Under-ice water chemistry and plankton community data collected at the onset of spring thaw in four arsenic-contaminated subarctic lakes in 2022 and 2023

The objective of this study was to assess and compare arsenic biogeochemical processes and plankton communities at the late winter to spring thaw transition period in four Yellowknife-area lakes (Northwest Territories, Canada) that span a gradient of arsenic contamination. Interactions between aquatic organisms and contaminants in under-ice lake environments are poorly characterized relative to ice-free seasons. In particular, the spring thaw transition is a potentially significant but understudied period of rapid biological and chemical change. We collected water chemistry data as well as community data for phytoplankton, rotifer, zooplankton in late April and early May of 2022 and 2023.