Peatland bogs are wetlands which accumulate massive amounts of organic matter over centuries due to the growth, death, and buildup of mosses and other plants. These bogs are often water-logged and very cold, which prevents the microbes living in the peat from decomposing the dead plants more quickly than they can build up. Previous experiments at a northern peatland bog show that when it’s warmer or drier there is increased decomposition. However, the experimental plots which are the warmest also tend to be the driest, so it’s hard for us to know if the increases in carbon loss are more from the temperature or the moisture changes.

In our experiment, we collected peat to incubate over 70 days in jars in the lab at three different temperature and moisture levels so that we can understand how each affects peat decomposition, both separately and together. We measure carbon dioxide production by microbes as they break down the peat to determine carbon loss over time. So far, we’ve found that increased temperature and decreased moisture accelerated the rate of carbon dioxide production, suggesting that future warmer temperatures and increased drought frequency might put peatland ecosystems at risk for accelerated carbon loss.