DiscussionThe phytolith carbon sequestration concept: Fact or fiction? A comment on “Occurrence, turnover and carbon sequestration potential of phytoliths in terrestrial ecosystems by Song et al. doi: 10.1016/j.earscirev.2016.04.007”

In their review, Song et al. (2016) overstate the validity of the atmospheric carbon sequestration potential of phytoliths as they misrepresent recent literature on the topic and omit any evidence that calls into question this concept. Here, we evaluate and present the full range of the misrepresented and omitted literature, and question the representativeness of their original assumptions. We also address Song et al.'s concerns regarding isotopic fractionation and/or the negative effects of over-rigorous oxidation on the isotopic analysis of phytoliths. Finally, we call for further data acquisition to properly quantify all the fluxes involved in the phytolith carbon cycle.