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   365篇
  免费   4篇
  国内免费   4篇
安全科学   19篇
废物处理   9篇
环保管理   57篇
综合类   87篇
基础理论   54篇
污染及防治   110篇
评价与监测   21篇
社会与环境   11篇
灾害及防治   5篇
  2023年   4篇
  2022年   5篇
  2021年   19篇
  2020年   4篇
  2019年   6篇
  2018年   9篇
  2017年   13篇
  2016年   10篇
  2015年   15篇
  2014年   17篇
  2013年   25篇
  2012年   17篇
  2011年   29篇
  2010年   17篇
  2009年   19篇
  2008年   23篇
  2007年   18篇
  2006年   22篇
  2005年   17篇
  2004年   11篇
  2003年   13篇
  2002年   10篇
  2001年   4篇
  2000年   5篇
  1999年   3篇
  1998年   4篇
  1997年   3篇
  1996年   2篇
  1995年   4篇
  1994年   1篇
  1993年   3篇
  1992年   2篇
  1991年   3篇
  1988年   1篇
  1987年   1篇
  1986年   2篇
  1984年   1篇
  1982年   1篇
  1981年   2篇
  1979年   1篇
  1978年   1篇
  1974年   1篇
  1971年   1篇
  1970年   1篇
  1966年   1篇
  1965年   1篇
  1964年   1篇
排序方式: 共有373条查询结果,搜索用时 15 毫秒
51.
52.
53.
To evaluate exposure to benzene in urban and rural areas, an investigation into personal exposure to benzene in traffic policemen, police drivers and rural (roadmen) male outdoor workers was carried out. Personal samples and data acquired using fixed monitoring stations located in different areas of the city were used to measure personal exposure to benzene in 62 non-smoker traffic policemen, 22 police drivers and 57 roadmen. Blood benzene, urinary trans-trans muconic acid (t,t-MA) and S-phenyl-mercapturic acid (S-PMA) were measured at the end of work shift in 62 non-smoker traffic policemen, 22 police drivers and 57 roadmen and 34 smoker traffic policemen, 21 police drivers and 53 roadmen. Exposure to benzene was similar among non-smoker traffic policemen and police drivers and higher among non-smoker urban workers compared to rural workers. Blood benzene, t,t-MA and S-PMA were similar among non-smoker traffic policemen and police drivers; blood benzene and t,t-MA were significantly higher in non-smoker urban workers compared to rural workers. Significant increases in t,t-MA were found in smokers vs. non-smokers. In non-smoker urban workers airborne benzene and blood benzene, and t,t-MA and S-PMA were significantly correlated. This study gives an evaluation of the exposure to benzene in an urban area, comparing people working in the street or in cars, to people working in a rural area. Benzene is a certain carcinogen for humans. The results we showed should lead to more in-depth studies about the effects on health of these categories of workers.  相似文献   
54.
The Turks and Caicos Islands are currently in the midst of an economic revolution from a marine-based provisional economy to a tourism economy. East Bay, South Caicos, is currently under construction with plans for a 160-unit condominium complex. Included in the project plan is removal of seagrass beds in front of the development to make a sandy beach for tourists. The aims of this study were to (i) describe the bathymetry and benthic habitat coverage of East Bay before dredging takes place and (ii) perform an economic valuation on the turtle grass beds that will be dredged using ecosystem valuation and emergy analysis techniques. The bathymetry survey revealed shallow waters (<1.5 m) until the reef drop off (~650 m offshore). Benthic habitat exhibits zonation following the general progression: sand plain, algal plain, seagrass, coral rubble and seagrass, rock and turf algae, and reef flat. Ecosystem services valued the proposed dredging area at USD $28,807 per year, compared to emergy analysis, which valued the proposed dredging site at USD $32,060 per year. The baselines presented in the study may facilitate a quantitative assessment of dredging impacts on turtle grass once dredging is complete and an economical cost-benefit-analysis of the dredging project to see whether the economic gains outweigh the ecological costs of dredging in front of the East Bay development.  相似文献   
55.
Oritani Marsh in the Hackensack Meadowlands of urbanized northeastern New Jersey USA was assessed in 2000 for vegetation, soil/sediment chemistry, abundance/diversity of benthic invertebrates, and bird and mammal usage. Vegetatively, both marsh and uplands are dominated by tall, dense Phragmites australis. Small patches (less than 2 hectares total) dominated by Spartina spp. were found at the lowest elevations. Soil/sediment cores were sliced into 5 intervals and analyzed for metals, pesticides and volatile/semivolatile organic compounds. Thirteen locations had at least one chemical above Long et al.’s [Environmental Management, 19, 1995, 81--97] “Effects Range-Median” (ERM). Seven metals and nine organics exceeded ERM in at least one sample, with mercury showing the most exceedances. The surface 15 cm interval was generally more contaminated with metals than the 15 to 30 cm interval; the reverse was true for semivolatile organic compounds. Twenty taxa of benthic macroinvertebrates were collected, with each location producing from 1 to 9 taxa. Abundance ranged from 11 to 3,889 individuals/m2. Number of taxa was moderately (r 2 between 0.40 and 0.70) negatively correlated with zinc, beryllium, nickel and arsenic concentrations; no other chemical’s r 2 was above 0.25. Diversity was moderately negatively correlated with arsenic and beryllium. These correlations were unexpected: zinc, beryllium, nickel and arsenic were not the chemicals found at the highest concentrations relative to benchmarks. Number of taxa, abundance and diversity were moderately (negatively) correlated with elevation; organic carbon was moderately (positively) correlated with abundance. All other correlations were weak (r 2 < 0.35). Live traps captured only one mammal species, the meadow jumping mouse. Bird observations revealed 39 species, dominated by a few common species.  相似文献   
56.
57.
In the Recôncavo of Bahia (located between 12°33′ and 13°10′S and 38°00′and 39°00′W), there are significant discharges of SO2 and NOx due to local, industrial and urban activities. The incoming air masses from the Atlantic Ocean are enriched with seaspray, which neutralizes part of the rain acidity. The extent of seaspray neutralization of rain acidity was quantified in four sites of the region, each with different loads of seaspray. Rain samples were obtained daily at the same time, integrating the precipitation of the previous 24 h, using wet-only collectors and analyzed for pH by potentiometry and for sodium by flame photometry. The amount of rain acidity in Recôncavo neutralized by seaspray ranged from <1% up to 88% and depended on the site. On average, neutralization ranged from 5% to 18%.  相似文献   
58.
Climate change represents one of the most pressing societal and scientific challenges of our time. While much of the current research on climate change focuses on future prediction, some of the strongest signals of warming can already be seen in Arctic and alpine areas, where temperatures are rising faster than the global average, and in the oceans, where the combination of rising temperatures and acidification due to increased CO2 concentrations has had catastrophic consequences for sensitive marine organisms inhabiting coral reefs. The scientific papers highlighted as part of this anniversary issue represent some of the most impactful advances in our understanding of the consequences of anthropogenic climate change. Here, we reflect on the legacy of these papers from the biotic perspective.  相似文献   
59.
Fluctuations of bird abundances in the Midwest region of the United States have been attributed to such factors as landscape change, habitat fragmentation, depredation, and supplemental feeding. However, no attempt has been made to estimate the collective role of landowner activities that may influence birds across a landscape. To investigate how landowners might influence birds when the majority (> 90%) of land is privately owned, we surveyed all 1694 private domestic landowners living on three breeding bird survey routes (120 km) that represent a continuum of rural-to-urban landscapes in Southeastern Michigan from October through December 2000. Our survey was designed to investigate (1) the proportion of landowners involved in bird feeding, providing bird houses, planting or maintaining vegetation for birds, gardening, landscaping, applying fertilizer, and applying pesticides or herbicides; (2) whether differences existed between urban, suburban, and rural landowner activities; and (3) whether landowners that carried out a given activity were sociodemographically different from those who did not. Of the 968 respondents (58.5% response rate), 912 (94%) carried out at least one of the activities on their land and the average landowner carried out 3.7 activities. A total of 65.6% fed birds, 45.7% provided bird houses, 54.6% planted or maintained vegetation for birds, 72.7% gardened, 72.3% landscaped, 49.3% applied fertilizer, and 25.2% applied pesticides or herbicides. Significant differences existed between the landscapes, with rural landowners having more bird houses and applying pesticides or herbicides in greater frequency. Similarly, urban landowners had a greater density of bird feeders and houses, but planted or maintained vegetation in the lowest frequency. Participation in activities varied by demographic factors, such as age, gender, and occupation. Scaling each activity to all landowners, including nonrespondents, across all landscapes indicates that between 14% and 82% of landowners may be engaged in a particular activity, with application of pesticides or herbicides having the least potential involvement (13.9%–55.4%) and gardening having the greatest potential involvement (40.1%–81.6%). Taken collectively, our results indicate that landowners are both intentionally and unintentionally engaged in a wide range of activities that are likely to influence bird populations.  相似文献   
60.
Reviews     
Planning theory

Andreas Faludi

Pergamon Press, Oxford, 1973. Hard cover £4.75, flexi‐cover £3.

PLANNING AND THE INNOVATION PROCESS (Progress in Planning, Vol. 1, Part 3)

Ray Jefferson

Pergamon Press, Oxford, 1973

THRESHOLD ANALYSIS MANUAL

Scottish Development Department H.M.S.O., London, 1973. £6

THE PLANNER IN SOCIETY: THE CHANGING ROLE OF A PROFESSION

David Eversley

Faber and Faber, London, 1973. £4.75.

SUB‐REGIONAL PLANNING STUDIES: AN EVALUATION

T. M. Cowling and G. C. Steeley

Pergamon Press, Oxford, 1973. £3.80

SKETCHBOOKS OF PAOLO SOLERI

Paolo Soleri.

M.I.T. Press, Cambridge, Massachusetts & London, England, 1971.

ARCOLOGY: THE CITY IN THE IMAGE OF MAN.

Paolo Soleri.

M.I.T. Press, Cambridge, Massachusetts & London, England, 1969.

FREDERICK LAW OLMSTED AND THE AMERICAN ENVIRONMENTAL TRADITION

Albert Fein

George Braziller, New York. $10.00 cloth. $3.95 paper.

ECOLOGY AND RECLAMATION OF DEVASTED LAND (2 vols.) ed. Russel Hutnick and Grant Davis

Gordon and Breach, New York, 1973. £25.00.

MAN MADE THE LAND: Essays in English Historical Geography

Ed. Alan R. H. Baker and J. B. Harley.

David and Charles, Newton Abbot, 1973. £5.25.

THE UNKNOWN URBAN REALM (Vol. 2, Europe 2,000, Project 3, Urbanization, Planning Human Environment in Europe)

U. Neveling, R. Sulzer, W. Ubbens, G. Wersig.

Martinus Nijhoff, The Hague, 1973.  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