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101.
Jackson JB Cubit JD Keller BD Batista V Burns K Caffey HM Caldwell RL Garrity SD Getter CD Gonzalez C Guzman HM Kaufmann KW Knap AH Levings SC Marshall MJ Steger R Thompson RC Weil E 《Science (New York, N.Y.)》1989,243(4887):37-44
In 1986 more than 8 million liters of crude oil spilled into a complex region of mangroves, seagrasses, and coral reefs just east of the Caribbean entrance to the Panama Canal. This was the largest recorded spill into coastal habitats in the tropical Americas. Many population of plants and animals in both oiled and unoiled sites had been studied previously, thereby providing an unprecedented measure of ecological variation before the spill. Documenation of the spread of oil and its biological begun immediately. Intertidal mangroves, algae, and associated invertebrates were covered by oil and died soon after. More surprisingly, there was also extensive mortality of shallow subtidal reef corals and infauna of seagrass beds. After 1.5 years only some organisms in areas exposed to the open sea have recovered. 相似文献
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Nadeau JH Balling R Barsh G Beier D Brown SD Bucan M Camper S Carlson G Copeland N Eppig J Fletcher C Frankel WN Ganten D Goldowitz D Goodnow C Guenet JL Hicks G Hrabe de Angelis M Jackson I Jacob HJ Jenkins N Johnson D Justice M Kay S Kingsley D Lehrach H Magnuson T Meisler M Poustka A Rinchik EM Rossant J Russell LB Schimenti J Shiroishi T Skarnes WC Soriano P Stanford W Takahashi JS Wurst W Zimmer A;International Mouse Mutagenesis Consortium 《Science (New York, N.Y.)》2001,291(5507):1251-1255
103.
Jackson HH 《Science (New York, N.Y.)》1914,39(1006):534-535
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Effects of basal debris on glacier flow 总被引:1,自引:0,他引:1
Iverson NR Cohen D Hooyer TS Fischer UH Jackson M Moore PL Lappegard G Kohler J 《Science (New York, N.Y.)》2003,301(5629):81-84
Glacier movement is resisted partially by debris, either within glaciers or under glaciers in water-saturated layers. In experiments beneath a thick, sliding glacier, ice containing 2 to 11% debris exerted shear traction of 60 to 200 kilopascals on a smooth rock bed, comparable to the total shear traction beneath glaciers and contrary to the usual assumption that debris-bed friction is negligible. Imposed pore-water pressure that was 60 to 100% of the normal stress in a subglacial debris layer reduced shear traction on the debris sufficiently to halt its deformation and cause slip of ice over the debris. Slip resistance was thus less than debris shearing resistance. 相似文献
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The gradual closure of the Panamanian seaway and the resulting environmental change stimulated an increase in Caribbean molluscan diversity rather than the mass extinction hypothesized previously on the basis of inadequate data. Upheaval of molluscan faunas did occur suddenly throughout tropical America at the end of the Pliocene as a result of more subtle, unknown causes. There is no necessary correlation between the magnitude of regional shifts in abiotic conditions and the subsequent biological response. 相似文献