Turkish Journal of Fisheries and Aquatic Sciences
2014, Vol 14, Num, 5 (Pages: 955-964)
Microzooplankton: The Trophic Role and Involvement in the Phytoplankton Loss and Bloom-Formation in the Black Sea
Lyudmyla Stelmakh 1-2 ,Elena Georgieva 1-2
1 Southern Seas (IBSS) National Academy of Sciences of Ukraine, A.O. Kovalevsky Institute of Biology, Sevastopol, Nakhimov Av., 2, Ukraine
DOI :
10.4194/1303-2712-v14_4_15
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For the first time microzooplankton grazing impact on phytoplankton in the Black Sea was investigated in relation to
seasonal and spatial variability. In this work we used scientific evidence obtained in the experiments conducted in the
Sevastopol Bay (2006-2010) and in field during the Black Sea expeditions of the R/V "Vladimir Parshin" (September-October
2005) and the R/V "Professor Vodyanitsky" (May 2013). In the Sevastopol Bay the ratio between microzooplankton grazing
impact and specific rate of phytoplankton growth (g/μ) yielded the annual average of 65% that agrees with the annual average
for phytoplankton primary production consumed by microzooplankton. It was found that, irrespective of the location, with
sufficient quantity of nutrients in the stratified sea water, phytoplankton blooms began to form as the ratio between
microzooplankton grazing and phytoplankton growth rates (g/μ) was ≤75%; as the bloom was ceasing, the ratio was evaluated
>100%. Therefore, we suppose, that initiation of phytoplankton blooms is possible when conditions are favorable for rapid
phytoplankton growth and the ratio of grazing to growth (g/μ) will be <75%.
Keywords :
Phytoplankton bloom, growth rate, microzooplankton grazing, Black Sea