Carbohydrate sources in a coastal marine environment

Individual neutral sugars in sediments, sediment trap materials and major biological sources of a coastal marine environment (Dabob Bay, Washington State) were analyzed by capillary gas chromatography of equilibrated isomeric mixtures. Plankton, bacteria, and vascular plant tissues of different types yielded reproducible and biochemically consistent compositional patterns. These patterns, when expressed in simple parameters, allowed distinctions between marine and terrestrial carbohydrate sources as well as among the major different types of vascular plant tissues. Plankton and bacteria, due to their compositional diversity, were not further distinguishable by carbohydrate compositions alone. Carbohydrate compositions of Dabob Bay sediments and sediment trap materials, interpreted using source-indicator parameters, indicate a predominantly marine origin with increased relative input of terrestrially-derived carbohydrates in winter periods of low phytoplankton productivity. Both plankton and grasses are indicated as major carbohydrate sources during spring. Glucose yield enhancement factors, determined by comparative acid pretreatments, confirm the general predominance of α-cellulose-poor marine polysaccharides and increased levels of α-cellulose-rich vascular plant remains in winter sediment trap samples.