海洋低氧现象

海洋低氧现象是由于人为活动^[1]而导致的海洋氧含量降低的现象，这是人为排放的二氧化碳^[2]^[3]和富营养化日益严重造成的结果。主要表现为在沿海和河口缺氧区域（或死亡区）的数量不断增加，以及全球海洋中最低氧含量区域的扩大。海洋中氧含量的下降相当迅速，全球低氧海域以每年5.54%的速率增长^[4]，对所有有氧海洋生物以及依赖海洋生物获取营养或生计的人们构成了威胁^[5] ^[6]^[7]^[8]。

一般而言，水中溶解氧浓度小于2mg/L时，就被认为处于低氧状态^[9]。可分为周期性低氧、季节性低氧和持续性低氧^[10]。

当前波罗的海是全球最大的死亡区，20%的海域至少有40年一直处于缺氧状态^[11]，而黑海在150-250米水层处有90%的海域出现低氧现象^[12]。

参看

缺氧事件

参考文献

[1]
Laffoley, D; Baxter, JM. Ocean deoxygenation : everyone’s problem. Switzerland: Gland. 2019: 562 [2020-11-14]. ISBN 978-2-8317-2013-5. （原始内容存档于2021-04-13）.
[2]
Stramma, L; Johnson, GC; Printall, J; Mohrholz, V. Expanding Oxygen-Minimum Zones in the Tropical Oceans. Science. 2008, 320 (5876): 655–658. doi:10.1126/science.1153847.
[3]
Mora, C; et al. Biotic and Human Vulnerability to Projected Changes in Ocean Biogeochemistry over the 21st Century. PLOS Biology. 2013, 11 (10): e1001682. doi:10.1371/journal.pbio.1001682.
[4]
Vaquer-Sunyer, Raquel; Duarte, Carlos M. Thresholds of hypoxia for marine biodiversity. Proceedings of the National Academy of Sciences. 2008-10-07, 105 (40): 15452–15457. doi:10.1073/pnas.0803833105.
[5]
Oceans suffocating as huge dead zones quadruple since 1950, scientists warn. The Guardian. 2018-01-04 [2020-11-14]. （原始内容存档于2021-04-13）.
[6]
Niina Heikkinen, ClimateWire. Ocean's Oxygen Starts Running Low. Scientific American. 2016-05-02 [2020-11-14]. （原始内容存档于2021-02-26）（英语）.
[7]
Long, Matthew C.; Deutsch, Curtis; Ito, Taka. Finding forced trends in oceanic oxygen: TRENDS IN DISSOLVED OXYGEN. Global Biogeochemical Cycles. 2016-02, 30 (2): 381–397. doi:10.1002/2015GB005310.
[8]
Guest post: How global warming is causing ocean oxygen levels to fall. Carbon Brief. 2018-06-15 [2020-11-14]. （原始内容存档于2021-02-04）（英语）.
[9]
Gray, Js; Wu, Rs; Or, Yy. Effects of hypoxia and organic enrichment on the coastal marine environment. Marine Ecology Progress Series. 2002, 238: 249–279. doi:10.3354/meps238249.
[10]
Diaz, R. J.; Rosenberg, R. Spreading Dead Zones and Consequences for Marine Ecosystems. Science. 2008-08-15, 321 (5891): 926–929. doi:10.1126/science.1156401.
[11]
Conley, Daniel J.; Humborg, Christoph; Rahm, Lars; Savchuk, Oleg P.; Wulff, Fredrik. Hypoxia in the Baltic Sea and Basin-Scale Changes in Phosphorus Biogeochemistry. Environmental Science & Technology. 2002-12, 36 (24): 5315–5320. doi:10.1021/es025763w.
[12]
Diaz, Robert J. Overview of Hypoxia around the World. Journal of Environmental Quality. 2001-03, 30 (2): 275–281. doi:10.2134/jeq2001.302275x.

[IUCN2019-1] [1]
Laffoley, D; Baxter, JM. Ocean deoxygenation : everyone’s problem. Switzerland: Gland. 2019: 562 [2020-11-14]. ISBN 978-2-8317-2013-5. （原始内容存档于2021-04-13）.

[Stramma-2] [2]
Stramma, L; Johnson, GC; Printall, J; Mohrholz, V. Expanding Oxygen-Minimum Zones in the Tropical Oceans. Science. 2008, 320 (5876): 655–658. doi:10.1126/science.1153847.

[Mora-3] [3]
Mora, C; et al. Biotic and Human Vulnerability to Projected Changes in Ocean Biogeochemistry over the 21st Century. PLOS Biology. 2013, 11 (10): e1001682. doi:10.1371/journal.pbio.1001682.

[4] [4]
Vaquer-Sunyer, Raquel; Duarte, Carlos M. Thresholds of hypoxia for marine biodiversity. Proceedings of the National Academy of Sciences. 2008-10-07, 105 (40): 15452–15457. doi:10.1073/pnas.0803833105.

[5] [5]
Oceans suffocating as huge dead zones quadruple since 1950, scientists warn. The Guardian. 2018-01-04 [2020-11-14]. （原始内容存档于2021-04-13）.

[6] [6]
Niina Heikkinen, ClimateWire. Ocean's Oxygen Starts Running Low. Scientific American. 2016-05-02 [2020-11-14]. （原始内容存档于2021-02-26）（英语）.

[7] [7]
Long, Matthew C.; Deutsch, Curtis; Ito, Taka. Finding forced trends in oceanic oxygen: TRENDS IN DISSOLVED OXYGEN. Global Biogeochemical Cycles. 2016-02, 30 (2): 381–397. doi:10.1002/2015GB005310.

[8] [8]
Guest post: How global warming is causing ocean oxygen levels to fall. Carbon Brief. 2018-06-15 [2020-11-14]. （原始内容存档于2021-02-04）（英语）.

[9] [9]
Gray, Js; Wu, Rs; Or, Yy. Effects of hypoxia and organic enrichment on the coastal marine environment. Marine Ecology Progress Series. 2002, 238: 249–279. doi:10.3354/meps238249.

[10] [10]
Diaz, R. J.; Rosenberg, R. Spreading Dead Zones and Consequences for Marine Ecosystems. Science. 2008-08-15, 321 (5891): 926–929. doi:10.1126/science.1156401.

[11] [11]
Conley, Daniel J.; Humborg, Christoph; Rahm, Lars; Savchuk, Oleg P.; Wulff, Fredrik. Hypoxia in the Baltic Sea and Basin-Scale Changes in Phosphorus Biogeochemistry. Environmental Science & Technology. 2002-12, 36 (24): 5315–5320. doi:10.1021/es025763w.

[12] [12]
Diaz, Robert J. Overview of Hypoxia around the World. Journal of Environmental Quality. 2001-03, 30 (2): 275–281. doi:10.2134/jeq2001.302275x.

[1]

[2]

[3]

[4]

[5]

[6]

[7]

[8]

[9]

[10]

[11]

[12]