讲座题目：Shelf-break physical-biological interactions off the Cape Cod coast 主讲人：Walker Smith 教授 主持人：吴辉 教授 开始时间：2020-12-15 13:30:00 讲座地址：闵行河口海岸大楼A204会议室 主办单位：河口海岸学国家重点实验室
报告人简介： Walker Smith is a Distinguished Professor at the School of Oceanography, Shanghai Jiao Tong University. He received his Ph.D. at Duke University and studied phytoplankton carbon dynamics in coastal upwelling systems. He was at the University of Tennessee for 22 years, where he pioneered the study of marginal ice zones in the Antarctic and Arctic regions, and then moved to the Virginia Institute of Marine Science (William & Mary), where he continued his work in polar regions. He has conducted biogeochemical research in polar, temperate and tropical regions, and recently participated in SPIROPA, a physical-biological investigation off the east coast of the US. He has published over 250 peer-reviewed articles during his career.
报告内容： A recent field study of the physical-biological interactions at the continental shelf break off the coast of Cape Cod (Massachusetts, USA) revealed a variety of unexpected findings. There was a substantial degree of seasonal variability.In early spring a large bloom of the haptophyte Phaeocystis pouchetii was observed.The bloom originated in shallow waters, and was in large part constrained by a tidal mixing front near Nantucket Shoals. The dynamics of the bloom were documented using a variety of methods: satellites, in situ observations, and continuous measurement of phytoplankton composition. In summer large blooms of diatoms were found in very small layers at the base of the euphotic zone. These layers were driven by the interaction of warm core rings impinging on the bottom, forcing nutrients into the euphotic zone where they were used by a unusual diatom species. These accumulations, while restricted to a few meters in the water column, were major components of water column productivity.Finally, sub-mesoscale features (“streamers”) were observed. These were apparently responsible for a large flux of heat, salt, and organic matter off the continental shelf, and may be a significant feature in biogeochemical budgets of the region. |
