A study led by Oldenburg researchers finds new explanation for the accumulation of organic compounds in oxygen-depleted marine areas. The effect could negatively feedback on the climate on geological time scales.
The Black Sea is an unusual body of water: below a depth of 150 metres the dissolved oxygen concentration sinks to around zero, meaning that higher life forms such as plants and animals cannot exist in these areas. At the same time, this semi-enclosed sea stores comparatively large amounts of organic carbon. A team of researchers led by Dr Gonzalo V. Gomez-Saez and Dr Jutta Niggemann from the University of Oldenburg's Institute for Chemistry and Biology of the Marine Environment (ICBM) has now presented a new hypothesis as to why organic compounds accumulate in the depths of the Black Sea – and other oxygen-depleted waters in the scientific journal Science Advances.
The researchers posit that reactions with hydrogen sulfide play an important role in stabilizing carbon compounds. "This mechanism apparently contributes to the fact that there is more than twice as much organic carbon in the waters of the Black Sea as in oxygen-rich marine areas," says Niggemann. "This provides a negative feedback in the climate system that could counteract global warming over geological periods."
Read more at University of Oldenburg
Image: Die Expedition MSM15-1 des Forschungsschiffs Maria S. Merian, auf der Oldenburger Forschende die Daten für die vorliegende Studie sammelten, begann in Istanbul. (Photo Credit: Felix Janssen)