Latitudinal variations of zooplankton community structure and productivity in the Barents sea (summer 2013)

• Published in: GEOGRAPHY, ENVIRONMENT, SUSTAINABILITY
• Main Authors: V. Dvoretsky G., A. Dvoretsky G., В. Дворецкий Г., А. Дворецкий Г.
• Other Authors: Russian Science Foundation, project № 17-14-01268, Российский научный фонд, проект № 17-14-01268
• Format: Article in Journal/Newspaper
• Language: Russian
• Published: Государственный научный центр Российской Федерации Арктический и антарктический научно-исследовательский институт 2018
• Subjects: Barents sea; biomass; stock; zooplankton; Баренцево море; биомасса; запас; зоопланктон; Arctic; Barents Sea; Murmansk; Calanus finmarchicus; Calanus glacialis; Phytoplankton; Polar Biology; Polar Research; Reports on polar research; Zooplankton
• Online Access: https://www.aaresearch.science/jour/article/view/32; https://doi.org/10.30758/0555-2648-2018-64-3-294-310

The Barents Sea is regarded as one of the world’s most unique regions with its high summer productivity. However, there were a few studies dealing with estimation of daily secondary production in the Barents Sea. The aim of the present study was to conduct an investigation of the pelagic mesozooplankton assemblage in the Barents Sea, to calculate daily production levels of mesozooplankton and to analyze the relationship between the community structure and environmental drivers.Structure of zooplankton communities was investigated within the main water masses of the Barents Sea in the summer 2013 (June–July). Calanus finmarchicus presented as copepodites IV–V dominated in terms of the total zooplankton abundance and biomass in Murmansk Coastal Water and Atlantic Water. Spring phase of zooplankton succession cycle was found in Arctic Water where Copepoda nauplii were the most abundant and Calanus glacialis dominated by zooplankton biomass. Zooplankton of the Barents Sea Water had features of spring and summer phases of zooplankton succession cycle. Spatial variations in the zooplankton distribution were associated with hydrological conditions and phytoplankton density. Maximum of the mean zooplankton biomass was registered in Atlantic Water (30,7 mg dry mass/m3) while the minimum was found in Barents Sea Water (5,4 mg dry mass/m3). Calculated daily production of zooplankton ranged from 0,01 to 1,57 mg dry mass/m3 per day. Total zooplankton stock for the study area of 281 000 km2 was estimated to be > 740 000 t of dry mass. The obtained values of zooplankton biomass and stock were considerably lower than in previous years, which are probably connected with higher predator pressure — grazing of zooplankton by capelin and other predators as well as with possible climatic influence. Исследована структура зоопланктона в пределах основных водных масс Баренцева моря. В мурманской прибрежной и атлантической водной массах по численности и биомассе зоопланктона доминировал Calanus finmarchicus. В арктической водной массе преобладали науплии копепод, основу биомассы составлял Calanus glacialis. Пространственные вариации распределения зоопланктона были связаны с гидрологическими факторами и концентрацией фитопланктона. Наибольшая средняя биомасса отмечена в атлантических водах, наименьшая — в баренцевоморских. Общий запас зоопланктона для исследованной акватории площадью 281 тыс. км2 составил более 740 тыс. т сухой массы. Биомасса, продукция и запас зоопланктона были существенно ниже, чем в предшествующие годы, что, скорее всего, связано с более высоким прессом мойвы и других хищников, также возможным влиянием климатических факторов.