Howarth 1979

Howarth RW. 1979. Pyrite: Its rapid formation in a salt marsh and its importance in ecosystem metabolism. Science 203: 49-51.

This author investigated sulfur and iron dynamics in a salt marsh in the United States. Previous work by other authors had suggested pyrite (FeS2), one end-product in sulfur reduction, forms slowly over years or decades in marine sediments. This paper includes an experiment involving buried Teflon bags in which pyrite formation was detected after 48 hours. From this and other measurements, an estimate of total marshland bacterial sulfur-driven respiration was formed that is of a similar magnitude in CO2 release as is total net productivity of the marshland.

Iron metabolism in this system involves formation of amorphous iron compounds under oxidizing conditions, with a predominance of crystalline forms only under more reducing conditions.