Carbon flux and C, S isotopic characteristics of river waters from a karstic and a granitic terrain in the Yangtze River system

► Contrast chemical weathering processes in a karstic vs. granitic watershed. ► Reveal characteristics of δ13CDIC and δ34S of river waters in the two watersheds. ► Controls of DIC flux and CO2 consumption in the two watersheds were discussed. ► Intensive carbonate weathering affects carbon flux greatly in the Yangtze River Basin.