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   156篇
  免费   1篇
安全科学   2篇
废物处理   8篇
环保管理   13篇
综合类   37篇
基础理论   26篇
污染及防治   54篇
评价与监测   8篇
社会与环境   9篇
  2022年   8篇
  2021年   2篇
  2020年   2篇
  2018年   7篇
  2017年   8篇
  2016年   10篇
  2015年   5篇
  2014年   11篇
  2013年   12篇
  2012年   16篇
  2011年   14篇
  2010年   12篇
  2009年   4篇
  2008年   8篇
  2007年   13篇
  2006年   6篇
  2005年   6篇
  2004年   2篇
  2003年   1篇
  2002年   3篇
  2001年   1篇
  1998年   1篇
  1994年   2篇
  1991年   1篇
  1989年   1篇
  1981年   1篇
排序方式: 共有157条查询结果,搜索用时 15 毫秒
41.
Radon concentration measurements in atmosphere were taken in years from 1997 to 1999 in Milan and at pre-alpine sites located north of Lombardy. In this paper the results of measuring campaigns and a comparison of radon levels observed in the hilly area north of the town and on the pre-Alps are reported. The general criteria of the measurements and the interpretative models of radon concentration are presented. The Lake Maggiore area shows evidence of a great nocturnal stability and frequent formation of Nocturnal Stable Layer. The peculiar findings in the high altitude stations confirm the use of radon as an indicator of atmospheric dispersion of pollutants in an area with complex orography. The afternoon minimum values are concordant for the different stations: this implies a remixing in afternoon hours over the whole area investigated.  相似文献   
42.
43.
44.
Knowledge on ecosystem functioning can largely contribute to promote ecosystem-based management and its application. The Mar Piccolo of Taranto is a densely populated area at a high risk of environmental crisis. Here, planktonic primary production (PP) and heterotrophic prokaryotic production (HPP) were measured as proxies of functioning in three sampling sites located in two inlets at different levels of industrial contamination, during three sampling surveys (June 2013, February and April 2014). To have a better overall view and provide some insights into the benthic-pelagic coupling, we integrated PP and HPP in the water column with those in the sediments and then discussed this with the origin of the organic matter pools based on analysis of stable isotopes. Heavy metals and polychlorobiphenyls (PCBs) were also analysed in the surface (1 cm) sediment layer and related to the overall ecosystem functioning. Multidimensional scaling (MDS) analysis, based on the main data, clearly separated the second inlet from the first one, more severely impacted by anthropogenic activities. The stable isotope mixing model suggested the prevalent terrestrial/riverine origin of the particulate organic matter pools (mean 45.5 %) in all sampling periods, whereas phytoplankton contributed up to 29 % in February. Planktonic PP and HPP rates followed the same pattern over the entire study period and seemed to respond to phytoplankton dynamics confirming this community as the main driver for the C cycling in the water column. On the contrary, benthic PP rates were almost negligible while HPP rates were lower or comparable to those in the water column indicating that although the Mar Piccolo is very shallow, the water column is much more productive than the surface sediments. The sediment resuspension is likely responsible for a pulsed input of contaminants into the water column. However, their interference with the proper functioning of the pelagic ecosystem seems to be limited to the bottom layers.  相似文献   
45.
A monitoring program was carried out in bathing waters along the sea-coast of the Adriatic Sea. The investigation was aimedat obtaining a quali-quantitative picture of microorganisms ofanthropic origin and of a more strictly autochthonous origin and at verifying the existence of possible reciprocal correlations and combinations of relationship between them. Results showed that the concentrations of indicators of faecal contamination, whether within or over the values established by legislation, are not always related to the presence and density of microorganisms of environmental origin but the regression modelsused can help to describe how these latter microorganisms can bein relation to levels of the other parameters. The difficultyis evident of the predictability of health effects swimming-associated; for this reason more complex models that are currently used should be taken into account for minimising the risk for bathers.  相似文献   
46.
47.
48.
The case described in this article regards 4.7 km of beach in Ferring, situated approx. 5 km south to the mouth of the Limfjord strait on the west coast of Denmark. In 2005, this section of the beach was nourished with 721,000 m3 of material in order to protect backshore properties, natural heritages and the recreational value of the beach. After the nourishment, the beach was monitored by levelling profiles on four dates to monitor and track the evolution of the nourished material. Furthermore, laboratory tests involving different gradations of nourishment material are shown which indicate solutions to different kinds of coastal protection strategies, estimate the time in between two nourishments and evaluate the cost of maintaining a beach with a high recreational value for the public.  相似文献   
49.
The ctenophore Bolinopsis vitrea has been rarely observed in the Mediterranean Sea. A bloom of B. vitrea is here reported for the first time in the southern Adriatic Sea in the spring and summer of 2009, together with its effect on the plankton of Kotor Bay. Ctenophores were found below 5 m depth only. Results of the investigation indicate that mass occurrence of B. vitrea could have a great impact on the Kotor Bay ecosystem. Their predation on copepods would reduce grazing pressure on phytoplankton, favouring an uncommon bloom of the latter. It is evident that B. vitrea are capable of altering rapidly the composition and biomass of coastal plankton communities when present in large masses. This first evidence of such events for this species may indicate changes in the functioning of marine ecosystems of the southern Adriatic.  相似文献   
50.
The National Project RITMARE (la Ricerca ITaliana per il MARE—Italian Research for the sea) started from 1 January 2012. It is one of the national research programs funded by the Italian Ministry of University and Research. RITMARE is coordinated by the National Research Council (CNR) and involves an integrated effort of most of the scientific community working on marine and maritime issues. Within the project, different marine study areas of strategic importance for the Mediterranean have been identified: Among these, the coastal area of Taranto (Ionian Sea, Southern Italy) was chosen for its different industry settlements and the relative impact on the marine environment. In particular, the research has been concentrated on the Mar Piccolo of Taranto, a complex marine ecosystem model important in terms of ecological, social, and economic activities for the presence also of extensive mussel farms. The site has been selected also because the Mar Piccolo area is a characteristic “on field” laboratory suitable to investigate release and diffusion mechanisms of contaminants, evaluate chemical–ecological risks towards the marine ecosystem and human health, and suggest and test potential remediation strategies for contaminated sediments. In this context, within the project RITMARE, a task force of researchers has contributed to elaboration a functioning conceptual model with a multidisciplinary approach useful to identify anthropogenic forcings, its impacts, and solutions of environmental remediation. This paper describes in brief some of the environmental issues related to the Mar Piccolo basin.  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