The rates of organic matter destruction in the central part of the Arctic Basin

• Published in: Oceanology (Washington. 1965) Vol. 51; no. 5; pp. 775 - 784
• Main Authors: Agatova, A. I., Lapina, N. M., Torgunova, N. I.
• Format: Journal Article
• Language: English
• Published: Dordrecht SP MAIK Nauka/Interperiodica 01-10-2011; Springer Nature B.V
• Subjects: Biochemistry; Biodegradation; Chemical oceanography; Deep water; Earth and Environmental Science; Earth Sciences; Enzymes; Marine; Marine Chemistry; Microorganisms; Oceanography; Organic carbon; Organic matter; Arctic Ocean; PN, Arctic Basin; Arctic Ocean; Photic Layer; Azocasein; Electron Transport System; Arctic Basin
• ISSN: 0001-4370; 1531-8508
• DOI: 10.1134/S0001437011050018

The intensity of the processes of organic matter (OM) destruction in the deep-water part of the Arctic Basin is considered in terms of the activities of hydrolytic enzymes (alkaline phosphatase and proteases) and of redox enzymes of the electron transport system (ETS). High concentrations of mineral phosphorus are shown to cause low phosphatase activity (0.000–0.005 μM P/l h). The average time of the phosphate recycling amounted to about 240 h. The ranges of the total and specific activity of protease are 0.000–0.192 mg of azocasein/(l h) and 0.00–3.57 mg of azocasein/h mg of protein, respectively. It is found that the microplankton production of exo- and endopeptidase in the Arctic Basin is controlled by the concentration of nitrates in the water. The values of the total and the specific activities of the ETS enzymes vary within 0.27–8.96 μl O
2
/(l h) and 8.4–583 μl O
2
/mg of protein h, respectively. It is shown that the maximum values of the total activities of the hydrolytic and redox enzymes are characteristic for the photic layer. The vertical fluxes of organic carbon from the photic layer, being calculated by the activity of the ETS enzymes, amounted to 220–600 g of C
org
/year m
2
. The presence of ice intensifies the redox processes by factors of 2–15.