Plant functional groups regulate soil respiration responses to nitrogen addition and mowing over a decade

1. Nitrogen (N) deposition and land-use practice (e.g. mowing) could have profound effects on soil respiration. However, the changes in other ecosystem components, such as plant functional groups (PFGs), may control soil carbon (C) efflux response to long term global change. 2. A 10-year (2005-2014) field experiment was conducted with both N addition (10g N m-2 yr-1) and mowing (once a year) in a northern Chinese temperate grassland. We collected continuous data on soil respiration over 10 years accompanied with data on abiotic and biotic factors, and attempted to determine (i) the temporal variation in soil respiration and its responses to N addition and mowing, (ii) the regulation of soil respiration by PFGs and the underlying long-term mechanisms of control. 3. Soil respiration varied significantly among years. This was mainly caused by changes in precipitation pattern (e.g. frequency and distribution) during the growing-season rather than total rainfall. N addition significantly sup...