5 times more toxic than the individual compounds. Irgarol and atrazine, both triazine herbicides, were additive in mixture. The toxicity threshold of 2,4-D was much greater than typical environmental levels and would not be expected to influence irgarol toxicity. Based on these interactions, overlap of certain pesticide applications in the coastal zone may increase the toxicological risk to resident phytoplankton populations.  相似文献   
108.
Summary. The aggressiveness of the house spider (Tegenaria atrica) has a chemical basis in terms of intra- and interspecific chemical communication. Vibrations are used for longer range detection of intruders on the web territory whereas cuticular lipids mediate shorter range agonistic behaviors. Two cuticular acids were shown to promote aggressive responses from adult spiders, whereas mixtures of cuticular alkanes acted as inhibition signals.  相似文献   
109.
110.
The personal assessments of the current and expected future state of the environment by 3232 community respondents in 18 nations were investigated at the local, national, and global spatial levels. These assessments were compared to a ranking of each country's environmental quality by an expert panel. Temporal pessimism (“things will get worse”) was found in the assessments at all three spatial levels. Spatial optimism bias (“things are better here than there”) was found in the assessments of current environmental conditions in 15 of 18 countries, but not in the assessments of the future. All countries except one exhibited temporal pessimism, but significant differences between them were common. Evaluations of current environmental conditions also differed by country. Citizens' assessments of current conditions, and the degree of comparative optimism, were strongly correlated with the expert panel's assessments of national environmental quality. Aside from the value of understanding global trends in environmental assessments, the results have important implications for environmental policy and risk management strategies.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号