Sensitivity of river catchments to discharge-controlled dissolved carbon export: a study of eight catchments in southern Patagonia

Abstract Understanding the role of catchment sensitivity to dissolved carbon export aquatic systems is crucial predict future changes in fluxes under changing climatic conditions. We present 1-year variations organic (DOC) and inorganic (DIC) concentrations eight river catchments differing size (3–300 km 2 ), morphology (steep flat), vegetation cover (grassland, forest peatland) along a precipitation gradient southern Patagonia, Chile. The results show large differences between terms DOC (2–47 mg L −1 ; 1–44 tons −2 year ) DIC (0.1–38 1–5 response discharge. Small s teep hosting rich soils peatlands were most sensitive showed highest fastest release if evaluated on per unit area basis. Here, rain events caused rapid exponential increase release, while decreased exponentially. A negative correlation reveals minor importance production through mineralization catchments. Catchments had low discharged controlled attributed their high hydrological buffer capacity. Similarly, flat relatively dry Patagonian steppe have comparatively but short-term accumulated during periods. In conclusion, morphology, rather than or cover, was found major influence release.