EGU General Assembly 2021
© Author(s) 2021. This work is distributed under
the Creative Commons Attribution 4.0 License.

Warming effects on soil CO2 efflux in the tropical Andes: Insights from an experimental thermosequence with dominant tree species.

Elizabeth Ocampo Montoya1, Andrew T. Nottingham2, Juan Camilo Villegas Palacio3, Lina M. Mercado4, Zorayda Restrepo5, and Patrick Meir6
Elizabeth Ocampo Montoya et al.
  • 1Facultad de Ingeniería, Universidad de Antioquia, Medellín, Colombia (
  • 2School of Geography, University of Leeds, Leeds, United Kingdom (
  • 3Facultad de Ingeniería, Universidad de Antioquia, Medellín, Colombia (
  • 4College of Life and Environmental Sciences, University of Exeter, Exeter, United Kingdom (
  • 5Facultad de Ingeniería, Universidad de Antioquia, Medellín, Colombia (
  • 6Australian National University, Canberra, Australia (

Tropical forests, while only occupying 12% to 15% of the Earth's surface, contain about 25% of the world's carbon biomass, with soils representing the second largest reservoir. Yet, recent studies have suggested that, in response to changing environmental conditions, in future decades tropical forests can switch from carbon sinks to carbon sources, with profound implications for the global carbon cycle. Most of these conclusions result from studies in lowland humid forests. However, other tropical forests, such as those occurring in the Andes are also important determinants of regional-to-global biogeochemical functioning, and their sensitivity to future warming has been less studied than in lowland forests. In this study, we explore intra and interspecific thermal sensitivity of soil respiration and its components (autotrophic and heterotrophic) in 15 dominant tree species in the tropical Andes, through an experimental thermosecuence in the Colombian Andes that uses elevation as a proxy for warming. In this thermosequence, a common garden experiment was set up and individuals from 15 dominant species were planted in three sites that represent a temperature gradient: the higher elevation site (2452 masl) corresponds to the base condition; the mid-elevation site (1326 masl) represents a warming of 8°C; and the lower site (575 masl) and it represents a warming of 12°C. Our results indicate consistently higher respiration values with increased temperature both within and between tree species. We used 𝑸10 values (the factor by which soil respiration increases for every 10-degree rise in temperature) to determine the temperature sensitivity of soil respiration. More specifically, for a warming of 5°C there is a temperature coefficient of 𝑸10 = 2 and for a warming of 9°C and there is a temperature coefficient 𝑸10 = 3, this means that for the greater increase temperature the soil respiration can increase faster. Notably, our results show that not all species respond equally to augmented temperatures, highlighting the potential for differential effects of increased temperature and more generally, of environmental change in the compositions and function of these strategic ecosystems. Collectively, our results are relevant for the management and adaptation of ecosystems, particularly tropical Andean forest, and for the refinement of ecological models that support projections of global environmental change and carbon cycle. 

How to cite: Ocampo Montoya, E., Nottingham, A. T., Villegas Palacio, J. C., Mercado, L. M., Restrepo, Z., and Meir, P.: Warming effects on soil CO2 efflux in the tropical Andes: Insights from an experimental thermosequence with dominant tree species., EGU General Assembly 2021, online, 19–30 Apr 2021, EGU21-13864,, 2021.