Seasonal changes of primary production along the south-eastern coasts (Artvin-Giresun) of the Black Sea

In the present study, seasonal changes of size fractioned primary production (picoplankton, <0.2-2µm; nanoplankton, 2-10 µm; mikroplankton, >10 µm) in autumn (November 2014), winter (February 2015), spring (May 2015) and summer (August 2015) along the south-eastern Black Sea (Artvin-Giresun) ecosystem were investigated. Along the 12 stations (Giresun 2 miles, Giresun 8 miles, Trabzon 2 miles, Trabzon 8 miles, Trabzon 15 miles, Çamburnu 2 miles, Çamburnu 8 miles, Pazar 2 miles, Pazar 8 miles, Pazar 15 miles, Kemalpaşa 2 miles, Kemalpaşa 8 miles) seasonal samplings were conducted from surface to 40 m depths with 10 m intervals. C-14 experiments revealed that primary production ranged from 295 mgCm2 to 5931 mgCm2 along the stations. Considering phytoplankton size classes, size fractioned primary production ranged from 119 to 1848 mgCm2, from 96 to 3156 mgCm2 and from 73 to 3363 mgCm2 for picoplankton, nanoplankton and microplankton, respectively. In terms of season, the contribution of microplankton and nanoplankton were prominent in spring. During summer and autumn, picoplankton and nanoplankton were characterised with high contribution of primary production. In terms of stations, coastal stations had higher primary production rates.