全文获取类型
收费全文 | 194篇 |
免费 | 1篇 |
国内免费 | 3篇 |
专业分类
测绘学 | 5篇 |
大气科学 | 8篇 |
地球物理 | 84篇 |
地质学 | 51篇 |
海洋学 | 29篇 |
天文学 | 15篇 |
综合类 | 1篇 |
自然地理 | 5篇 |
出版年
2022年 | 1篇 |
2020年 | 1篇 |
2019年 | 1篇 |
2015年 | 1篇 |
2013年 | 1篇 |
2012年 | 4篇 |
2011年 | 21篇 |
2010年 | 1篇 |
2008年 | 15篇 |
2007年 | 11篇 |
2006年 | 10篇 |
2005年 | 12篇 |
2004年 | 8篇 |
2003年 | 8篇 |
2002年 | 10篇 |
2001年 | 4篇 |
2000年 | 10篇 |
1999年 | 3篇 |
1998年 | 2篇 |
1997年 | 5篇 |
1996年 | 7篇 |
1995年 | 16篇 |
1994年 | 7篇 |
1993年 | 5篇 |
1992年 | 11篇 |
1991年 | 4篇 |
1990年 | 9篇 |
1989年 | 7篇 |
1988年 | 1篇 |
1987年 | 1篇 |
1984年 | 1篇 |
排序方式: 共有198条查询结果,搜索用时 15 毫秒
121.
Kelley MA Gillespie A Zhou GD Zhang S Meador JP Duncan B Donnelly KC McDonald TJ 《Marine pollution bulletin》2011,62(11):2520-2532
Contaminated sediments may have wide-ranging impacts on human and ecological health. A series of in situ caged exposure studies using juvenile Chinook salmon was conducted in the Lower Duwamish Waterway (LDW). Chemical analysis of sediment, water, and fish tissue were completed. Additionally, in 2004, DNA adducts in hepatic and gill tissues were measured. Gills contained significantly higher DNA adducts at stations B2 and B4, prompting further analysis of gills in 2006 and 2007. Fluorescent aromatic compounds (FACs) in bile, and CYP1A1 in hepatic tissue were also measured during 2006 and 2007, respectively. FACs in field-caged fish were comparable or significantly higher than wild-caught fish LDW fish and significantly higher than lab fish after only 8-10 days, demonstrating the equivalency of exposure to that of migrating salmon. Furthermore, selected biomarkers appear to be capable of detecting spikes in contamination between sampling years, emphasizing the need for multiple year data collection. 相似文献
122.
Cohu S Thibaut T Mangialajo L Labat JP Passafiume O Blanfuné A Simon N Cottalorda JM Lemée R 《Marine pollution bulletin》2011,62(12):2681-2691
To study environment characteristics favoring the toxic benthic dinoflagellate Ostreopsis cf. ovata, a survey was conducted in Monaco (NW Mediterranean Sea), in summers 2007 and 2008. Epiphytic and planktonic blooms occurred almost simultaneously and a high variation of abundances at low spatial scales was observed. An early and very marked bloom occurred in 2007, compared to a later and less abundant development in 2008. These distinct patterns in bloom timing corresponded with very different hydroclimatic scenarios in 2007 (hot spring and relatively cold summer) and 2008 (standard year compared to the median year profile estimated with data from 1995 to 2008). No clear impacts of summer seawater temperature, rainfall or nutrient concentrations were evident. Strong wind may favor the dispersal of benthic and planktonic cells. Our study suggests that further investigations are needed to examine the potential role of Ostreopsis nutritional mode (i.e. autotrophy vs. mixotrophy). 相似文献
123.
Management of the marine environment: integrating ecosystem services and societal benefits with the DPSIR framework in a systems approach 总被引:4,自引:0,他引:4
Ever increasing and diverse use of the marine environment is leading to human-induced changes in marine life, habitats and landscapes, making necessary the development of marine policy that considers all members of the user community and addresses current, multiple, interacting uses. Taking a systems approach incorporating an understanding of The Ecosystem Approach, we integrate the DPSIR framework with ecosystem services and societal benefits, and the focus this gives allows us to create a specific framework for supporting decision making in the marine environment. Based on a linking of these three concepts, we present a set of basic postulates for the management of the marine environment and emphasise that these postulates should hold for marine management to be achieved. We illustrate these concepts using two case studies: the management of marine aggregates extraction in UK waters and the management of marine biodiversity at Flamborough Head, UK. 相似文献
124.
Wang T Lu Y Chen C Naile JE Khim JS Park J Luo W Jiao W Hu W Giesy JP 《Marine pollution bulletin》2011,62(8):1905-1914
Perfluorinated compounds (PFCs) in water, sediment, soil, and biota collected from estuarine and coastal areas of the north Bohai Sea, China, were determined by use of HPLC-MS/MS. Significant concentrations of PFCs were found in water (mean: 18.4 ng/l) and biologic samples (fish: 265 ng/g dw), while concentrations of PFCs in soils and sediments were less. The predominately detected compound was perfluorooctanesulfonate (PFOS), with a maximum concentration of 30.9 ng/l in water and 791 ng/g dw in fish. Concentrations of PFCs were significantly greater in the Liaohe River system than other locations, which suggests point sources in this urbanized and industrialized region. PFOS concentrations in water and biota were both less than the reported threshold concentrations. Detection of PFCs at relatively great concentrations in various environmental matrices from this region suggested that further studies characterizing concentrations of PFCs, their sources and potential risk to both humans and wildlife are needed. 相似文献
125.
126.
Aliphatic and aromatic hydrocarbons in coastal Caspian Sea sediments 总被引:17,自引:0,他引:17
Tolosa I de Mora S Sheikholeslami MR Villeneuve JP Bartocci J Cattini C 《Marine pollution bulletin》2004,48(1-2):44-60
This investigation represents the first extensive study of the spatial distribution and sources of aliphatic (n-alkanes and unresolved complex mixture of fossil hydrocarbons) and polycyclic aromatic hydrocarbons (PAHs) in coastal sediments from the Caspian Sea. PAH concentrations, n-alkanes and biomarker profiles all suggested that there was limited petrogenic contamination in the shallow North Caspian Sea sediments, which are coarse with a low total organic carbon content. In contrast, moderate to high petrogenic contamination was found in the South Caspian Sea, in particular in the offshore oil fields near Baku, Azerbaijan. Contaminant patterns indicated that the PAHs were mainly from fossil sources, with higher contributions of pyrolytic only near industrialized and urban areas. A high contribution of perylene, a geochemically derived PAH, to the total PAHs was found in the west and south at sites influenced by the Kura, Safid Rud, Terek, Sulak and Samur Rivers. 相似文献
127.
蔡建华 《国土资源导刊(湖南)》2003,22(1):58-60
三重管高压喷射注浆就是采用分别输送水、气和浆液3种工作介质的三重注浆管,使高压水、压缩空气冲击破坏土体,再让水泥浆液与土体搅拌混合,形成渗透系数为10-7cm/s的固结体的岩土施工方法.它分为定喷和旋喷两种形式,适宜于地基加固和基础防渗. 相似文献
128.
129.
Coelho JP Pimenta J Gomes R Barroso CM Pereira ME Pardal MA Duarte A 《Marine pollution bulletin》2006,52(6):674-680
The focus of this work is to explore the use of the netted whelk, Nassarius reticulatus (L.), as an indicator of mercury (Hg) contamination, by assessing the concentration of Hg in the sediments and in the whelk along the entire Portuguese coast. Total Hg concentrations ranged from below the detection limit (0.01 ng absolute mercury) up to 0.87 mg kg(-1) dry weight (dwt) in sediments and between 0.06 and 1.02 mg kg(-1) (dwt) for organisms, with no significant differences between males and females. Although organic mercury was not detected in the sediments, it represented, on average, 52% of the total Hg in the whelk tissues, and as high as 88% in some cases, suggesting mercury accumulation from dietary intake. Significant negative correlations were found between the total Hg concentrations in the sediments and the log(10) of Hg concentrations in whelk tissues males (r=-0.64; P<0.01) and females (r=-0.52; P<0.01) indicating that the species is a poor indicator of Hg contamination. Nevertheless, since the highest concentrations of organic mercury in the whelk tissues were found in the least contaminated areas, this species must be highly relevant in the trophic web, namely on the possible biomagnification of mercury. The high dietary mercury accumulation from feeding on carrion and the low bioavailability of mercury to whelks in estuarine sediments may be the basis of the mercury accumulation pattern in N. reticulatus. 相似文献
130.
Bouchet VM Debenay JP Sauriau PG Radford-Knoery J Soletchnik P 《Marine environmental research》2007,64(3):358-383
Sediment cores were collected from April to August 2004 on tidal mudflats of the macrotidal Marennes-Oléron Bay (SW France), famous for the cultivation of Pacific oysters (Crassostrea gigas). The response of living (stained) benthic foraminifera to short-term biogeochemical disturbances in the sediment and overlying water, which may be involved in oyster summer mortality, was monitored. Short-term hypoxia occurred in early June, in conjunction with a sudden rise in temperature. In mid-June, the ammonia content of sediment porewater increased, leading to potentially maximal flux towards overlying waters. Foraminiferal assemblages, particularly in the topmost layer, were altered. Ammonia tepida was the most tolerant to temperature increase and hypoxic conditions whereas Brizalina variabilis and Haynesina germanica were sensitive to organic degradation and hypoxia. Cribroelphidium gunteri was the most opportunistic during recolonisation. Benthic foraminifera showed that short-term biochemical changes in the sediment are toxic and may be involved in the summer mortality of Pacific oysters. 相似文献