The Vegetation of Salt Marshes at Some Coastal Sites in Arctic North America

SUMMARY The vegetation of salt marshes was examined at seven sites on the Arctic coast of Alaska and Canada, at some of which measurements were made of the salinity of sea water, the amounts of standing crop of the vegetation and the distribution of biomass within plants. Puccinellia phryganodes, Stellaria humifusa and Cochlearia officinalis form the pioneer plant community on open coasts, but in sheltered bays and inlets, where vegetation cover is continuous, species such as Arctophila fulva, Dupontia fisheri, Hippuris tetraphylla and Carex ramenskii are frequent. The salinity of inshore sea water at most sites is very low. In this survey salinity values do not exceed 0 27 M Na+ (c. 18%/,). The total biomass for stands of the pioneer plants also is low (96-284 g m 2). The above-ground :below-ground ratios of dry matter lie between 1 :0 11 and 1:3 340. A tentative estimate of the net primary production of Puccinellia phryganodes indicates that a value of 10 g m-2 per annum appears to be an upper limit. The results are compared with similar data from Polar regions in North America and Eurasia.