δ13C and δ15N Values of Sediment-trap Particles in the Japan and Yamato Basins and Comparison with the Core-top Values in the East/Japan Sea
- 81 Downloads
Investigation of sediment-trap deployments in the East/Japan Sea (EJS) showed that distinct seasonal variations in particulate organic carbon (POC) fluxes of intermediate-water sediment-traps clearly corresponded to changes in chlorophyll a concentrations estimated from SeaWiFS data. The prominent high POC flux periods (e.g., March) were strongly correlated with the enhanced surface-water phytoplankton blooms. Deep-water sedimenttraps exhibited similar variation patterns to intermediate-water sediment-traps. However, their total flux and POC flux were higher than those of intermediate-water sediment-traps during some months (e.g., April and May), indicating the lateral delivery of some particles to the deep-water sediment-traps. Distinct seasonal δ13C and δ15N variations in settling particles of the intermediate-water sediment-traps were observed, strongly supporting the notion of seasonal primary production. Seasonal variations in δ13C and δ15N values from the deep-water sediment-traps were similar to those of the intermediate-water sediment-traps. However, the difference in δ13C and δ15N values between the intermediate-water and the deepwater sediment-traps may be attributed to degradation of organic matter as it sank through the water column. Comparison of fluxweighted δ13C and δ15N mean values between the deep-water sediment-traps and the core-top sediments showed that strong selective loss of organic matter components (lipids) depleted in 13C and 15N occurred during sediment burial. Nonetheless, the results of our study indicate that particles in the deep-water sediment-trap deposited as surface sediments on the seafloor preserve the record of surface-water conditions, highlighting the usefulness of sedimentary δ13C and δ15N values as a paleoceanographic application in the EJS.
Keywordssediment-trap carbon isotope nitrogen isotope surface-water production seasonality Japan Basin Yamato Basin
Unable to display preview. Download preview PDF.
- Altabet MA (1996) Nitrogen and carbon isotope tracers of the source and transformation of particles in the deep sea. In: Ittekkot V (ed) Particle flux in the ocean. John Wiley & Sons Ltd., pp 155–184Google Scholar
- de Lange GJ, van Os B, Pruysers PA, Middelburg JJ, Castradori D, van Santvoort P, Muller PJ, Eggenkamp H, Prahl FG (1994) Possible early diagenetic alteration of palaeo proxies. In: Zahn R, Pedersen TF, Kaminski MA, Labeyrie L (eds) Carbon cycling in the glacial ocean: constraints on the ocean’s role in global change. Springer, Berlin, pp 225–258CrossRefGoogle Scholar
- Lourey MJ, Trull JT, Sigman DM (2003) Sensitivity of δ15N of nitrate, surface suspended and deep sinking particulate nitrogen to seasonal nitrate depletion in the Southern Ocean. Global Biogeochem Cy 17. doi:10.1029/2002GB001973Google Scholar
- Moon CH, Yang SR, Yang HS, Cho HJ, Lee SY, Kim SY (1998) Regeneration process of nutrients in the polar front area of the East Sea: Chlorophyll a distribution, new production and the vertical diffusion of nitrate. Bull Korean Fish Soc 31:259–266 (in Korean)Google Scholar
- Park JS, Kang CK, An KH (1991) Community structure and spatial distribution of phytoplankton in the polar front region off the east coast of Korea in summer. Bull Korean Fish Soc 24:237–247 (in Korean)Google Scholar
- Park KA, Chung JY, Kim K (2004) Sea surface temperature fronts in the East (Japan) Sea and temporal variations. Geophys Res Lett 31:L07304. doi:10.1029/2004GL019424Google Scholar