Home-field advantage and ability alter labile and recalcitrant litter carbon decomposition in an alpine forest ecotone

Purpose Increasing evidence suggests that the role of home-field advantage (i.e. HFA, the specialized decomposers efficiently degrade native litter) in altering decomposition is not restricted to low- or high-quality litter, we thereby hypothesized that different litter carbon (C) fractions may respond differently to these specialized decomposers, blurring the universality of HFA. Additionally, the inherent functional ability of local soil decomposers (i.e. ability) can influence litter decomposition. Methods We determined how the decomposition of litter dissolved organic C (DOC), total phenolics, cellulose, and lignin responded to HFA and ability in an alpine forest ecotone (i.e. coniferous forest, alpine shrubland, and alpine meadow). Results HFA influenced labile C, cellulose, and lignin decomposition, and its magnitude and direction depended on initial litter traits, particularly positively with litter C, nitrogen, phosphorus, DOC, and total phenolics concentrations. The effect of ability on labile C loss decreased from forest to meadow, consistent with the functional breadth hypothesis, suggesting that a wider ability from recalcitrant forest litter environment can accelerate labile C loss. The effect of ability on lignin degradation increased from forest to meadow, suggesting that the shift in forest and shrub species to meadow can decelerate biotic lignin degradation. Conclusion The HFA occurrence is universal during decomposition, along with the distinct abilities were shaped by the altered plant compositions of mountain ecosystem, which has consequences for local plant-soil feedback by affecting litter decomposition.

Automated summary

The home-field advantage and the ability of local soil decomposers have significant impacts on litter decomposition, with different litter carbon fractions responding differently. This study provides insights into the importance of these factors in shaping decomposer communities and litter decomposition processes.