spring, the effect of the air temperature variations upon С Chl was insignificant. The
Danube discharge impact was more noticeable. In summer, 2005–2015, in both
NWBS areas air temperature increase and the С Chl decrease were observed.
The inter-annual variability patters of the chlorophyll a concentration in the
Romanian and the Bulgarian coastal areas coincided satisfactorily. The correlation
coefficients of the С Chl series in these regions in the spring-autumn period were
rather high (0.7–0.8). The low correlation coefficient, 0.35, was obtained only for
the winter period. The Danube discharge effect on the inter-annual variations of the
chlorophyll a concentrations in the Romanian and the Bulgarian areas was assessed
by the degree of connection between its seasonal concentrations in the Danube area
and in these two ones. The correlation coefficient of С Chl in the Danube and the
Romanian areas in the spring-summer period was equal to 0.7, and in autumn – 0.6.
It testifies to the fact that the phytoplankton bloom and variability in these areas are
affected by the similar factors, one of which is the riverine discharge. In the
Bulgarian area the Danube discharge produces a weaker effect upon the phytoplankton bloom as compared to the Romanian area. This effect is manifested only
in the spring summer period when the transformed river waters flow into the area.
References
Aubrey D, Moncheva S, Demirov E (1996) Envirommental changes in the Western Black Sea
related to anthropogenic and natural conditions. J Mar Syst 7:411–425
Bodeanu N (1992) Algal blooms and development of the main phytoplanktonic species at the
Romanian Black Sea littoral in conditions of intensification of the eutrophication process. In:
Science of the total environment. Elsevier Science Publisher, Amsterdam, pp 31–50
Bodeanu N, Moncheva S, Ruta G, Popa L (1998) Long-term evolution of the algal blooms in
Romanian and Bulgarien Black Sea waters. Cercetari marine – Recherches marines 31:37–55
Bol’shakov VS (1970) Transformation of the river waters in the Black Sea. Naukova Dumka,
Kiev, p 328 (in Russian)
Bologa AS (1977) The phytoplanktonic assimilatory pigments along the Romanian coast of the
Black Sea during 1976. Cercetari marine – Recherches marines 10:95–107
Bologa AS (1978) The monthly dynamics of phytoplanktonic assimilatory pigments from the
sector Conztantza – Agigea of theRomanian Black Sea coast during 1977. Cercetari marine –
Recherches marines (11):77–83
Bologa AS (1985/1986) Planktonic primary productivity of the Black Sea. Thalass Jugosl 21
(22):11–22
Bologa AS (1992) Review of the state of environment and biological changes in Romanian Black
Sea sector. In: Problems of the Black Sea. ComSBlack 92, Marine Hydrophysical Institute,
Sevastopol, pp 91–96
Burlakova ZP, Eremeeva LV, Konovalov SK (1997) Particulate organic matter of the Black Sea
euphotic zone: seasonal and long-term variation of spatial distribution and composition. In:
Ozsoy E, Mikaelyan AS (eds) NATO ASI Sciens. Sentivity to change: Black Sea, Baltic Sea
and North Sea. Kluwer Academic Publishers, S2 Enviroment 27, pp 223–238
Burlakova ZP, Eremeeva LV, Krupatkina DK, Chistenko VM (1988) Distribution and elementary
composition of suspended matter in Western and Northwestern Black Sea. In: Formation and
interannual variability of hydrophysical and hydrochemical fields of the Black Sea. (Akad.
Nauk Ukr SSR, Morsk. Gidrofiz. Inst., Sevastopol), pp 162–172 (in Russian)
178
A.S. Kukushkin
Danube discharge impact was more noticeable. In summer, 2005–2015, in both
NWBS areas air temperature increase and the С Chl decrease were observed.
The inter-annual variability patters of the chlorophyll a concentration in the
Romanian and the Bulgarian coastal areas coincided satisfactorily. The correlation
coefficients of the С Chl series in these regions in the spring-autumn period were
rather high (0.7–0.8). The low correlation coefficient, 0.35, was obtained only for
the winter period. The Danube discharge effect on the inter-annual variations of the
chlorophyll a concentrations in the Romanian and the Bulgarian areas was assessed
by the degree of connection between its seasonal concentrations in the Danube area
and in these two ones. The correlation coefficient of С Chl in the Danube and the
Romanian areas in the spring-summer period was equal to 0.7, and in autumn – 0.6.
It testifies to the fact that the phytoplankton bloom and variability in these areas are
affected by the similar factors, one of which is the riverine discharge. In the
Bulgarian area the Danube discharge produces a weaker effect upon the phytoplankton bloom as compared to the Romanian area. This effect is manifested only
in the spring summer period when the transformed river waters flow into the area.
References
Aubrey D, Moncheva S, Demirov E (1996) Envirommental changes in the Western Black Sea
related to anthropogenic and natural conditions. J Mar Syst 7:411–425
Bodeanu N (1992) Algal blooms and development of the main phytoplanktonic species at the
Romanian Black Sea littoral in conditions of intensification of the eutrophication process. In:
Science of the total environment. Elsevier Science Publisher, Amsterdam, pp 31–50
Bodeanu N, Moncheva S, Ruta G, Popa L (1998) Long-term evolution of the algal blooms in
Romanian and Bulgarien Black Sea waters. Cercetari marine – Recherches marines 31:37–55
Bol’shakov VS (1970) Transformation of the river waters in the Black Sea. Naukova Dumka,
Kiev, p 328 (in Russian)
Bologa AS (1977) The phytoplanktonic assimilatory pigments along the Romanian coast of the
Black Sea during 1976. Cercetari marine – Recherches marines 10:95–107
Bologa AS (1978) The monthly dynamics of phytoplanktonic assimilatory pigments from the
sector Conztantza – Agigea of theRomanian Black Sea coast during 1977. Cercetari marine –
Recherches marines (11):77–83
Bologa AS (1985/1986) Planktonic primary productivity of the Black Sea. Thalass Jugosl 21
(22):11–22
Bologa AS (1992) Review of the state of environment and biological changes in Romanian Black
Sea sector. In: Problems of the Black Sea. ComSBlack 92, Marine Hydrophysical Institute,
Sevastopol, pp 91–96
Burlakova ZP, Eremeeva LV, Konovalov SK (1997) Particulate organic matter of the Black Sea
euphotic zone: seasonal and long-term variation of spatial distribution and composition. In:
Ozsoy E, Mikaelyan AS (eds) NATO ASI Sciens. Sentivity to change: Black Sea, Baltic Sea
and North Sea. Kluwer Academic Publishers, S2 Enviroment 27, pp 223–238
Burlakova ZP, Eremeeva LV, Krupatkina DK, Chistenko VM (1988) Distribution and elementary
composition of suspended matter in Western and Northwestern Black Sea. In: Formation and
interannual variability of hydrophysical and hydrochemical fields of the Black Sea. (Akad.
Nauk Ukr SSR, Morsk. Gidrofiz. Inst., Sevastopol), pp 162–172 (in Russian)
178
A.S. Kukushkin