4SEAS

Phytoplankton - microalgae – unicellular planktonic plants – can be seen only through microscope. But though so tiny they play the magnificent role in our own life, and in the life of the planet EARTH.

MICROALGAE are PHOTOTROPHS, that means that they feed themselves synthesizing organic matter using the energy of the sun, different mineral components, among them nitrogen and phosphorus most important, and due to this process oxygen is produced. The photosynthesis mechanism they use is the most effective and widespread on the Earth where it exist almost about 3,5 milliards of years. Oxygen atmosphere of Earth emerged first due to the activities of these tiny creatures, and still the O2/CO2 balance depends on their activities . They produce enormous quantity of organic matter (PRIMARY PRODUCTION) - the basis for ALL MARINE PRODUCTIVITY.
Phytoplankton exist everywhere in the seas where the light needed for photosynthesis can penetrate. Sometimes there are few cells in the seawater, but when nutrients, light and temperate are fav

orable for microalgae they can “bloom” up to millions in one ml. And then we can see them by naked eye: not the cells of cause but the color of water: green, red, brown, yellow…”Red tides” are called so because of color of microalgae bloom.
Black Sea waters are inhabited by one third of microalgae species inhabiting the World Ocean, about 600 species.
Most variable among them are dinoflagellates (40 % of the total number of species found in the Black Sea).
Dinoflagellates could be considered the biggest forms of microalgae in the Black Sea.
The group of dinoflagellates is so amazing, that still not all the scientists have the same opinion, whether they should be considered plants, or partly animals. The problem is that most of them are able to photosynthesize but not only. Some can use organic matter, and several of the can graze on bacteria, or even microalgae (Oxyrrhis sp.). Some of them can even phagocytize. Certain species are undoubtedly animals - Noctiluca, or “night light”, which is very abundant and very bioluminescent species. Large noctilucas as big as the fish eggs can graze not microalgae but ciliates, and other animals. But the main part of dinoflagellates are typical microalgae.
“Dino-Flagellate” means “armoured flagellate” in Greek. Indeed their cell is robed as if a chivalry encased in armor. This “armor” mainly consists from cellulose.
During start of spring among the Black Sea phytoplankton can be seen the big cells with double random processes, moving smoothly towards one direction, then suddenly changing to another, swiveling heavily but yet very graceful. Those are the cells of different Ceratiums. They bioluminescent but their light could be registered only by special instruments. In late spring rather big, leaves-like cells Prorocentrum micans can be rather abundant.
When dinoflagellates are abundant in the water, the skilled researcher can even distinguish their presence by naked eye due to their specific movements. Dinoflagellates are moving very gracefully, advancing spirally, or gyre-like as if threading into the water twirling around own axe. Such movement is possible due to the tireless beating of 2 different flagellas, hidden in the groves of dinoflagellates’ armor. One - as if twisted around dinoflagellate’s waist, another – moving in body’s vangaurd
Have a look yourself on the dinoflagellates dance!
You are welcome to the world of phytoplankton guided by our new video!