首页 | 本学科首页   官方微博 | 高级检索  
     检索      


A “horizontal Sverdrup mechanism” may control the spring bloom around small oceanic islands and over banks
Authors:Slv K Eliasen  Eilif Gaard  Bogi Hansen  Karin MH Larsen
Institution:Faroese Fisheries Laboratory, P.O. Box 3051, Tórshavn FO-110, Faroe Islands
Abstract:One of the most basic paradigms in marine ecology is the “Sverdrup mechanism,” where the spring bloom is retarded if the surface mixed layer is too deep, due to the algae being mixed vertically out of the euphotic layer. A similar mechanism may operate in vertically homogeneous water over a small shallow area, surrounded by deep waters, if the horizontal exchange is sufficiently intense. In systems with inter-annual variations in the horizontal exchange rate, this may induce inter-annual variations in the timing and intensity of the spring bloom. A numerical primary production model with circular symmetry and prescribed horizontal exchange rate is developed. Using the Faroe Shelf as an example, the model and observations show that the timing and intensity of the spring bloom in the shallow parts of the system may be critically dependent upon the rate of the horizontal exchange. Numerical experiments confirm that the effect of horizontal exchange on the spring bloom is less pronounced for banks than for shelf systems around islands of similar scales, and that the effect increases in importance as the horizontal scale is reduced.
Keywords:Primary production  Climate  Seafloor topography  Horizontal exchange  Zooplankton  Faroe Shelf
本文献已被 ScienceDirect 等数据库收录!
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号