Building Flux Capacity: Citizen Scientists Increase Resolution of Soil Greenhouse Gas Fluxes.

Citizen science has long been recognized as a valuable means to increase sampling intensity or frequency while simultaneously improving scientific literacy and participation. But at present, there are few examples of soil scientists and biogeochemists partnering with citizen scientists to answer research questions. Here, we present results from a case study in which we demonstrate the feasibility and success of partnering with citizen scientists to measure greenhouse gas fluxes in high elevation Sierra Nevada meadows. We sought to increase our understanding of spatial and diel fluxes in these meadows while minimizing sampling error while maximizing the “fun factor” for our participants. With the assistance of a dozen citizen scientists, we measured greenhouse gas fluxes at 52 points simultaneously. A subset of eight volunteers stayed to measure greenhouse gas fluxes every two hours for 24 hours. Soil carbon dioxide, methane, and nitrous oxide fluxes were spatially independent of each other from 1.5 meters to beyond 50 meters, suggesting that the spatial controls on these fluxes occur at the sub-meter scale (and reflecting the microbial controls of these processes). Similarly, we saw no significant change in any greenhouse gas flux throughout our 24-hour sampling period. Our sampling error associated with citizen scientist participation increased to ~2% from the < 1% error typically incurred when soil fluxes are sampled by graduate students only. However, this increase was offset by ~9x higher spatial resolution and 12x higher temporal resolution beyond what is typically possible in a normal sampling campaign. Post-project survey results suggest that volunteers enjoyed the experience and learned about soil biogeochemistry in the process. Our case study demonstrated that citizen scientists can be a valuable addition to soil science research.