Calcium and iron promote reversible self‑assembly of dissolved organic matter into particles

Open access: https://link.springer.com/article/10.1007/s10533-025-01284-x

Dissolved organic matter released by phytoplankton (i.e., acidic polysaccharides) or of terrestrial origin (humic and fulvic acids) can coagulate to form particles by the intervention of cations such as calcium and iron. These particles can be stored for a long time in the sediments affecting the global carbon cycle or be directly consumed by protozoa and zooplankton, forming the particulate loop.

We dedicated this paper to the memory of our mentor, colleague, and friend, Jonathan Cole, who always had time to listen and inspire us.