Growth rate and calcium carbonate accumulation of Halimeda macrolobaDecaisne (Chlorophyta: Halimedaceae) in Thai waters

• Main Authors: Jaruwan Mayakun, Patama Bunruk, Rochanakorn Kongsaeng
• Format: Article
• Language: English
• Published: Prince of Songkla University 2014-08-01
• Series: Songklanakarin Journal of Science and Technology (SJST)
• Subjects: calcification; CO2; carbon sink; growth rate; Halimeda macroloba
• Online Access: http://rdo.psu.ac.th/sjstweb/journal/36-4/36-4-5.pdf

Halimeda macroloba Decaisne can utilize the CO2 used for carbon fixation in photosynthesis and use bicarbonate as the main carbon source for calcification. Although Halimeda has been recognized as a carbon sink species, the calcium accumulation of Halimeda species in Thai waters remain poorly understood. In this study, the highest density of H. macroloba was 26 thalli/m2 and Halimeda quickly produced 1-2 new segments/thallus/day or 20.1 mg dry weight/thallus/day. Its calcium carbonate accumulation rate was 16.6 mg CaCO3 /thallus/day, or 82.46 % per thallus. In Thailand, however, only three scientific papers of growth rate and CaCO3 accumulation rate of H. macroloba have been found and collected. Of these records, the mean density was 26-104 thalli/m2 . The growth rate of H. macroloba was around 1-2 mg dry weight/day and the CaCO3 accumulation rate varied around 41-91%. Thus, Halimeda has a great potential to decrease the carbon dioxide concentration in the ocean.