UV radiation can strongly affect litter decomposition across broad climatic gradients, but the magnitude of its contribution differs among ecosystems. Current understanding of this process remains largely based on single‐species litter experiments, which overlook the compositional complexity of natural litter inputs and the potential role of litter mixing in modulating UV‐driven photodegradation. To address this gap, we conduc...

Litter decomposition is a critical biogeochemical process for carbon and nutrient cycling in terrestrial ecosystems. Ultraviolet (UV) radiation has been recognized to accelerate litter‐derived C release in arid and semi‐arid ecosystems; yet its spatial controls on determining the regional pattern of litter decomposition are poorly explored. Moreover, the limited understanding of how UV radiation interacts with traditional deco...