Comparing ecosystem and soil respiration: Review and key challenges of tower-based and soil measurements

•Rsoil is a fraction of Reco and theoretically must be lower than Reco.•Reco was not consistently higher than Rsoil from daily to annual scales.•We discuss issues with current practices influencing under or overestimation of Reco and Rsoil.•Flux networks need a better integration of spatial and temporal variability of Reco and Rsoil.