A Sulfur Hexafluoride-Based Lagrangian Study on Initiation and Accumulation of the Red Tide Cochlodinium in Southern Coastal Waters of Korea
Abstract
During the last two decades, massive accumulations of autotrophic algae and some heterotrophic protists, collectively referred to as harmful algal blooms (HABs), have increased considerably in frequency, size, and cell density across the globe. Several field studies suggest increasing eutrophication as the primary reason for the increases in the blooms; however, strong evidence for this relation is not yet available, largely due to the ephemeral and complex nature of HABs. Here we report the first continuous in situ measurements of a population of the HAB species C. polykrikoides in a fixed volume of inshore waters near the island of Naro-do (34.47° N and 127.55° W), an area that lies off the southern coast of Korea and where the first bloom of C. polykrikoides has occurred at least for each of the past five years. This Lagrangian experiment was carried out by injecting the inert chemical tracer sulfur hexafluoride (SF6) into a patch of seawater carrying C. polykrikoides and tracking the SF6-labeled water mass for 4 days. Our results suggest that bloom initiation and much of the cell accumulation in the early phase of the bloom are due to the input of C. polykrikoides cells from a shoreward movement of alongshore currents.
- Publication:
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AGU Fall Meeting Abstracts
- Pub Date:
- December 2004
- Bibcode:
- 2004AGUFMOS33D..05P
- Keywords:
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- 4845 Nutrients and nutrient cycling;
- 4853 Photosynthesis;
- 4855 Plankton;
- 4894 Instruments and techniques;
- 4235 Estuarine processes