Sakinaw Lake

A stratified lake ecosystem.

Ecosystem Type: Permanently stratified lake
Location: Sunshine Coast, British Columbia (49°41’02.4″N, 124°00’07.2″W)

Sakinaw Lake on the Sunshine Coast of British Columbia is a permanently stratified, or meromictic lake that hosts a high proportion of uncultivated microbial dark matter (MDM) lineages implicated in methane cycling processes. By studying MDM in the Sakinaw Lake water column we hope to uncover ecological design principles driving distributed metabolism under low energy conditions that can be applied to the development of anaerobic digestion processes for renewable biogas production.  

Microbial community structure along the Lake’s gradients follows patterns similar to those of other meromictic lakes, including sulfate-reducing bacteria at the top of a pronounced sulfate-methane transition zone and a steady increase in the relative abundance of Chloroflexi with depth. Uniquely, however, in the upper portion of the transition zone between the fresh and saline basins in Sakinaw Lake (36 m), the abundance of microbial dark matter lineages, including uncharacterized populations of Archaea, increases dramatically to encompass nearly half of marker gene sequences. Thus, the magnitude of uncharacterized microbial populations in Sakinaw lake provides an opportunity to chart the metabolic properties and potential interactions of many uncultivated lineages in a relatively accessible manner.