2025 Wetland Accretion Measurements from Smithsonian Environmental Research Center SMARTX Warming Plots

Sediment accretion measurements were made at the SMARTX warming experiment at the Smithsonian Environmental Research Center's Global Change Research Wetland. Feldspar marker horizons were established at the beginning of the experiment in 2016 in the warming plots, and were subsequently buried over time by wetland accretion of both organic and inorganic matter. These data include the measurements (via cryogenic coring) of the depth to the marker horizon layer, which can be used to calculate the accretion rate of the wetland, and the organic content of the accretion material, which was determined via Loss On Ignition. These data reflect the accretion of the different vegetation communities (C3 vs. C4) and temperature gradients (+1.7C, +3.4C, +5.1C, ambient) and atmospheric CO2 conditions (elevated CO2 vs. control).