The ratio of atmosphere-derived Be to continent-derived Be in marine sediments has been used to probe the long-term relationship between continental denudation and climate. However, its application is complicated by uncertainty in Be transfer through the land-ocean interface. The riverine dissolved load alone is insufficient to close the marine Be budget, largely due to substantial removal of riverine Be to continental margin sediments. We focus on the ultimate fate of this latter Be. We present sediment pore-water Be profiles from diverse continental margin environments to quantify the diagenetic Be release to the ocean. Our results suggest that pore-water Be cycling is mainly controlled by particulate supply and Mn-Fe cycling, leading to higher benthic fluxes on shelves. Benthic fluxes may help close the Be budget and are at least comparable to, or higher (~2-fold) than, the riverine dissolved input. These observations demand a revised model framework, which considers the potentially dominant benthic source, to robustly interpret marine Be isotopic records.
Download full-text PDF |
Source |
---|---|
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC10246903 | PMC |
http://dx.doi.org/10.1126/sciadv.adg3702 | DOI Listing |
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!