Latitudinal gradient in the respiration quotient and the implications for ocean oxygen availability
"Climate-driven depletion of ocean oxygen strongly impacts the global cycles of carbon and nutrients as well as the survival of many animal species. One of the main uncertainties in predicting changes to marine oxygen levels is the regulation of the biological respiration demand associated with the biological pump. Derived from the Redfield ratio, the molar ratio of oxygen to organic carbon consumed during respiration (i.e., the respiration quotient, r −O2:C r−O2:C ) is consistently assumed constant but rarely, if ever, measured. Using a prognostic[...]"
Source: Proceedings of the National Academy of Sciences of the United States of America
Authors: Allison R. Moreno et al.
Ocean acidification could doom key Arctic fish species: study
Ocean acidification combined with warming of the world oceans and loss of oxygen is having a severe impact on key Arctic marine species such as polar cod in the Barents Sea, according to a new study conducted by German scientists.
"The eight-year interdisciplinary study, which began in 2009 and involved more than 250 scientist in the German research network on ocean acidification BIOACID (Biological Impacts of Ocean Acidification), investigated how different marine species respond to ocean acidification – a change in the ocean chemistry that occurs when carbon dioxide (CO2) from the atmosphere dissolves in seawater.
In addition to ocean acidification, the study, Exploring Ocean Change: Biological Impacts of Ocean Acidification, also examined the cascading effect of other stressors such as ocean warming, deoxygenation, overfishing and eutrophication – the increased concentration of nutrients in estuaries and coastal waters that causes harmful algal blooms, ocean dead zones and fish kills. [...]"
Source: The Independent Barents Observer