2.1 Ecosystem respiration at UMBS. Daily mean total respiratory C loss (R-sigma) across seasons for UMBS, 1999-2003. Winter was day 1 – 129 and 280 – 365, early season was day 130 – 200, and late season was day 201 – 279 (Curtis et al., New Phytologist, 2005).

Quantifying C respiratory losses is a critical component of our research at UMBS~Flux. This is because C storage is equal to gross photosynthetic C assimilation minus C losses, principally from autotrophic and heterotrophic respiration. This balance between C assimilation and C respiration changes seasonally. Our data indicate that ecosystem respiration is highly variable across seasons at UMBS, largely in response to seasonal changes in temperature.