Ecological Survey of Thaw Depth, Soil Organic Layer Thickness, Plant Functional Types, and Vegetation Height around an Eddy Covariance Tower at a Council, Alaska Tundra Site (June 2025)

An ecological survey was conducted June 24th - June 30th, 2025 to characterize the landscape around an eddy covariance tower site located in the Seward Peninsula near Council, Alaska (64.8618, -163.7008). The tower was initially established and operated by Next-Generation Ecosystem Experiments (NGEE) - Arctic from 2017 - 2019 (Ameriflux site ID: US-NGC); a new tower was established in 2024 by Woodwell Climate Research Center and is now operated by Woodwell as part of the Permafrost Pathways Arctic Carbon Monitoring program (Ameriflux site ID: CAK). All eddy covariance tower measurements are available on the Ameriflux website. The Council site is described as wet meadow tussock tundra with discontinuous permafrost. Low-lying areas with thaw ponds and thermokarst channels support wet-sedge meadow communities, and the surrounding level plain is comprised of tussock tundra vegetation (Eriophorum vaginatum) with low shrubs (Betula nana, Empetrum nigrum, Arctostaphylos spp., Rubus chamaemoris, Salix arctica, Salix glauca, Vaccinium spp.), bordered by riparian white spruce (Picea glauca) woodlands. Sampling plots were established every 10 - 20 meters (m) along 100 m transects extending north, east, south, and west from the tower and include thaw depth and vegetation surveys of 50 centimeter (cm) x 50 cm plots. Soil organic layer thickness measurements and organic layer soil cores were taken from dominant landscape and vegetation community types near the EC tower.