The NO3-N, NO2-N, NH4-N, PO4-P, and Si(OH)4 (dissolved silicate) were analyzed from the filtered water, collected
by a), using Bran Luebbe Auto-Analyzer. The phytoplankton pigments, (chlorophyll-a
and phaeopigments) were analyzed from the filter (GFF). The fluorometry
method was used for this analysis until 1997. Then it was switched to High
Performance Liquid Chromatography (HPLC) method.