Soil Biogeochemistry: Synthesis of Past Data and Development of Protocols for a New Long-Term, Network-Wide Data Stream

Summary We request funds for a working group to synthesize existing data within the LTER network on nitrogen mineralization and nitrification, soil respiration and soil moisture and to develop protocols for a new tightly coordinated, network-wide effort to develop a long-term data stream on these variables. The primary activity would be a workshop to be held at the Cary Institute of Ecosystem Studies. Key products include at least one synthesis paper and a protocol and program for new data collection going forward. Introduction Soil biogeochemistry is critical to ecosystem function and highly responsive to environmental change. Nitrogen mineralization and nitrification are key processes in the ecosystem nitrogen cycle and are critical controllers of net primary production, soil acidification and reactive nitrogen transport to water (nitrate) and air (nitrous oxide, nitric oxide). Soil respiration is a major pathway of carbon transport from ecosystems back to the atmosphere. Soil moisture is a critical regulator of these processes and is highly responsive to climate change. Indeed, the response of all these variables to environmental change is one of the key uncertainties in our ability to assess the trajectory of ecosystem structure, function and services in a changing world. Many LTER sites have made measurements of nitrogen mineralization, nitrification, soil respiration and soil moisture but with widely varying protocols. There is thus a strong need to assess the state of network-wide measurements of these variables and to develop a protocol for more coordinated data collection going forward.