Partitioning the Components of Soil Respiration in a Trenching Experiment at Harvard Forest since 2011

Total soil respiration (Rt) is a combination of autotrophic (Ra) and heterotrophic respiration (Rh). We used a trenching method to sever the rooting system surrounding a plot to remove the Ra component within the plot. We used a custom-made automated chamber system to measure soil respiration within the trenched plot and the control in an oak dominated forest with the footprint of the LPH tower. This method has some potential limitations. Reduced water uptake in trenched plots could change soil water content, which is one of the environmental controllers of Rt in many ecosystems. Eliminating root inputs could reduce heterotrophic decomposition of SOM via lack of priming.