TY - JOUR
T1 - The 13C method as a robust alternative to 14C-based measurements of primary productivity in the Mediterranean Sea
AU - López-Sandoval, Daffne C.
AU - Delgado-Huertas, Antonio
AU - Agusti, Susana
N1 - KAUST Repository Item: Exported on 2021-02-19
Acknowledged KAUST grant number(s): BAS/1/1072-01-01
Acknowledgements: ACKNOWLEDGEMENTS: We thank Arsenio Granados for his technical assistance during the mass spectrometric analysis of 13C-POCp and 13C-DIC samples. We also thank Narciso Algaba for providing training at the radioactive installation at the Estación Experimental del Zaidín, CSIC. We are grateful to the on-board UTM technician, the captain and crew of the R/V Garcia del Cid for all their collaboration and support during the cruise. FUNDING: This research was funded by the Ministerio de Economia, Industria y Competitividad through the project ARGON (grant CTM 2013–49429R). D.C.L.S. was supported by funding from the King Abdullah University of Science and Technology (KAUST), under award number (BAS/1/1072-01-01) assigned to S.A.
PY - 2018/8/11
Y1 - 2018/8/11
N2 - Due to the increasing constraints on using the radioactive isotope 14 C to measure primary productivity (14 C-PP), we determined the surface carbon fixation rates in the Mediterranean Sea, using the alternative stable isotope 13 C method (13 C-PP). Rates obtained (13 C-POCp) were compared with simultaneous 14 C-POCp measurements in samples of different volumes (72 mL and 1.2 L). We also tested the variation of the percentage of dissolved primary production (PER), to the total productivity using organic and inorganic filters (14 C method). 13 C-POCp rates ranged from 0.4, in the Ionian basin, to 1.5 mgC m -3 h -1 in the Ligurian region. These results agreed with those found with the 14 C-PP in 1.2-L samples (two sample t-test, t = 1.035, df = 22, P = 0.31). However, we found that 14 C-POCp rates derived from 72-mL incubations were 46% lower than those measured with 13 C-PP. The discrepancy between large and small volume incubations was likely due to differences in the number of large phytoplankton cells within the community. PER values measured with silver membrane filters yielded similar results than those obtained using polycarbonate filters. Our findings showed that when the sample size is carefully chosen, the 13 C-PP provide comparable results to 14 C-PP even in waters of low productivity in the Mediterranean Sea.
AB - Due to the increasing constraints on using the radioactive isotope 14 C to measure primary productivity (14 C-PP), we determined the surface carbon fixation rates in the Mediterranean Sea, using the alternative stable isotope 13 C method (13 C-PP). Rates obtained (13 C-POCp) were compared with simultaneous 14 C-POCp measurements in samples of different volumes (72 mL and 1.2 L). We also tested the variation of the percentage of dissolved primary production (PER), to the total productivity using organic and inorganic filters (14 C method). 13 C-POCp rates ranged from 0.4, in the Ionian basin, to 1.5 mgC m -3 h -1 in the Ligurian region. These results agreed with those found with the 14 C-PP in 1.2-L samples (two sample t-test, t = 1.035, df = 22, P = 0.31). However, we found that 14 C-POCp rates derived from 72-mL incubations were 46% lower than those measured with 13 C-PP. The discrepancy between large and small volume incubations was likely due to differences in the number of large phytoplankton cells within the community. PER values measured with silver membrane filters yielded similar results than those obtained using polycarbonate filters. Our findings showed that when the sample size is carefully chosen, the 13 C-PP provide comparable results to 14 C-PP even in waters of low productivity in the Mediterranean Sea.
UR - http://hdl.handle.net/10754/631502
UR - https://academic.oup.com/plankt/article/40/5/544/5071774
UR - http://www.scopus.com/inward/record.url?scp=85054296880&partnerID=8YFLogxK
U2 - 10.1093/plankt/fby031
DO - 10.1093/plankt/fby031
M3 - Article
C2 - 30279616
AN - SCOPUS:85054296880
VL - 40
SP - 544
EP - 554
JO - Journal of Plankton Research
JF - Journal of Plankton Research
SN - 0142-7873
IS - 5
ER -