Relationship of the processes of aerobic oxidation and anaerobic destruction of organic matter in the bottom sediments of coastal waters of Crimea (Black Sea)
The relationship between water masses and bottom sediments is obvious. This primarily refers to the formation of oxygen regime and self-purification of water bodies. Stoichiometric ratios allow assessing certain parameters of energy metabolism associated with oxygen consumption. The aim of this wor...
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| Format: | Article |
| Language: | English |
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A. O. Kovalevsky Institute of Biology of the Southern Seas of RAS
2023-09-01
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| Series: | Морской биологический журнал |
| Subjects: | |
| Online Access: | https://marine-biology.ru/mbj/article/view/400 |
| _version_ | 1797244342164783104 |
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| author | V. P. Chekalov |
| author_facet | V. P. Chekalov |
| author_sort | V. P. Chekalov |
| collection | DOAJ |
| description |
The relationship between water masses and bottom sediments is obvious. This primarily refers to the formation of oxygen regime and self-purification of water bodies. Stoichiometric ratios allow assessing certain parameters of energy metabolism associated with oxygen consumption. The aim of this work is to determine the possible contribution of aerobic and anaerobic processes to the destruction of organic matter in bottom sediments of various areas of the Crimean coast by interpreting the data on oxygen consumption. The total oxygen consumption rate was measured using a respirometry camera hermetically connected to an HQ40D oxygen sensor with LDO oximeter. To suppress bacterial activity and reveal the rate of oxidation of reduced anaerobiotic products, the antibiotic streptomycin was used. Vertical sounding of the bottom sediment strata in the Belbek River paleochannel showed an increase with depth of oxidative potential and a subsurface peak of anaerobic activity. Due to the limited diffusion of oxygen, the rate of hydrogen sulfide oxidation in the surface layer was comparable to the rate of its formation in the underlying sediment layer. A higher level of aerobic oxygen consumption and content of reduced compounds was observed in the bottom sediments of the Chernaya River paleochannel in contrast to its slopes. Increased concentration of hydrogen sulfide is due to the higher rate of its formation at relatively low rates of oxidation. In the Sevastopol Bay, the experimentally measured oxygen consumption by a unit of the bottom surface in the 0.6-cm sediment layer averaged 2.18 μg·cm−2·h−1. In the Kruglaya Bay, certain differences in the dynamics of reduced compounds (H2S) were registered between the oxidized background areas and the zones of reduced bottom sediments (sulfurettes). In sulfurettes, the calculated values for concentration, oxidation rate, and formation of hydrogen sulfide were higher by 32, 29, and 57%, respectively. The maximum rate of organic matter decomposition, up to 4.05 μg·cm−3·h−1, was recorded in the Sevastopol Bay and the adjacent water areas, with the anaerobic component accounting for a larger share. The share turned out to be quite high in the Kruglaya Bay as well, but there, aerobic destruction prevailed. This is due to differences in both the targeted use of the bays and the granulometric composition of bottom sediments. In sulfurette sediments, against the backdrop of the rate of oxidation of organic substances equal to that of the background area, anaerobic utilization occurred more than 2 times more intensive. Its absolute value corresponded to the level characteristic of the open-sea coastal areas, in particular, the Belbek River paleochannel.
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| first_indexed | 2024-03-11T18:15:07Z |
| format | Article |
| id | doaj.art-666aff70d4e649558c0bb1b28d3b1321 |
| institution | Directory Open Access Journal |
| issn | 2499-9768 2499-9776 |
| language | English |
| last_indexed | 2024-04-24T19:09:29Z |
| publishDate | 2023-09-01 |
| publisher | A. O. Kovalevsky Institute of Biology of the Southern Seas of RAS |
| record_format | Article |
| series | Морской биологический журнал |
| spelling | doaj.art-666aff70d4e649558c0bb1b28d3b13212024-03-26T13:35:18ZengA. O. Kovalevsky Institute of Biology of the Southern Seas of RASМорской биологический журнал2499-97682499-97762023-09-018310.21072/mbj.2023.08.3.06Relationship of the processes of aerobic oxidation and anaerobic destruction of organic matter in the bottom sediments of coastal waters of Crimea (Black Sea)V. P. Chekalov0A. O. Kovalevsky Institute of Biology of the Southern Seas of RAS, Sevastopol, Russian Federation The relationship between water masses and bottom sediments is obvious. This primarily refers to the formation of oxygen regime and self-purification of water bodies. Stoichiometric ratios allow assessing certain parameters of energy metabolism associated with oxygen consumption. The aim of this work is to determine the possible contribution of aerobic and anaerobic processes to the destruction of organic matter in bottom sediments of various areas of the Crimean coast by interpreting the data on oxygen consumption. The total oxygen consumption rate was measured using a respirometry camera hermetically connected to an HQ40D oxygen sensor with LDO oximeter. To suppress bacterial activity and reveal the rate of oxidation of reduced anaerobiotic products, the antibiotic streptomycin was used. Vertical sounding of the bottom sediment strata in the Belbek River paleochannel showed an increase with depth of oxidative potential and a subsurface peak of anaerobic activity. Due to the limited diffusion of oxygen, the rate of hydrogen sulfide oxidation in the surface layer was comparable to the rate of its formation in the underlying sediment layer. A higher level of aerobic oxygen consumption and content of reduced compounds was observed in the bottom sediments of the Chernaya River paleochannel in contrast to its slopes. Increased concentration of hydrogen sulfide is due to the higher rate of its formation at relatively low rates of oxidation. In the Sevastopol Bay, the experimentally measured oxygen consumption by a unit of the bottom surface in the 0.6-cm sediment layer averaged 2.18 μg·cm−2·h−1. In the Kruglaya Bay, certain differences in the dynamics of reduced compounds (H2S) were registered between the oxidized background areas and the zones of reduced bottom sediments (sulfurettes). In sulfurettes, the calculated values for concentration, oxidation rate, and formation of hydrogen sulfide were higher by 32, 29, and 57%, respectively. The maximum rate of organic matter decomposition, up to 4.05 μg·cm−3·h−1, was recorded in the Sevastopol Bay and the adjacent water areas, with the anaerobic component accounting for a larger share. The share turned out to be quite high in the Kruglaya Bay as well, but there, aerobic destruction prevailed. This is due to differences in both the targeted use of the bays and the granulometric composition of bottom sediments. In sulfurette sediments, against the backdrop of the rate of oxidation of organic substances equal to that of the background area, anaerobic utilization occurred more than 2 times more intensive. Its absolute value corresponded to the level characteristic of the open-sea coastal areas, in particular, the Belbek River paleochannel. https://marine-biology.ru/mbj/article/view/400bottom sedimentsoxygen consumptiondestruction of organic matterBlack Sea |
| spellingShingle | V. P. Chekalov Relationship of the processes of aerobic oxidation and anaerobic destruction of organic matter in the bottom sediments of coastal waters of Crimea (Black Sea) Морской биологический журнал bottom sediments oxygen consumption destruction of organic matter Black Sea |
| title | Relationship of the processes of aerobic oxidation and anaerobic destruction of organic matter in the bottom sediments of coastal waters of Crimea (Black Sea) |
| title_full | Relationship of the processes of aerobic oxidation and anaerobic destruction of organic matter in the bottom sediments of coastal waters of Crimea (Black Sea) |
| title_fullStr | Relationship of the processes of aerobic oxidation and anaerobic destruction of organic matter in the bottom sediments of coastal waters of Crimea (Black Sea) |
| title_full_unstemmed | Relationship of the processes of aerobic oxidation and anaerobic destruction of organic matter in the bottom sediments of coastal waters of Crimea (Black Sea) |
| title_short | Relationship of the processes of aerobic oxidation and anaerobic destruction of organic matter in the bottom sediments of coastal waters of Crimea (Black Sea) |
| title_sort | relationship of the processes of aerobic oxidation and anaerobic destruction of organic matter in the bottom sediments of coastal waters of crimea black sea |
| topic | bottom sediments oxygen consumption destruction of organic matter Black Sea |
| url | https://marine-biology.ru/mbj/article/view/400 |
| work_keys_str_mv | AT vpchekalov relationshipoftheprocessesofaerobicoxidationandanaerobicdestructionoforganicmatterinthebottomsedimentsofcoastalwatersofcrimeablacksea |