Biogeography of high-latitude macroalgal flora: Greenland macroalgal diversity in a North Atlantic and macroecological perspective 

Abstract

Marine flora distribution change modelling is of high interest in order to investigate the implications of ocean warming due to climate changes. With respect to the Arctic, Greenland is a major player, but due to limited floristic data, including sporadic and difficult accessible historical data, public available data is lacking. Here is presented the Greenland macroalgal flora diversity and distribution, providing a baseline, based on historical and present knowledge, and analyse the distributional patterns within Greenland, but also in a Polar and North Atlantic perspective. Species presence and distribution in Greenland are compiled from literature and from species lists prepared by Greenland macroalgae taxonomists. Macroalgal species numbers are compiled from literature for other countries/regions represented in the North Atlantic. The data set has been analysed in a national biogeographic context, as well as in a polar macroecological perspective, using the (R + C)/P index. A total macroalgal species number of 176 species, divided into 49 Rhodophyta, 79 Phaeophyceae, and 48 Chlorophyta species, were found for Greenland, distributed along a latitudinal gradient from 60-83°N, and whereas 134 and 144 species were registered for the east and west coast, respectively. In general, a linear decline in species number from south to north was observed, as well as on the transverse transect in the northern North Atlantic, with a general higher fraction of Phaeophycean species in the north. A distributional baseline and a checklist for the Greenland macroalgal flora are provided.