Fig. 2: Strong elevation gradients of pCO2, CH4 and %N2O in the Andean headwater and piedmont streams.

Variations of the partial pressure of CO2 (pCO2), CH4 dissolved concentration, N2O saturation level (%N2O), and oxygen saturation level (%O2) in the Napo streams as a function of elevation (a, e, i, m), catchment slope (b, f, j, n), forest cover (c, g, k, o), and water temperature (d, h, l, p). Symbols show the median and error bars the interquartile range, stations in the main-stem are shown by blue circles and in the tributaries by green squares, and black lines indicate linear or exponential fits to the data. Solid lines show fits to the data (Supplementary Table 4).