Open AccessDistribution and diversity of diatom assemblages in surficial sediments of shallow lakes in Wapusk National Park (Manitoba, Canada) region of the Hudson Bay Lowlands
Author(s) -
Jacques Olivier,
Bouchard Frédéric,
MacDonald Lauren A.,
Hall Roland I.,
Wolfe Brent B.,
Pienitz Reinhard
Publication year - 2016
Publication title -
ecology and evolution
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.17
H-Index - 63
ISSN - 2045-7758
DOI - 10.1002/ece3.2179
Subject(s) - diatom , subarctic climate , bay , paleolimnology , oceanography , ecology , lake ecosystem , algae , national park , environmental science , ecosystem , geology , physical geography , geography , biology
The hydrology of shallow lakes (and ponds) located in the western Hudson Bay Lowlands ( HBL ) is sensitive to climate warming and associated permafrost thaw. However, their biological characteristics are poorly known, which hampers effective aquatic ecosystem monitoring. Located in northern Manitoba along the southwestern coast of Hudson Bay, Wapusk National Park ( WNP ) encompasses numerous shallow lakes representative of the subarctic zone. We analyzed the distribution and diversity of diatom (microscopic algae; class Bacillariophyceae) assemblages in surficial sediments of 33 lakes located in three different ecozones spanning a vegetation gradient, from NE to SW : the Coastal Fen ( CF ), the Interior Peat Plateau ( IPP ), and the Boreal Spruce Forest ( BSF ). We found significant differences ( P < 0.05) in diatom community composition between CF and IPP lakes, and CF and BSF lakes, but not between IPP and BSF lakes. These results are consistent with water chemistry measurements, which indicated distinct limnological conditions for CF lakes. Diatom communities in CF lakes were generally dominated by alkaliphilous taxa typical of waters with medium to high conductivity, such as Nitzschia denticula . In contrast, several IPP and BSF lakes were dominated by acidophilous and circumneutral diatom taxa with preference for low conductivity (e.g., Tabellaria flocculosa , Eunotia mucophila , E. necompacta var. vixcompacta ). This exploratory survey provides a first detailed inventory of the diatom assemblages in the WNP region needed for monitoring programs to detect changes in shallow lake ecosystems and ecozonal shifts in response to climate variations.