Two new papers resulting from the joint GEOTRACES-PAGES workshop in 2018 are now available in Global Biogeochemical Cycles.
Jesse Farmer et al. compile water column carbon (C), nitrogen (N), and silicon (Si) stable isotopes from GEOTRACES-era data in four key ocean regions to review geochemical proxies of oceanic carbon and nutrient cycling based on the C, N, and Si isotopic composition of marine sediments.
"Assessment of C, N and Si isotopes as tracers of past ocean nutrient and carbon cycling" highlights opportunities for future research using multielement stable isotope proxy applications and emphasizes the importance of such applications to reconstructing past changes in the oceans and climate system.
Tristan Horner et al. study phytoplankton productivity to understand past atmospheric carbon dioxide concentrations and Earth's climate history. Several bioactive trace metals and their isotopes are potential proxies for past phytoplankton productivity, including: iron, zinc, copper, cadmium, molybdenum, barium, nickel, chromium, and silver.
They review the oceanic distributions, driving processes, and depositional archives for these nine metals and their isotopes based on GEOTRACES-era datasets in the paper "Bioactive trace metals and their isotopes as paleoproductivity proxies: An assessment using GEOTRACES-era data".