Articles | Volume 20, issue 17
Research article
13 Sep 2023
Research article |  | 13 Sep 2023

Multiple nitrogen sources for primary production inferred from δ13C and δ15N in the southern Sea of Japan

Taketoshi Kodama, Atsushi Nishimoto, Ken-ichi Nakamura, Misato Nakae, Naoki Iguchi, Yosuke Igeta, and Yoichi Kogure

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Cited articles

Antonio, E. S., Kasai, A., Ueno, M., Ishihi, Y., Yokoyama, H., and Yamashita, Y.: Spatial-temporal feeding dynamics of benthic communities in an estuary-marine gradient, Estuar. Coast. Shelf S., 112, 86–97,, 2012. 
Buchanan, P. J., Matear, R. J., Chase, Z., Phipps, S. J., and Bindoff, N. L.: Ocean carbon and nitrogen isotopes in CSIRO Mk3L-COAL version 1.0: a tool for palaeoceanographic research, Geosci. Model Dev., 12, 1491–1523,, 2019. 
Duan, S. W., Xu, F., and Wang, L. J.: Long-term changes in nutrient concentrations of the Changjiang River and principal tributaries, Biogeochemistry, 85, 215–234,, 2007. 
Fontugne, M. and Duplessy, J.: Organic-carbon isotopic fractionation by marine plankton in the temperature range −1 to 31 C, Oceanol. Acta, 4, 85–90, 1981. 
Fox, J. and Weisberg, S.: An R companion to applied regression, Sage publications, 2018. 
Short summary
Carbon and nitrogen are essential elements for organisms; their stable isotope ratios (13C : 12C, 15N : 14N) are useful tools for understanding turnover and movement in the ocean. In the Sea of Japan, the environment is rapidly being altered by human activities. The 13C : 12C of small organic particles is increased by active carbon fixation, and phytoplankton growth increases the values. The 15N : 14N variations suggest that nitrates from many sources contribute to organic production.
Final-revised paper