Job Description: Four MSc’s, two PhD’s and one Post Doctorate opportunity in the SOCCO iron project
Introduction:There is now unequivocal evidence that the micronutrient iron and iron-light co-limitation are the primary limiting factors of phytoplankton production in the Southern Ocean. This effectively controls the strength of the efficiency of the 'biological carbon pump', which exports fixed carbon into the deep ocean and so influences atmospheric CO2 concentration. This is due to low dFe concentrations (<1.0nmol), low solubility in oxygenated seawater at normal pH and low inputs to the Southern Ocean from continental shelfs. Iron is an essential element for phytoplankton growth, as it occurs and is needed in different metabolic processes, such as in the photosynthetic and respiratory electron transport system, reduction of nitrates and phosphates, nitrogen and carbon dioxide fixation and the synthesis of chlorophyll. The net impact of Fe on overall primary productivity requires quantifying dFe supply and dFe demand on phytoplankton photosynthetic rates and on nitrogen uptake rates under variable light regimes also taking into consideration phytoplankton community structure. Clearly resolving this complex matrix of interdependent processes as a function of environmental variability (seasonal, regional and longer-term) necessitates a multi-disciplinary approach.
Study 1:One MSc project assisting with high depth resolution measurements of dFe in winter to characterize the dFe profile and high depth and time resolution dFe profiles in summer to investigate the sub-seasonal supply of Fe to surface waters through transient mixing and re-stratification events. The dFe supply and demand will be interpreted in conjunction with measurements of phytoplankton biomass, community structure and productivity.