Influence of land-terminating glacier on primary production in the high Arctic fjord (Blagopoluchiya Bay, Novaya Zemlya archipelago, Kara Sea)

Glaciers retreat linked with rapid Arctic warming changes bioproductivity in the bays and coastal areas of the Arctic Ocean (AO). The impact of different types of glaciers shrinking on water column primary production (IPP) is widely discussed. This work studied the influence of the land-terminating glacier on IPP and chlorophyll a concentration (Chlph) in Blagopoluchiya Bay (Novaya Zemlya archipelago). It is known that meltwater runoff from land-terminating glaciers enriches coastal waters with inorganic suspended matter and nutrients. The aim of the present study was to establish the main environmental factor determining IPP in the bay influenced by the glacier. During summer and autumn, IPP in the bay was low. The medians of IPP were 69 and 26 mgC m ? 2 day- 1, respectively, which was 1.7- and 1.9-fold lower than in open waters of the Kara Sea in the vicinity of the bay. Generally, IPP increased from the inner part, close to the glacier, to the outer part of the bay. In summer, IPP and Chlph depend on both nutrient concentrations in the photosynthetic layer and the parameters of water transparency. On the contrary, in autumn, IPP and Chlph depend only on the optical properties of the subsurface layer. It can be concluded that low IPP in Blagopoluchiya Bay is determined mainly by unfavorable conditions of underwater PAR formed by meltwater discharge from the glacier. Thus, the fast melting of the land-terminating glaciers linked with climate warming can lead to a decrease in the biological productivity of the AO bays.