Written by Robin Glas, John Russell Slosson, and Alexa Stathis

Greenhouse gases like methane and carbon dioxide don’t just reside in our atmosphere; they are constantly moving through the soil as well.  Plants and microbes underground are undergoing respiration and other processes that can significantly affect the health of an environment, “breathing out” and producing these gases that are then released into the atmosphere.  Students in the EMPOWER Water-Energy Seminar recently discussed soil gas exchanges and how movement of certain gases through the soil could be affected by climate change.  The students learned about how to measure these gases in the soil at different scales: from small probes that can be inserted into the soil, to meter- scale chambers that capture gases moving in and out of the soil, to larger scale measurements that involve atmospheric circulation.  This was the students’ first glimpse into some of the methods they will be using this upcoming summer, when they will complete a field course in the Hubbard Brook Experimental Forest, which is in the White Mountains of New Hampshire.

Students also read the article Climate Variation and Soil Carbon and Nitrogen Cycling Processes by Groffman et al. (2009), which used changes in elevation as a proxy for the climatological changes expected to occur with warming temperatures in the Hubbard Brook Experimental Forest. Students considered some of the challenges of using this model to simulate climate change in soil processes. Students also discussed the broader implications of the research, including possible increased susceptibility of soils to freezing in warmer temperatures due to the loss of insulating snowpack and lowered rates of nitrogen mineralization and nitrification.