Red coralline algae assessed as marine pH proxies using 11B MAS NMR


Cusack M, Kamenos NA, Rollion-Bard C & Tricot G (2015) Red coralline algae assessed as marine pH proxies using 11B MAS NMR. Scientific Reports, 5, Art. No.: 8175.

Reconstructing pH from biogenic carbonates using boron isotopic compositions relies on the assumption that only borate, and no boric acid, is present. Red coralline algae are frequently used in palaeoenvironmental reconstruction due to their widespread distribution and regular banding frequency. Prior to undertaking pH reconstructions using red coralline algae we tested the boron composition of the red coralline alga Lithothamnion glaciale using high field NMR. In bulk analysed samples, thirty percent of boron was present as boric acid. We suggest that prior to reconstructing pH using coralline algae 1) species-specific boron compositions and 2) within-skeleton special distributions of boron are determined for multiple species. This will enable site selective boron analyses to be conducted validating coralline algae as palaeo-pH proxies based on boron isotopic compositions.

biogeochemistry; climate sciences

Scientific Reports: Volume 5

Publication date28/02/2015
Publication date online02/02/2015
Date accepted by journal12/01/2015
PublisherSpringer Nature