Original paper
Effects of natural dissolved organic matter on mucilaginous matrices of biofilm communities
Wetzel, Robert G.; Ward, Amelia K.; Stock, Marsha
Archiv für Hydrobiologie Volume 139 Number 3 (1997), p. 289 - 299
33 references
published: Jun 6, 1997
DOI: 10.1127/archiv-hydrobiol/139/1997/289
ArtNo. ESP141013903000, Price: 29.00 €
Abstract
We evaluated experimentally the effects of dissolved organic carbon (DOC) derived from leachates of decomposing emergent macrophytes (Typha latifolia) on mucilage development in periphyton communities. Several techniques were used to quantify mucilage development by natural periphyton communities grown on glass fiber filters and on sand in a defined culture medium with and without exposure to humic acid fractions of the leachate (up to 20 mg C L-1): (a) direct examination by cryogenic scanning electron microscopy (SEM), (b) application of a cationic copper-containing dye, Alcian Blue 8GX, which binds to the glycosaminoglycans in the mucilage, and determination of the relative quantity of copper retained by the community by energy dispersive X-ray microanalyses, and (c) amounts of dye removed from solution by spectrophotometric analyses. Multiple experiments showed that DOC-treated communities contained 10 to 57 % less mucilage than untreated controls, and suggested that DOC in littoral and wetland environments can act as an important physical determinant of structural and metabolic attributes of periphyton.
Keywords
periphyton • mucilage • glycosaminoglycans • wetland • environment