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Материал Light absorption and maximum quantum yield of photosynthesis during autumn phytoplankton bloom in the western Black Sea(2008) Churilova, T.; Finenko, Z.; Tugrul, S.In the frame of GEF/UNDP Black Sea Ecosystem Recovery Project the effect of nutrient availability on phytoplankton light absorption and maximum quantum yield of carbon fixation (max) has been investigated. It has been found out that chlorophyll a concentration (Chl a) varied from 0.3 to 10 mg m-3 increasing from deep-water region to shelf waters. At the shallow stations, where upper mixed layer spread deeper the bottom of euphotic zone, the homogenous pigment distribution was observed. In the deep-water region the Chl a profiles showed the presence of a deep Chl a maximum (DCM) below a seasonal density cline. The functional characteristics of phytoplankton showed depth-dependent variation. The phytoplankton from DCM was characterized 20 % lower values of spectral averaged Chl-a – specific light absorption (0.016±0.0025 m2 (mgChl)-1) and more than in two times higher values of max (0.070±0.012 molC (mol quanta)-1) compared with the surface phytoplankton (0.021±0.0035 m2 (mgChl)-1) and max (0.030±0.0078 molC (mol quanta)-1). From offshore to shallow stations the increasing of surface Chl a concentration was accompanied with slight decrease of (on ~20 %) and significant increase of max up to its theoretical limit - 0.1 molC (mol quanta)-1, which were caused by an increase in nutrient supply across the shelf.Материал Photosynthetic characteristics of phytoplankton in the western Black Sea during the autumn bloom(2008) Finenko, Z.; Churilova, T.; Parkhomenko, A.; Tugrul, S.In the autumn of 2005 photosynthetic characteristics of phytoplankton were studied along transects from a coast to deep-waters in the western and southern Black Sea. Efficiency of photosynthesis (αB) varied from 0.012 to 0.068 mg C (mg Chl)-1h-1(μE m-2 s-1)-1. Light – saturated rate of chlorophyll a-normalized photosynthesis (P) ranged from 5 mg C (mg Chl)-1 h-1 in the deep-waters to 12 mg C (mg Chl)-1 h-1 in the shelf waters. In the shelf area P and αB varied by a factor of 3. Variability of these parameters was as lower as that of the chlorophyll concentration. The mean αB and P values at the shelf were higher than those of the deep-water region. The phodoadaptive strategy of phytoplankton was characterized by increasing of αB at lower light levels. During the warm period of year nutrient effect on photosynthetic parameters was critical in their variability. The total integrated primary production (PP) varied from 0.34 to 2.45 gC m-2 day-1. Mean PP values were 1.7 and 0.5 gC m-2 day-1 in the shelf and deep-waters respectively. Strong correlations between PP, P, αB and surface chlorophyll concentration have been obtained.Материал ОТНОШЕНИЕ ОРГАНИЧЕСКОГО УГЛЕРОДА К ХЛОРОФИЛЛУ “А“ В ФИТОПЛАНКТОНЕ ПОВЕРХНОСТНЫХ ВОД ЗАПАДНОЙ ЧАСТИ ЧЕРНОГО МОРЯ В ПЕРИОД ОСЕННЕГО “ЦВЕТЕНИЯ“(Севастополь: ЭКОСИ-Гидрофизика, 2006) Стельмах, Л. В.; Бабич, И. И.; Тугрул, С.В сентябре – октябре 2005 г. в прибрежных водах Болгарии, Турции и на северо-западном шельфе у побережья Крыма отмечено интенсивное развитие диатомовых водорослей, что сопровождалось повышением концентрации хлорофилла “а“ до 2 – 5 мг/м3, тогда как в глубоководной области его содержание не превышало 0,54 мг/м3. Показано, что отношение органического углерода к хлорофиллу “а“ в нано- и микрофитопланктоне исследованных вод изменялось от 30 до 293. Установлено, что в данный период основным фактором, регулирующим пространственную изменчивость величины С/Хл“а“, является концентрация аммонийного азота.