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M.F. Lavín P.C. Fiedler J.A. Amador L.T. Ballance J. Frber-Lorda A.M. Mestas-Nuez 《Progress in Oceanography》2006,69(2-4):391
The collection of articles in this volume reviewing eastern tropical Pacific oceanography is briefly summarized, and updated references are given. The region is an unusual biological environment as a consequence of physical characteristics and patterns of forcing – including a strong and shallow thermocline, the ITCZ and coastal wind jets, equatorial upwelling, the Costa Rica Dome, eastern boundary and equatorial current systems, low iron input, inadequate ventilation of subthermocline waters, and dominance of ENSO-scale temporal variability. Remaining unanswered questions are presented. 相似文献
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1980—1993年对黄茅海河口湾进行沉积物采样和水流测定及水深测量。根据水动力和地形条件,冲淤分析及Mclaren模型研究河口湾的动力地貌体系、冲淤特征和现代沉积物运移。结果表明:(1)水下地形主要为下泄流或上溯流控制的“深槽-槽沟-浅滩-湾口”的动力地貌体系,反映了河口湾“东进西出”的水流格局;(2)整个河口湾以淤积为主,只有崖门深槽有较明显的优势冲刷特征,并随着崖门深槽向海推移和河口湾“东进西出”水动力作用,黄茅海落潮三角洲相应向西南进积;(3)应用Mclaren模型揭示了黄茅海河口湾现代沉积物运移规律,同样反映了河口湾具有“东进西出”的运移趋势。 相似文献
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A study of an expanding seagrass bed on the south-west coast of British Columbia, Canada involved documentation and explanation of the pattern of expansion of the vegetation as well as documentation and experimental investigation of the accompanying changes in the distribution of infaunal invertebrates. Expansion followed a major environmental change, improved water clarity initiated in 1969 when a causeway blocked access to the site for silty Fraser River water. The original eelgrass (Zostera marina) bed expanded landward over 30 m year−1, probably causing more and more water to be retained in the bed at low tide and thus improving its own habitat. More rapid expansion occurred from 1979–1983 after Z.japonica colonized at the landward edge of the eelgrass bed and in a separate intertidal area. Expansion ceased around 1983 coincident with, but probably independent of, further construction.Burrowing shrimp (Callianassa californiensis) decreased in abundance between 1977 and 1984 in areas where the two seagrasses colonized. Short-term experiment over one summer and fall showed that removal of all shoots allowed adult shrimp and tube worms to colonize the sediment while addition of shoots of Z. japonica by transplanting caused temporary decreases in shrimp abundance. After a few weeks an established shrimp population destroyed the transplants. Among reasonable alternate hypotheses for the decline in Callianassa, the effect of sediment texture can be eliminated, but either direct negative effects of seagrass, i.e. inhibition of the burrowing of adult shrimp or of settlement of juveniles, or indirect effects, i.e. the harboring of more predators of shrimp in seagrass beds, deserve further study. 相似文献
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INTRODUCTIONTheDenglouCape ,inthesouthwestoftheLeizhouPeninsula ,isatthenorthmarginoftropicalzone .SeveralresearchesandcartographiesoftheregionalgeomorphologyandQuater narygeology ,whichwerecarriedoutinthepast,allincludethisarea (MGL ,SCSIO ,CAS ,1 978;GPCSGRCZT… 相似文献
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Abstract. Biokarst-forms on limestone coasts are developed and arranged according to the bionomic zonation. The development of biokarst is the result of bioerosion, a synergistic effect of biological corrosion by endoliths and biological abrasion by grazers.
The cumulative effect of biogenic carbonate destruction leads to coastal destruction with a resulting highly profiled morphology on the limestone surfaces along the coastal profile. Under the influence of environmental factors a zonation of organisms develops which brings in turn a zonation of erosion rates (0.1-1.1 mm a-1 ) resulting in biokarst-forms such as rock holes, rock pools and notches.
Products of bioerosion on limestone coasts are dissolved carbonate (by biological corrosion, 10–30% of the decomposed limestone) and particulate carbonate (by biological abrasion, 70–90% of the decomposed limestone) both of which contribute directly or indirectly to nearshore sedimentation. Size and shape of the bioerosional grains are determined by the boring pattern of the endoliths. The fine-grained sediments (maximum within the fraction 20–63 μm) contribute 3–25 % to the nearshore sediments.
Drastic changes in the biological zonation (like the mass invasion of the sea urchin Paracentrotus lividus in the Northern Adriatic since 1972 which eliminated nearly the entire macrophyte zone) due to unknown factors or pollution can have a profound effect on the bioerosion rates, altering them by as much as a factor of ten. 相似文献
The cumulative effect of biogenic carbonate destruction leads to coastal destruction with a resulting highly profiled morphology on the limestone surfaces along the coastal profile. Under the influence of environmental factors a zonation of organisms develops which brings in turn a zonation of erosion rates (0.1-1.1 mm a
Products of bioerosion on limestone coasts are dissolved carbonate (by biological corrosion, 10–30% of the decomposed limestone) and particulate carbonate (by biological abrasion, 70–90% of the decomposed limestone) both of which contribute directly or indirectly to nearshore sedimentation. Size and shape of the bioerosional grains are determined by the boring pattern of the endoliths. The fine-grained sediments (maximum within the fraction 20–63 μm) contribute 3–25 % to the nearshore sediments.
Drastic changes in the biological zonation (like the mass invasion of the sea urchin Paracentrotus lividus in the Northern Adriatic since 1972 which eliminated nearly the entire macrophyte zone) due to unknown factors or pollution can have a profound effect on the bioerosion rates, altering them by as much as a factor of ten. 相似文献
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一种新型经济海藻--冈村枝管藻 总被引:7,自引:1,他引:7
介绍了1种新型经济海藻冈村枝管藻。阐明了引进新型经济海藻,对进一步发展我国海藻栽培业的经济意义和生态意义,综述了该物种的生物学特性、栽培和加工情况、应用价值,以及作者在这方面初步的研究工作,并展望了在我国发展枝管藻栽培业的前景。 相似文献