Understanding the role of catchment sensitivity to dissolved carbon export to aquatic systems is crucial to predict future changes in carbon fluxes under changing climatic conditions. We present 1-year variations in dissolved organic (DOC) and inorganic carbon (DIC) concentrations and fluxes in eight river catchments differing in size (3–300 km²), morphology (steep to flat), and vegetation cover (grassland, forest and peatland) along a precipitation gradient in southern Patagonia, Chile. The results show large differences between catchments in terms of river DOC (2–47 mg L⁻¹; 1–44 tons km⁻² year⁻¹) and DIC (0.1–38 mg L⁻¹; 1–5 tons km⁻² year⁻¹) concentrations and fluxes in response to changes in discharge. Small and steep catchments hosting organic rich forest soils and peatlands were the most sensitive and showed the highest and fastest DOC release if evaluated on a per unit area basis. Here, rain events caused a rapid exponential increase in DOC release, while DIC export decreased exponentially. A negative correlation between DOC and DIC reveals the minor importance of DIC production through mineralization of DOC in most catchments. Catchments hosting large peatlands had low sensitivity to discharged controlled DOC release attributed to their high hydrological buffer capacity. Similarly, flat and relatively dry Patagonian steppe catchments have comparatively low sensitivity but have short-term high release of DOC accumulated during dry periods. In conclusion, morphology, rather than catchment size or vegetation cover, was found to show the major influence on sensitivity to DOC release.

了解流域敏感性对向水生系统输出溶解碳的作用对于预测气候条件变化下碳通量的未来变化至关重要。我们展示了 8 个不同大小（3-300 km ²）、形态（陡峭到平坦）和植被覆盖（草地、森林和泥炭地）沿着智利巴塔哥尼亚南部的降水梯度。^{结果表明，在河流 DOC（2-47 mg L -1}；1-44 吨 km ^-2 年^-1）和 DIC（0.1-38 mg L ^-1；1-5 吨 km ^-2 ）方面，集水区之间存在很大差异 年^-1) 浓度和通量响应排放的变化。小号_如果以单位面积为基础进行评估，拥有丰富有机森林土壤和泥炭地的陡峭集水区是最敏感的，并且显示出最高和最快的 DOC 释放。在这里，降雨事件导致 DOC 释放呈指数级增长，而 DIC 输出呈指数级下降。DOC 和 DIC 之间的负相关表明，在大多数流域中通过 DOC 矿化产生 DIC 的重要性较小。拥有大型泥炭地的流域对排放的受控 DOC 释放的敏感性较低，这归因于它们的高水文缓冲能力。类似地，平坦且相对干燥的巴塔哥尼亚草原集水区的敏感性相对较低，但在干旱期间累积的 DOC 短期高释放。总之，形态，而不是集水区大小或植被覆盖，