Variations of stable carbon isotope imply sources of DIC in an alpine catchment - Meizhuang Zhu; Xingxing Kuang; Yuqing Feng; Enze Ma; Chunlin Song; Zhaoyong Hu; Xiaoyan Shi; Linfeng Fan; Fang Ji; Tian Zhao; Nima Ci Ren; Chunmiao Zheng (Journal of Hydrology, 2026)