black sea red data book - Department of Biology

and Mediterranean Seas. Species belonging to inferior northern area. Threatened by
suspended particles, with decreased light penetration for a consequence.
Biology. A perennial plant needing much light; reproduction occurs at a depth
of 0.5-5 m.
Population trends. Almost disappeared! On the Romanian littoral, in the
southern zone of Tuzla-Varna Vech, the biomass of Cystoseira has decreased from
5,4001 fresh weight in 1971 to 755 t in 1973 and 120 t in 1979. The first destruction
came from the freezing of the sea water during the 1971/1972 winter when floating
ice destroyed about 80% of the stock of Cystoseira (900 t in 1972). Currently,
only isolated tufts survive.
Threats. Hard frosts, hydrotechnical constructions, silting of rocky bottoms by
suspended matter, lowering of light energy penetration through the water column by
increased turbidity and eutrophication.
Conservation measures proposed. Reduce eutrophication and pollution from point
and non-point sources; declare the protection of the southern sector of the Romanian
littoral (2 Mai-Varna Veche) as a natural submarine park.
References
Bavaru, A., Bologa A. S. & H. V. Skolka, 1991. A checklist of the benthic marine
algae (except the Diatoms) along the Romanian shore of the Black Sea. Rev. roum.
Biol. biol. veget. 36: 7-22.
Bologa A. S., 1986. Importanta ecológica a algoflorei bentale de la litoralul
Romaniasc al Marii Negre. Hidrobiología 19: 75-82.
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