TY - JOUR T1 - Erosion of modern terrestrial organic matter as a major component of sediments in fjords JF - Geophysical Research Letters Y1 - 2017 A1 - Cui, Xingqian A1 - Bianchi, Thomas S. A1 - Savage, Candida AB - Fjords have recently been recognized as “hot spots” of carbon burial. In this study, we investigated organic carbon (OC) and biomarker radiocarbon values in fjord sediments from New Zealand. Our results showed that OC was mostly modern with the most aged OC in middle reaches of fjords, likely related to hydrodynamic sorting and inputs along adjacent slopes. Radiocarbon ages of sedimentary OC increased from north-to-south, consistent with the Fiordland regional gradients of lower fjord slopes and less rainfall. Our biomarker results suggested that lignin and long-chain fatty acids were preferentially linked with fresh terrestrial debris and degraded soil, respectively, likely due to their chemical and physical properties. Finally, we propose that fjords are a significant sink of modern OC, in contrast to large lowland coastal systems as a major sink of preaged OC. Overall, this study indicated that radiocarbon techniques are critical in investigating carbon dynamics in coastal systems. VL - 442824441945245112168105110293225215662639493436151675187268234320723424507431438414191121427211539259 UR - http://doi.wiley.com/10.1002/2016GL072260http://onlinelibrary.wiley.com/wol1/doi/10.1002/2016GL072260/fullpdfhttps://api.wiley.com/onlinelibrary/tdm/v1/articles/10.1002%2F2016GL072260 IS - 345355903755111181-21212316171193141-2182341 ER -