Biogeosciences (Apr 2021)
Hypersaline tidal flats as important “blue carbon” systems: a case study from three ecosystems
- D. R. Brown,
- H. Marotta,
- H. Marotta,
- H. Marotta,
- R. B. Peixoto,
- R. B. Peixoto,
- A. Enrich-Prast,
- A. Enrich-Prast,
- A. Enrich-Prast,
- G. C. Barroso,
- M. L. G. Soares,
- W. Machado,
- A. Pérez,
- A. Pérez,
- J. M. Smoak,
- L. M. Sanders,
- S. Conrad,
- J. Z. Sippo,
- J. Z. Sippo,
- J. Z. Sippo,
- I. R. Santos,
- I. R. Santos,
- D. T. Maher,
- D. T. Maher,
- D. T. Maher,
- C. J. Sanders,
- C. J. Sanders
Affiliations
- D. R. Brown
- National Marine Science Centre, School of Environment, Science and Engineering, Southern Cross University, P.O. Box 4321, Coffs Harbour, NSW, 2450, Australia
- H. Marotta
- Ecosystems and Global Change Laboratory (LEMG-UFF), International Laboratory of Global Change (LINCGlobal), Biomass and Water Management Research Center (NAB), Universidade Federal Fluminense, Av. Edmundo March, s/n extdegree, Niterói, RJ, 24210-310, Brazil
- H. Marotta
- Graduate Program in Geosciences (Environmental Geochemistry), Department of Geochemistry, Universidade Federal Fluminense, Niterói, RJ, 24020-141, Brazil
- H. Marotta
- Physical Geography Laboratory (LAGEF-UFF), Department of Geography, Graduate Program in Geography, Universidade Federal Fluminense, Av. Gal. Milton Tavares de Souza, s/no., Niterói, RJ, 24210-346, Brazil
- R. B. Peixoto
- Ecosystems and Global Change Laboratory (LEMG-UFF), International Laboratory of Global Change (LINCGlobal), Biomass and Water Management Research Center (NAB), Universidade Federal Fluminense, Av. Edmundo March, s/n extdegree, Niterói, RJ, 24210-310, Brazil
- R. B. Peixoto
- Graduate Program in Geosciences (Environmental Geochemistry), Department of Geochemistry, Universidade Federal Fluminense, Niterói, RJ, 24020-141, Brazil
- A. Enrich-Prast
- Ecosystems and Global Change Laboratory (LEMG-UFF), International Laboratory of Global Change (LINCGlobal), Biomass and Water Management Research Center (NAB), Universidade Federal Fluminense, Av. Edmundo March, s/n extdegree, Niterói, RJ, 24210-310, Brazil
- A. Enrich-Prast
- Department of Thematic Studies – Environmental Change, Linköping University, 581 83, Linköping, Sweden
- A. Enrich-Prast
- Department of Botany, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, 21941-902, Brazil
- G. C. Barroso
- Graduate Program in Geosciences (Environmental Geochemistry), Department of Geochemistry, Universidade Federal Fluminense, Niterói, RJ, 24020-141, Brazil
- M. L. G. Soares
- Laboratory For Mangrove Studies (NEMA-UERJ), International Laboratory of Global Change (LINCGlobal) and Interdisciplinary Observatory on Climate Change (OIMC-UERJ), Department of Biological Oceanography, Faculty of Oceanography, Universidade do Estado do Rio de Janeiro (UERJ), Rua São Francisco Xavier, 524, sala 4019-E, Rio de Janeiro, RJ, 20550-900, Brazil
- W. Machado
- Graduate Program in Geosciences (Environmental Geochemistry), Department of Geochemistry, Universidade Federal Fluminense, Niterói, RJ, 24020-141, Brazil
- A. Pérez
- Graduate Program in Geosciences (Environmental Geochemistry), Department of Geochemistry, Universidade Federal Fluminense, Niterói, RJ, 24020-141, Brazil
- A. Pérez
- Laboratorio de Biogeociencias, Laboratorios de Investigación y Desarrollo (LID), Facultad de Ciencias y Filosofía, Centro de Investigación para el Desarrollo Integral y Sostenible (CIDIS), Universidad Peruana Cayetano Heredia, Av. Honorio Delgado 430, Urb. Ingeniería, Lima, Peru.
- J. M. Smoak
- School of Geosciences, University of South Florida, St. Petersburg, FL 33701, USA
- L. M. Sanders
- Southern Cross GeoScience, Southern Cross University, P.O. Box 157, Lismore, NSW, 2480, Australia
- S. Conrad
- National Marine Science Centre, School of Environment, Science and Engineering, Southern Cross University, P.O. Box 4321, Coffs Harbour, NSW, 2450, Australia
- J. Z. Sippo
- National Marine Science Centre, School of Environment, Science and Engineering, Southern Cross University, P.O. Box 4321, Coffs Harbour, NSW, 2450, Australia
- J. Z. Sippo
- Southern Cross GeoScience, Southern Cross University, P.O. Box 157, Lismore, NSW, 2480, Australia
- J. Z. Sippo
- School of Environment, Science and Engineering, Southern Cross University, P.O. Box 157, Lismore, NSW, 2480, Australia
- I. R. Santos
- National Marine Science Centre, School of Environment, Science and Engineering, Southern Cross University, P.O. Box 4321, Coffs Harbour, NSW, 2450, Australia
- I. R. Santos
- Department of Marine Sciences, University of Gothenburg, Gothenburg, Sweden
- D. T. Maher
- National Marine Science Centre, School of Environment, Science and Engineering, Southern Cross University, P.O. Box 4321, Coffs Harbour, NSW, 2450, Australia
- D. T. Maher
- Southern Cross GeoScience, Southern Cross University, P.O. Box 157, Lismore, NSW, 2480, Australia
- D. T. Maher
- School of Environment, Science and Engineering, Southern Cross University, P.O. Box 157, Lismore, NSW, 2480, Australia
- C. J. Sanders
- National Marine Science Centre, School of Environment, Science and Engineering, Southern Cross University, P.O. Box 4321, Coffs Harbour, NSW, 2450, Australia
- C. J. Sanders
- State Key Laboratory of Estuarine and Coastal Research, East China Normal University, Shanghai 201100, P.R. China
- DOI
- https://doi.org/10.5194/bg-18-2527-2021
- Journal volume & issue
-
Vol. 18
pp. 2527 – 2538
Abstract
Hypersaline tidal flats (HTFs) are coastal ecosystems with freshwater deficits often occurring in arid or semi-arid regions near mangrove supratidal zones with no major fluvial contributions. Here, we estimate that organic carbon (OC), total nitrogen (TN) and total phosphorus (TP) were buried at rates averaging 21 (±6), 1.7 (±0.3) and 1.4 (±0.3) gm-2yr-1, respectively, during the previous century in three contrasting HTF systems, one in Brazil (eutrophic) and two in Australia (oligotrophic). Although these rates are lower than those from nearby mangrove, saltmarsh and seagrass systems, the importance of HTFs as sinks for OC, TN and TP may be significant given their extensive coverage. Despite the measured short-term variability between net air–saltpan CO2 influx and emission estimates found during the dry and wet season in the Brazilian HTF, the only site with seasonal CO2 flux measurements, the OC sedimentary profiles over several decades suggest efficient OC burial at all sites. Indeed, the stable isotopes of OC and TN (δ13C and δ15N) along with C:N ratios show that microphytobenthos are the major source of the buried OC in these HTFs. Our findings highlight a previously unquantified carbon as well as a nutrient sink and suggest that coastal HTF ecosystems could be included in the emerging blue carbon framework.
