OA Week 2021, Plenary Session 5 Attribution & Blue Carbon
Dr. Rushingisha George, Researcher, Tanzania Fisheries Research Institute (TAFIRI), Tanzania
Description:
As concentration of anthropogenic CO2 continues to increase in the atmosphere, both ocean warming and acidification will continue to increase globally. This can have both negative and positive impacts on the health and function of seagrasses, which are key primary producers and ecosystem engineers in the coastal zone. The key physiological processes (photosynthesis, calcification and respiration) of these plants operate over a wide range of climatic factors (temperature, CO2, dissolved oxygen etc.) and their response can serve to mitigate the impacts of ocean acidification on short-time scales. This talk will focus on the responses of seagrass physiological processes to elevated climatic factors (under both current and future conditions) in the water column, and how these responses affect the pH of the water column as well as on the effect of the tidal variability on pH of seagrass meadows and adjacent coastal habitats. Research findings show that seagrass physiological processes respond differently to elevated climatic factors and their interaction govern the pH of the system. The effect of physiological processes on pH of seagrass meadows of intertidal waters depend on the water level and percentage cover, and is highest during low spring tides. Photosynthetic uptake of dissolved inorganic carbon (DIC) can raise the mean pH of seagrass meadows, and adjacent mangrove and coral reef habitats to 5% above that of adjacent open ocean during daytime at high tide. These findings show that healthy seagrass meadows offer a huge potential to mitigate the impacts of ocean acidification, as their photosynthetic uptake of DIC have been shown raise the mean pH of seagrass meadows, and adjacent mangrove and coral reef habitats to 5% above that of adjacent open ocean during daytime at high tide. Therefore, reducing anthropogenic stressors such as eutrophication by land-based pollution sources, among others, will make seagrass meadows healthy and resilient to elevated water temperatures while mitigating the impacts of ocean acidification on temporal scales.”
Ocean Acidification Week 2021 was sponsored by the following organizations:
(1) GOA-ON, the Global Ocean Acidification Observing Network,
(2) NOAA, the United States National Oceanic & Atmospheric Administration,
(3) IAEA OA-ICC, the International Atomic Energy Agency – Ocean Acidification International Coordination Centre, and
(4) IOC-UNESCO – the Intergovernmental Oceanographic Commission of the United Nations Educational, Scientific and Cultural Organization
For more information, please visit www.goa-on.org
GOA-ON, YouTube, 24 September 2021. Text and video.
