Ecosystem respiration is an important component in global carbon cycling in terrestrial ecosystems. However, partitioning whole ecosystem respiration into its components is still a challenge, mainly due to the difficulty in direct measurements of ecosystem respiration and its components. We grew annual cheatgrass (Bromus tectorum L.) over one year in a unique facility EcoCELLS (Ecologically Controlled Enclosed Lysimeter Laboratory). Whole ecosystem carbon exchanges were continuously measured during this period including three stages: without plants seeded, with plants growing, and after plants harvested. Soil CO2 effluxes (RS) were also monitored continuously using an automated open-flow gas exchange system. Based on these data, we partitioned the whole ecosystem respiration (RE) into above-ground plant respiration (RA), soil organic matter-derived respiration (RH), and root-derived (or rhizosphere) respiration (RR).