Simulating forest productivity along a neotropical elevational transect: temperature variation and carbon use efficiency

Research output: Contribution to journalReview article

Abstract

A better understanding of the mechanisms controlling the magnitude and sign of carbon components in tropical forest ecosystems is important for reliable estimation of this important regional component of the global carbon cycle. We used the JULES vegetation model to simulate all components of the carbon balance at six sites along an Andes-Amazon transect across Peru and Brazil and compared the results to published field measurements. In the upper montane zone the model predicted a lack of forest vegetation, indicating a need for better parameterization of the responses of cloud forest vegetation within the model. In the lower montane and lowland zones simulated ecosystem productivity and respiration were predicted with reasonable accuracy, although not always within the error bounds of the observations. Model-predicted carbon use efficiency in this transect surprisingly did not increase with elevation, but remained close to the temperate value 0.5. Upper montane forests were predicted to allocate similar to 50% of carbon fixation to biomass maintenance and growth, despite available measurements showing that they only allocate similar to 33%. This may be explained by elevational changes in the balance between growth and maintenance respiration within the forest canopy, as controlled by both temperature- and pressure-mediated processes, which is not yet well represented in current vegetation models.

Details

Authors
  • Toby R. Marthews
  • Yadvinder Malhi
  • Cecile A. J. Girardin
  • Javier E. Silva Espejo
  • Luiz E. O. C. Aragao
  • Dan Metcalfe
  • Joshua M. Rapp
  • Lina M. Mercado
  • Rosie A. Fisher
  • David R. Galbraith
  • Joshua B. Fisher
  • Norma Salinas-Revilla
  • Andrew D. Friend
  • Natalia Restrepo-Coupe
  • Richard J. Williams
External organisations
  • External Organization - Unknown
Research areas and keywords

Subject classification (UKÄ) – MANDATORY

  • Physical Geography

Keywords

  • tropical forest production, JULES model, field measurements, maintenance, respiration, Peru, Brazil
Original languageEnglish
Pages (from-to)2882-2898
JournalGlobal Change Biology
Volume18
Issue number9
Publication statusPublished - 2012
Publication categoryResearch
Peer-reviewedYes
Externally publishedYes