Vietnam waters are located in west of the South China Sea. Due to large area spreading in long latitude with different climate and oceanographic condition, it is very difficult to implement the field measurement in whole water areas for study the natural environment and ecological processes. Some studies on harmful marine micro algal were carried out, but the monitoring the occurrence of algal bloom, especially harmful algal bloom from satellite data was not implemented. This study uses the SeaWiFS satellite data for monitoring the algal bloom occurrence in Vietnam waters during 2002-2004. Chl-a concentration was calculated from SeaWiFS satellite data using OC4 algorithm of SeaDAS software. The study has identified the bloom areas in Vietnam waters during monitoring time. In the Gulf of Tonkin, algae blooms occur at the river mouths where nutrient discharge from rivers is rich. Other areas in the Gulf of Tonkin, the blooms sometimes occurred from November to next April, the same time of Northeast monsoon season. In Central Vietnam waters, the blooms occurred sometimes during Southwest monsoon season from May to September. The observed bloom areas are extended in Northeast direction from Mekong river mouths along the coast, then tendency spread out to off shore where the direction of the coast changes. This bloom occurrence relates to upwelling in Central Vietnam waters. In coastal area of Mekong river delta and Gulf of Thailand, the Chl-a concentration is usually high due to nutrient discharge from rivers. In Paracel Islands, algal bloom is observed in August 2002 and November 2003. Monitoring algae bloom from ocean color satellite data is necessary, especially for warning harmful algal bloom or red tide in Vietnam waters.
雑誌名
Coastal marine science
巻
30
号
1
ページ
44 - 48
発行年
2006-04-28
ISSN
13493000
書誌レコードID
AA11957899
フォーマット
application/pdf
日本十進分類法
452
出版者
International Coastal Research Center, Ocean Research Institute, the University of Tokyo
Using SeaWiFS satellite data for monitoring algal bloom in Vietnam waters, the South China Sea
KJ00004354579.pdf
(848.51KB)
