Fate of plant detritus in a European salt marsh dominated by Atriplex portulacoides (L.) Aellen

• Published in: Hydrobiologia 1998-01, Vol.373-374 (1-3), p.75-87
• Main Authors: Bouchard, V, Creach, V, Lefeuvre, J C, Bertru, G, Mariotti, A
• Format: Article
• Language: English
• Subjects: Atriplex portulacoides
• ISSN: 0018-8158
• DOI: 10.1007/978-94-011-5266-2_6

This paper deals with the organic matter dynamics of a dwarf shrub species, Atriplex portulacoides, which characterizes the majority of ungrazed European salt marshes. These dynamics were investigated by the simultaneous estimation of primary production, litter production, decomposition processes and accumulation of organic matter in sediment in the Bay of Mont-St. Michel, France. We used harvested biomass techniques and the litter-bag method, as well as more recent techniques such as determination of natural isotopic compositions. The results of this study have been compared with those of other studies of salt marshes of the Eastern Coast of America dominated by Spartina alterniflora. Studies of the fate of halophytic organic matter in salt marshes have shown that processes such as consumption, decomposition, or flooding rapidly could distribute organic material to different compartments of the marsh system. Aboveground productivity of A. portulacoides was 1700 g m super(-2) yr super(-1). Approximately 80% of this production was transformed rapidly in necromass.