Marine particle bacteria play an important role in the marine nitrogen cycle

Whether living bacteria from organic matter dissolved in seawater can carry out N2 fixation, and how bacteria have confusing scientists. High levels of oxygen combined with the amount of dissolved organic matter in the seawater column were assumed to prevent anaerobic and energy expenditure N2 fixation.

Already in the 1980s, it was suggested that so-called “marine snow particles” could be suitable for N2 fixation, and that this may have been recently confirmed. Still, it is clear why this N2 fixation bacteria can be found all over the world in the ocean. Furthermore, the global size and distribution of activities was unknown…until now.

A new study shows that researchers from the German Leibniz Centre for Tropical Marine Research, the Institute of Technology in Denmark and the University of Copenhagen use mechanical mathematical models to show that bacteria attached to marine snow particles can broadly correct N2 . The temperatures of the world’s oceans, from tropical to polar, surface to deep by.

This study also shows that the activity of these bacteria accounts for approximately 10% of N2 fixation in the global oceans. This study was just published in the journal Science Advances.

“It’s been almost five years since I started this work while I was a postdoc at the University of Copenhagen,” explains author subhendu Chakraborty. “However, the results are quite breakthroughs, so it was definitely worth the effort. In fact, our study shows that marine N2 fixation is limited to tropical and subtropical surface waters, with cyanobacteria being the only important one. It challenges the longstanding paradigm of being: Diazotrophis.”

The mechanical model also allows researchers to show clear latitudinal distributions of bacteria that anchor N2ON marine snow particles, providing the highest speed of the oxygen minimum zone found in large regions of the world’s oceans. Furthermore, it was shown that particle-associated bacteria can modify N2 over a much wider temperature range than cyanobacteria.

“The size of the N2 fixation and the clear distribution of particle-related activity compared to those known in cyanobacteria is very interesting,” says Lasse Riemann, the research department and co-author. .

“Bacterial activity associated with particles is expected to have an indirect and delayed effect on the marine nitrogen cycle, primarily by immobilizing N2 under the surface layer. These insights is especially important when trying to predict future plankton productivity. The oceans affected by global warming.

Researchers hope that their research will stimulate future work on marine particle microorganism life due to its apparently important role in cycling of many marine nutrients.