Oxidation of sulfide by Spartina alterniflora roots

Abstract

Root tips from the marsh grass Spartina alterniflora , collected from areas of high and low pore‐water sulfide, exhibited a substantial capacity to catalyze sulfide oxidation, as determined by closed‐chamber respirometry. A large proportion of this catalysis was apparently nonenzymatic and was higher in roots of plants from the high‐sulfide versus the low‐sulfide site. Activity exhibiting characteristics of enzymatic sulfide oxidation was significantly higher in plants from the low‐sulfide site. Results from elemental analysis of root tissue were consistent with the theory that metals play a role in nonenzymatic catalysis. These results indicate that estuarine plants may detoxify environmental sulfide via sulfide oxidation.