近日，高坤山教授等应邀在Frontiers in Marine Science上发表题为“Effects of Ocean Acidification on Marine Photosynthetic Organisms Under the Concurrent Influences of Warming, UV Radiation, and Deoxygenation”的文章，综述了海洋酸化对光合生物效应方面的研究进展，分析了多重环境压力下酸化的影响机制。
Hypothesis 1: Ocean climate changes-induced habitat degradation. Ocean warming, acidification, and deoxygenation associated with increasing atmospheric CO2 rise. A shoaled upper mixed layer due to warming exposes organisms dwelling there to higher levels of solar radiation. The habitable niche degradation hypothesis: phytoplankton abundance and community structure can be altered within the UML under multiple stressors associated with ocean climate changes; and motile organisms dwelling within the UML are stressed due to increased exposure to solar UV radiation and high levels of PAR, which traps more heat; however, the low O2 and pH waters below the UML hamper downward migration.
Hypothesis 2: Ocean acidification (OA) and UV synergistically enhance carbon loss in surface primary producers. This hypothesis is based on the observational data on UV impacts and results that smaller diatoms decrease their growth rate under OA and nutrient-limitation conditions. Diel pH changes in highly productive coastal waters are shown with a sun and a moon symbol to indicate pH rise with increasing photosynthetic C removal during daytime and pH decline with respiratory CO2 release during night. Note that benthic macroalgae contribute greatly to the diel pH fluctuations, and that their growth and photosynthesis are usually stimulated by rising CO2 associated with OA. The symbols “+” and “–” indicate more positive effects due to OA and UV in coastal non-nutrient-limited waters and negative effects due to OA and UV in oligotrophic offshore waters, where shoaling of upper mixed layer owing to warming reduces upward transport of nutrients from deeper layers.
Gao KS*, Beardall J, Hader DP, Hall-Spencer JM, Gao G, Hutchins DA. 2019. Effects of ocean acidification on marine photosynthetic organisms under the concurrent influences of warming, UV radiation and deoxygenation. Frontiers in Marine Science, 6: 322.