From microclimate to substrate control: Forest gap effects on fir twig litter decomposition and nutrient release diminish over a 12-year period - Aomiao Wu; Jingru Liu; Chengming You; Zhenfeng Xu; Han Li; Li Zhang; Lixia Wang; Bo Tan; Jordi Sardans; Josep Peñuelas (Forest Ecology and Management, 2026)