Premium
Terrestrial Biomolecular Burial Efficiencies on Continental Margins
Author(s) -
Hou Pengfei,
Yu Meng,
Zhao Meixun,
Montluçon Daniel B.,
Su Chenglong,
Eglinton Timothy I.
Publication year - 2020
Publication title -
journal of geophysical research: biogeosciences
Language(s) - English
Resource type - Journals
eISSN - 2169-8961
pISSN - 2169-8953
DOI - 10.1029/2019jg005520
Subject(s) - terrestrial plant , environmental science , oceanography , atmosphere (unit) , fluvial , seawater , environmental chemistry , earth science , geology , ecology , chemistry , paleontology , biology , geography , structural basin , meteorology
The fate of terrestrial organic carbon (OC terr ) exported from large rivers in marginal seas is an integral component of land‐ocean‐atmosphere carbon dynamics and influences on atmospheric CO 2 concentrations on millennial and longer timescales. In this study, we employ a novel approach to constrain burial efficiencies for source‐specific terrestrial biomolecules (long‐chain n ‐alkanes and n ‐fatty acids) in two river‐marginal sea systems. We find for the Pearl River‐South China Sea system that 34 ± 19% and 11 ± 4% of n ‐alkanes and n ‐fatty acids, respectively, are preserved across the transport pathway from the river mouth to inner shelf. In contrast, terrestrial biomolecular burial efficiencies were markedly higher (64 ± 17% and 84 ± 30% of n ‐alkanes and n ‐fatty acids, respectively) in the Yellow River‐Bohai Sea/Yellow Sea system. These findings reveal markedly different fates of OC terr in these two fluvial‐marine systems, as well as sharp contrasts in OC terr reactivity within each system.