Facts about Salt Marshes

1. 12

   Nitrogen-fixing bacteria in salt marsh soils convert atmospheric nitrogen into bioavailable forms, increasing soil fertility by up to 300 percent compared to adjacent upland areas.

   Salt MarshesMay 14sharemicrobiologychemistrynutrientcycling
2. 11

   A single acre of salt marsh can produce 10 tons of plant biomass annually, supporting food webs that sustain migratory birds traveling thousands of miles each year.

   Salt MarshesMay 14sharebiologyproductivitymigration
3. 10

   Microorganisms in salt marsh sediments produce dimethyl sulfide, a volatile compound that influences cloud formation and regional climate patterns across coastal areas.

   Salt MarshesMay 14sharechemistrymicrobiologyclimate
4. 09

   Approximately 45 percent of salt marsh losses in the United States occur in Louisiana, where subsidence and Mississippi River diversions cause the landscape to sink faster than sediment can accumulate.

   Salt MarshesMay 14sharegeographymeasurementerosion
5. 08

   Salt marsh vegetation can trap and store heavy metals like cadmium and lead from polluted waters, with some plants accumulating concentrations 100 times higher than surrounding sediment.

   Salt MarshesMay 14sharebioaccumulationchemistryecology
6. 07

   Tidal pumping in salt marshes can move water vertically through sediment layers up to 1 meter deep, creating biogeochemical gradients that support distinct microbial communities.

   Salt MarshesMay 14sharehydrologymicrobiologychemistry
7. 06

   Over 3,000 species of fish and crustaceans depend on salt marshes during some life stage, with commercially valuable species like blue crabs spending their juvenile years in these coastal nurseries.

   Salt MarshesMay 14sharebiologyecologyeconomics
8. 05

   Diamondback terrapins use salt marshes as nurseries, with females returning to the same marsh where they hatched decades earlier to lay eggs.

   Salt MarshesMay 14sharebiologyreproductionbehavior
9. 04

   Between 1980 and 2020, approximately 25 percent of global salt marshes disappeared due to coastal development and sea-level rise.

   Salt MarshesMay 14shareconservationmeasurementgeography
10. 03

    Every tidal cycle, salt marshes filter sediment and nutrients from tidal waters, reducing downstream coastal pollution by up to 90 percent.

    Salt MarshesMay 13shareecologywaterfiltration
11. 02

    Spartina alterniflora, the dominant grass species in Atlantic salt marshes, can tolerate salinity levels five times higher than typical seawater.

    Salt MarshesMay 13sharebiologyadaptationchemistry
12. 01

    Globally, salt marshes sequester approximately 1.5 metric tons of carbon per hectare annually, making them crucial climate regulators.

    Salt MarshesMay 13sharebiologymeasurementclimate