Asian Journal of Microbiology, Biotechnology & Environmental Sciences Paper

CARBON CAPTURE AND SEQUESTRATION POTTENTIAL OF CHAETOCEROS SP. IN IRON RICH GROUND WATER

K. SWAMINATHAN AND P. THAMARAI

Abstract

Carbon sequestration using phytoplanktons in the world oceans is one of the wise options to mitigate global warming. The increased growth of phytoplanktons would consume more carbon di oxide and thus much of the carbon can be sequestrated in the oceans. However, the less availability of iron over large areas of the ocean limits primary productivity by phytoplanktons and the associated uptake of carbon. And hence, iron fertilization in the marine environment is used to improve the growth and carbon uptake potentials of phytoplanktons. Usually various sources of irons are being tested for their efficiency in enhancing the growth of phytoplanktons in the oceans. Here, for the first time the natural iron rich groundwater is used as an iron source to increase the growth and carbon sequestration potential of marine phytoplankton (Chaetoceros sp.) in vitro. Our in vitro studies concluded that iron at not less than 3 ppm concentration was found to enhance the growth of selected phytoplankton Chaetoceros sp. Iron rich ground water as a source of iron (5 ppm) in f/2 medium has remarkably enhanced the growth (OD 0.208 @ 620nm) and fresh (0.244 g) and dry weight (0.007 g) of the selected phytoplankton. In order to demonstrate the effect of phytoplankton growth on the carbon sequestration, the growth of algae and the content of chlorophyll, protein, total carbohydrate and total organic carbon were estimated. At highest concentration of iron in the form of iron rich ground water in the growth medium has increased the content of chlorophylls, intra and extra cellular proteins, total carbohydrate content. Moreover, the iron supply has enhanced the total organic carbon in the algal biomass which indicates that enhancing carbon sequestration by Chaetoceros sp. (phytoplankton) is possible while using natural iron rich ground water as the source of iron.