Abstract

Increasing temperatures and changes in the intensity and frequency of precipitations may impact the ability of tropical high-elevation Andean ecosystems (Páramos) to store and retain carbon (C). We, therefore, examined how warming and fluctuations in soil moisture could influence soil CO₂ emissions from heterotrophic respiration (R_H, the result of microbial respiration), of two Páramos of contrasting climatic regimes within their area of distribution. We here show high sensitivity of both R_H and Q₁₀ under warmer and fluctuating moisture conditions. Together with the high rates of C-normalized R_H compared to other soil C-rich ecosystems from higher latitudes (2 μmol gC⁻¹ h⁻¹ versus 0,4 μmol gC⁻¹ h⁻¹, respectively) our results evidenced how soil heterotrophic-derived CO₂ emissions could potentially increase under expected climate scenarios, eventually altering the capacity of soil Páramos to sequester C.