TAXONOMIC AND ECOLOGICAL CHARACTERIZATION OF CHRYSOPHYTE STOMATOCYSTSFROM NORTHWESTERN CANADA

Chrysophyte stomatocysts from the surface sediments of 49 lakes locate d on a north-south transect in the Yukon and Northwest Territories, Ca nada, were investigated for their potential use as indicators of envir onmental change in northern latitudes. Photographic plates and descrip tions, following International Statospore Working Group guidelines, il lustrate 19 new stomatocyst morphotypes. The main patterns of floristi c variation in the data set were explored using canonical corresponden ce analysis, which indicated that gradients of chloride (r(2) = 0.73), dissolved inorganic carbon (r(2) = 0.63), and surface-water temperatu re (r(2) = 0.55) were important in influencing species assemblages. Co mpared with the diatom-temperature inference model developed from the same set of lakes, the stomatocysts provided a slightly less robust mo del. These results suggest that stomatocysts are weakly, though signif icantly, related to some of the gradients in lake water chemistry in t his data set and can provide a complement to other paleoecological mar kers.