Korosi, JenniferColeman, KristenThienpont, JoshuaPalmer, Michael2025-04-232025-04-232025https://hdl.handle.net/10315/42896Small, shallow lakes were sampled in the southern Northwest Territories, Canada, distributed in the Taiga Plains Mid-Boreal Level III Ecoregion (South Mackenzie Plain, Tathlina Plain) and the Taiga Plains High Boreal Level III Ecoregion (Cameron Uplands).Lake browning has been widely projected for northern lakes affected by permafrost thaw, but the inherent heterogeneity in permafrost landscapes coupled with a paucity of data for many regions makes it challenging to develop circumpolar-scale assessments. This dataset provides surface water chemistry from 35 small, shallow (0.5-3 m) lakes in discontinuous permafrost peatlands of the Taiga Plains (Northwest Territories, Canada), which were distributed across two Level IV ecoregions (Cameron Uplands, Tathlina Plain). This dataset also provides a comparison subfossil diatom assemblages between present-day (2012-2018) and ~1850 in 23 Taiga Plains lakes distributed across three Level IV ecoregions (Cameron Uplands, Tathlina Plain, South Mackenzie Plain).Attribution-NonCommercial-ShareAlike 4.0 InternationalLake water chemistry210Pb dating of lake sediment coresDiatom subfossil assemblagesDataset