Environmental sensor data in acidic and non-acidic tundra, Toolik, Alaska (2021-2022)

The motivation of this study was to assess how environmental conditions varied seasonally and specially across tundra hillslopes underlain with permafrost near Toolik Lake, Alaska. The research took place in the thaw seasons of 2021 and 2022 at two tundra hillslopes (acidic and non-acidic tundra) near Toolik Lake, each with sites along a moisture gradient (dry, mesic, and wet), with three replicate 5 x 5 meter (m) plots at each site. Dataloggers (CR-300 and CR-1000, Campbell Scientific) were deployed at each site to record continuous measurements from Triscan probes (soil temperature, salinity, and moisture measurements) (n = 1 per site), and Paleoterra redox potential probes referenced to potassium chloride (KCl)-saturated silver chloride/silver (AgCl/Ag0) electrodes (N = 3 per site). Soil temperature (degrees Celsius [ºC]), moisture (percent [%]), salinity (microsiemens per centimeter [µS cm-1]), and redox potential (megavolts [mV]) were measured during the 2021 thaw seasons at 15-minute timesteps. Temperature, moisture, and salinity measurements were recorded over three depth intervals (0 - 10 centimeter [cm], 10 - 20 cm, and 20 - 30 cm) while redox potential was recorded at four depths down to 30 cm in dry and mesic sites and eight depths in wet sites down to 60 cm. Platinum sensors on each probe were 2 millimeters [mm] thick and placed at 5 cm, 10 cm, 20 cm, and 30 cm (probes used for dry/mesic sites) or 2 cm, 4 cm, 6 cm, 8 cm, 10 cm, 20 cm, 40 cm, and 60 cm (probes used for wet sites) from the top of the redox probe.