Investigation of the marine macrophytes at Black Rock, Kings Co., N.S.

The littoral algal biomass and zonation at Black Rock, Kings Co., Nova Scotia, were investigated. Data were collected in June 1978 from five transects. The average wet weight for all transects was 2616.7 g/m². The average dry and carbon weights for all transects were 551.9 g/m² and 213.6 g/m² respectively. Thus the total dry weight was 21.1% of the total wet weight, and the total carbon weight was 8.2% of the total wet weight. Eleven species of algae were collected. Ascophyllum nodosum (L.) Le. Jol. comprised 88.7% of the total carbon weight while Gigartina stellata (Stack.) Batt. (5.58) and Fucus vesiculosus L. (4.3%) were next in abundance. The species diversity increased from the upper beach toward datum. Two zones of littoral macrophytic algae were evident; the Ascophyllum zone and the Gigartina zone. The Ascophyllum zone was between two and five meters above datum and the Gigartina zone was between datum and two meters above datum. The algal biomass of two kilometers of beach, in the Black Rock area, was estimated to be 780 metric tonnes wet weight and 60 metric tonnes carbon weight.