Provenance analysis of organic carbon preserved in coastal marine sediments by DNA biomarkers

Abstract

As a tool for tracing organic carbon derived from marine macrophytes, a method for quantifying DNA biomarkers of temperate seagrasses (Zostera spp.) in coastal sediments by the real-time PCR has been developed. Using this method, seagrass DNA was successfully detected from some seagrass bed sediment cores, and the results obtained were generally consistent with organic carbon and carbon stable isotope distributions through the cores. The seagrass DNA has been detected even from deep sediment samples dated >2,000 yr b.p. by the conventional C-14 method. Spatial distribution of seagrass DNA biomarkers over offshore surface sediments indicated that there are specific sink" regions of seagrass-derived organic carbon nearby source areas. A quantitative relationship between the amount of seagrass DNA and the concentration of seagrass-derived organic carbon in the sediment is being explored now."