Lake water salinity and periphytic diatom succession in three subarctic lakes, Yukon Territory

ABSTRACT. Seasonal changes in water chemistry and periphytic diatom assemblages were monitored for a saline, a subsaline, and a freshwater lake in the central Yukon Territory. Athalassic saline lakes, such as these, are believed to be extremely rare in arctic regions. All three study lakes exhibited...

Full description

Bibliographic Details
Main Authors: Allison J. Veres, Reinhard Pienitz, John P. Smol
Other Authors: The Pennsylvania State University CiteSeerX Archives
Format: Text
Language:English
Published: 1995
Subjects:
Online Access:http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.497.8279
http://pubs.aina.ucalgary.ca/arctic/arctic48-1-63.pdf
Description
Summary:ABSTRACT. Seasonal changes in water chemistry and periphytic diatom assemblages were monitored for a saline, a subsaline, and a freshwater lake in the central Yukon Territory. Athalassic saline lakes, such as these, are believed to be extremely rare in arctic regions. All three study lakes exhibited a gradual shoreline retreat over the season (28 May to 22 August 1992) due to evaporative water loss. As the season progressed, the saline lake exhibited a marked increase in conductivity and salinity, similar to changes observed for inland salt lakes in more southern regions. The seasonal changes in water chemistry were less pronounced in the subsaline and freshwater lakes. The periphytic diatom populations of the saline lake closely tracked changes in the lake’s salinity, exhibiting a successional shift from taxa with low salt tolerances (e.g., Nitzschia cf. commutata and N. cf. palea) to those with high salt tolerances (e.g., Amphora acutiuscula) over the study period. Periphytic diatoms in the subsaline and freshwater lakes also exhibited marked successional changes, shifting to almost complete dominance by a single species (Cocconeis placentula and Achnanthes minutissima respectively), but these shifts were not related to lake water salinity alone. Key words: lakes, diatoms, seasonal succession, saline, subarctic, Yukon RÉSUMÉ. On a observé les variations saisonnières dans la composition chimique de l’eau et les assemblages de diatomées périphytoniques, dans un lac salin, un lac subsalin et un lac d’eau douce dans le centre du Territoire du Yukon. On croit que de