Salt Marshes

  • Daniel M. Alongi
Part of the SpringerBriefs in Climate Studies book series (BRIEFSCLIMATE)


Salt marshes are intertidal wetlands that occur on low-energy shores and are comprised of herbaceous flowering plants and small scrubs. Salt marshes sequester and store large quantities of blue carbon. Soil accretion rates range from 2 to 10 mm year-1 with a median of 5 mm year-1. Carbon sequestration rates in salt marshes show no clear relationship with latitude as these rates are a function of interrelated factors such as marsh age, tidal inundation frequency, tidal elevation, marsh geomorphology, species composition, soil grain size, catchment and river input, ocean input and degree of human impact. The mean sequestration rate is 212 ± 18 g Corg m−2 year−1. The stocks of soil carbon in marshes averages 317.2 ± 19.1 Mg Corg ha−1 with a median of 282.2 Mg Corg ha−1 and a total global estimate of 1.2 Pg Corg. On average, 99.2% of carbon is vested in soils and roots. The loss of carbon shifts marshes from net sinks to net sources of carbon for the atmosphere. Losses of salt marsh equate to 1.1 Pg CO2 equivalents returned to the atmosphere or coastal ocean since the 1800s.


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© The Author(s) 2018

Authors and Affiliations

  • Daniel M. Alongi
    • 1
  1. 1.Tropical Coastal & Mangrove ConsultantsAnnandaleAustralia

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