Nitrogen fixation in the ocean: Present and future scenarios
Impact of climate change (increasing temperature and ocean acidification) on marine carbon cycle is studied extensively. A mesocosm experiment suggested that phytoplankton community consumed 39% more dissolved inorganic carbon at increased pCO2 levels than at present level (Riebesell et al., 2007), however, such an analysis for nitrogen cycle is missing. Such N2 fixation studies are a few and these are limited to culture experiments (e.g., Levitan et al., 2007), which may not be a clear representative of response of oceanic community structure to climate change. Given the anticipated changes in the environment parameters, the relative importance of changes in pCO2, sea surface temperature, salinity and atmospheric dust deposition on nitrogen fixation needs to be further assessed on natural community in the context of the future ocean. Therefore, this project aims to understand N2 fixation in the ocean for present and future climatic conditions.
