The buffering of a riverine carbonate system under the input of acid mine drainage: Example from a small karst watershed, southwest China

In a karstic area affected by acid mine drainage (AMD), hydrochemical conditions, such as temperature, salinity, alkalinity, DIC, dissolved oxygen, and nutrients, may affect the buffering capacity of carbonate systems in freshwater systems. The resulting pH fluctuation is larger than that marine system. Therefore, this study focuses on riverine system under input AMD discusses variations series factors, including Revelle factor, γ DIC , Alk β ω . results revealed factor could reflect process effectively; addition, maximum value appeared at = 8.5. data points for greater indicated Huatan River had ability to absorb atmospheric CO 2 spring. Conversely, less reflected H + during degassing summer autumn. winter, were around value, indicating weakest capacity. As result, dynamics caused most sensitive response pH. did not always indicate reached equilibrium; presence strong was still possibility. Under acidic 2(aq) increased, absolute values increased correspondingly, enhanced degassing. four Representative Concentration Pathways scenarios (RCPs) included IPCC’s fifth assessment report, rate would decrease 5%, 15%, 26%, or 48%, depending scenario. Even though characteristics winter spring current it will eventually become sink concentration increases. light, carbon effect karst areas increasingly important.