Tissue Nitrogen and Carbon Variations in New England Estuarine Ascophyllum nodosum (L.) Le Jolis Populations (Fucales, Phaeophyta)

Abstract

The seasonal patterns ofAscophyllum nodosum (L.) Le Jolis tissue composition (N, C and ash) and ambient inorganic N were measured for 18 months at seven sites throughout the Great Bay Estuary System, New Hampshire-Maine, U.S.A. Overall, the seasonal cycle of tissue N coincided with ambient dissolved inorganic N, with low values in the late spring and summer and highest values in late fall and winter. even so, a pronounced lag occurred in the spring when ambient nutrients decreased, and the levels of tissue N remained high. The seasonal patterns of tissue N were very similar throughout the estuary, although the spring maxima were conspicuously greater at inner than outer estuarine sites. No conspicuous seasonal trend was apparent for tissue C, and the C/N ratios merely reflected variation in N. The percent ash values were extremely variable, and they did not reflect a simple salinity gradient within the Estuary. Two examples of the potential significance ofAscophyllum to the nitrogen pools in northern New England estuaries are discussed.