The Salt Marsh Ecosystem

Abstract

Highly productive salt marsh grass ecosystems, such as those of Spartina alterniflora, Juncus roemerianus, and Phragmites australis, characterize temperate and high-latitude regions. Endophytic fungi, phylloplane fungi, and weak parasites inhabit healthy and senescent salt marsh grass plants. Dead parts of salt marsh plants are colonized by a large diversity of obligate and facultative marine, mycetaen fungi. Most of the decomposition takes place while the plant parts are still attached to the living plants. Fungal diversity in decomposing salt marsh grass is influenced by the host species, plant part, vertical zonation, and the stage of decomposition. Decay is characterized by leaching, mass loss, and lignocelluloses degradation. Fungal biomass comprises a significant portion of more than 20% of the total dry weight to standing, decomposing salt marsh grass. Bacteria prevail once the decomposed leaves fall into the sediment and fragment. Straminipilan fungi may colonize fragmented detritus in salt marshes. Complete decay and fragmentation may take over a year. The high fungal biomass and microbial nitrogen enrichment make salt marsh grass detritus highly palatable and nutritious to detritivores.