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1.
Radiocaesium isotopes, discharged into the North-east Irish Sea from the Sellafield (formerly Windscale) nuclear fuel reprocessing plant in Cumbria, have been employed as flow monitors to update and extend the record of coastal water movement from the Irish Sea to the Clyde Sea area and, further north, to Loch Etive. The temporal trends in radiocaesium levels have been used to determine the extent of water mixing en route and to define mean advection rates. Flow conditions from the Irish Sea have changed considerably since the mid-1970s, the residence time of northern Irish Sea waters being ~12 months during 1978–1980 inclusive. Average transport times of four and six months are estimated for the Sellafield to Clyde and Sellafield to Etive transects respectively. Sellafield 137Cs levels in seawater were diluted by factors of 27 and 50 respectively during current movement to the Clyde and Etive areas. The decrease in salinity-corrected 137Cs concentrations between the Clyde and Etive suggests that dilution by Atlantic water occurs, the latter mainly entering the Firth of Lorne from the west. The majority (~94%) of the radiocaesium supply to Loch Etive enters the Firth of Lorne via the portion of the coastal current circulating west of Islay, only ~6% arriving via the Sound of Jura. 相似文献
2.
Prosper?L.?Mfilinge Tarik?Meziane Zainudin?Bachok Makoto?TsuchiyaEmail author 《Journal of Oceanography》2005,61(3):613-622
Changes in the concentration of total lipid and fatty acids (FAs) during the decomposition of mangrove leaves were investigated by field experiments using yellow leaves of Bruguiera gymnorrhiza (L.) Lamk. and Kandelia candel (L.) Druce, in order to quantify mangrove contribution to lipid and fatty acid inputs to marine sediments. Total lipid and total FA in the fresh (green and yellow) and decomposing leaves of both species were significantly higher during winter than summer. During decomposition, total lipid content and FA concentration, in particular branched chain fatty acids (BrFAs) and bacterial fatty acids (BFAs), increased to a maximum concentration in 45 days during winter and in 17 days during summer. Lipids were lost faster in K. candel leaf detritus than in B. gymnorrhiza leaf detritus in which >90% of the total lipid original weight was lost during the summer experiment and <60% during the winter experiment. The changes in the concentrations of total lipids and FAs in the decomposing leaves also indicate that mangrove leaves are significant sources of fatty acids and probably other lipid compounds to estuarine ecosystems and that tidal waters transport the lipids and FAs adsorbed to particulate matter from mangroves to adjacent estuarine sediments and the ocean. 相似文献
3.
Jan Kohlmeyer 《Marine Ecology》1984,5(4):329-378
Abstract. Marine Ascomycetes, Basidiomycetes and Deuteromycetes were collected in tropical and subtropical regions (Australia, Belize, Fiji, Hawaii, Marshall Islands, Mexico, New Zealand, Palau, Thailand), and the known range of distribution for these fungi was extended. Exclusively tropical are 27 taxa, 9 are probably restricted to the tropics also, and 11 are cosmopolitan. Distribution maps are given for 5 taxa. New species (4), varieties (3), and combinations (2) of Ascomycetes are proposed, and keys to the taxa of Halosarpheia and Lulworthia are presented. Most of the species are decomposers of mangrove parts or of detritus in sandy beaches. Nine new host plants were found. Marine Ascomycetes were discovered for the first time living in shells of foraminifera. 相似文献
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青岛浮山野生花卉种质资源 总被引:2,自引:0,他引:2
本文简要叙述了青岛浮山野生花卉的种类、生长环境、园林用途及开花结果日期,为把这些野生花生花卉引进城市园林提供科学依据。 相似文献
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XU Qingyan WANG Jianfeng HUANG Yaojian ZHENG Zhonghui SONG Siyang ZHANG Yongmin SU Wenjin 《海洋学报(英文版)》2004,23(3):541-547
Mangroves are special woody plant communities in the intertidal zone of tropical and subtropical coasts. They prove to be a natural microorganisms and new metabolites storage. In the study of mangrove endophytic fungi metabolites, four new compounds, Compounds 1, 2, 3 and 4, as well as a known octaketide, cytosporone B (5), are isolated from an endophytic fungus, Dothiorella sp., HTF3. They all show cytotoxic activities. The elucidation of these structures is mainly based on 1D/2D NMR and ESI-MS spectral analyses. 相似文献
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Vegetation change and surface elevation dynamics in estuarine wetlands of southeast Australia 总被引:1,自引:1,他引:1
Vertical accretion and surface elevation trends were studied in mangrove and saltmarsh wetlands in southeast Australia. A total of 69 surface elevation tables, each associated with three feldspar marker horizons, was deployed in 10 wetlands across 7 estuaries, and monitored for three years. Saltmarsh and mangrove vegetation distributions were mapped for the same estuaries, and elevation characteristics of the wetlands were modelled. Rates of vertical accretion were found to correlate with tidal range. No relationship was found between rates of vertical accretion and surface elevation increase. A positive relationship was demonstrated between contemporary rates of saltmarsh surface elevation change and longer-term rates of mangrove encroachment into saltmarsh. We conclude that landward mangrove encroachment may be facilitated by local factors contributing to saltmarsh compaction during drought conditions. 相似文献
10.
INTRODUCTIONTheDenglouCape ,inthesouthwestoftheLeizhouPeninsula ,isatthenorthmarginoftropicalzone .SeveralresearchesandcartographiesoftheregionalgeomorphologyandQuater narygeology ,whichwerecarriedoutinthepast,allincludethisarea (MGL ,SCSIO ,CAS ,1 978;GPCSGRCZT… 相似文献