Home-field advantage meets priming effect in root decomposition: Implications for belowground carbon dynamics

1. Home-field advantage (HFA) states that litter decomposes faster in ‘home’ than in ‘away’ soil, due to the specialization of decomposer organisms in decomposing litter derived from their local plant community. Demonstration of the HFA effect has been overwhelmingly based on aboveground leaf litter despite the fact that roots play a pivotal role in carbon (C) and nutrient cycling.
2. Labile C input in root exudates and newly shed root litters can enhance the activity of soil microorganisms, which in turn can favor the breakdown of older root litter, also referred to as the priming effect. It remains, however, unclear how the addition of fresh root-derived inputs affects HFA on the decomposition of absorptive roots (ARs) and transport roots (TRs), which have a different chemical composition.
3. Here, we conducted a two-stage (endogenous C consumption versus exogenous C priming) reciprocal transplant microcosm experiment to explore the effects of HFA on the decomposition of lower-quality..., ,