3 litres of seawater were collected every 2nd CTD (conductivitiy, temperature and depth) cast on every CTD transect of the BROKE-West voyage. 7 CTD transects were completed on the BROKE-West voyage, all on southwards legs. Samples were collected at 6 depths in the top 200 m of the water column using niskin bottles. 2 litres were filtered through polycarbonate filters and 1 litre was filtered ... through a fibreglass filter. Chemical digestion of the polycarbonate filter enabled us to determine the particulate silicon concentration for each sample (using the nutrient autoanalyser onboard the Aurora Australis, see hydrochemistry section), fibreglass filters have been dried and stored for CHN analysis back on shore.
This work was completed as part of ASAC projects 2655 and 2679 (ASAC_2655, ASAC_2679).