Oecologia

, Volume 170, Issue 4, pp 1143–1154

Forest soil respiration reflects plant productivity across a temperature gradient in the Alps

  • Riccarda Caprez
  • Pascal A. Niklaus
  • Christian Körner
Ecosystem ecology - Original research

DOI: 10.1007/s00442-012-2371-3

Cite this article as:
Caprez, R., Niklaus, P.A. & Körner, C. Oecologia (2012) 170: 1143. doi:10.1007/s00442-012-2371-3

Abstract

Soil respiration (Rs) plays a key role in any consideration of ecosystem carbon (C) balance. Based on the well-known temperature response of respiration in plant tissue and microbes, Rs is often assumed to increase in a warmer climate. Yet, we assume that substrate availability (labile C input) is the dominant influence on Rs rather than temperature. We present an analysis of NPP components and concurrent Rs in temperate deciduous forests across an elevational gradient in Switzerland corresponding to a 6 K difference in mean annual temperature and a considerable difference in the length of the growing season (174 vs. 262 days). The sum of the short-lived NPP fractions (“canopy leaf litter,” “understory litter,” and “fine root litter”) did not differ across this thermal gradient (+6 % from cold to warm sites, n.s.), irrespective of the fact that estimated annual forest wood production was more than twice as high at low compared to high elevations (largely explained by the length of the growing season). Cumulative annual Rs did not differ significantly between elevations (836 ± 5 g C m−2 a−1 and 933 ± 40 g C m−2 a−1 at cold and warm sites, +12 %). Annual soil CO2 release thus largely reflected the input of labile C and not temperature, despite the fact that Rs showed the well-known short-term temperature response within each site. However, at any given temperature, Rs was lower at the warm sites (downregulation). These results caution against assuming strong positive effects of climatic warming on Rs, but support a close substrate relatedness of Rs.

Keywords

Soil CO2 effluxNPPElevationTemperate forestAcclimationTemperature sensitivity

Copyright information

© Springer-Verlag 2012

Authors and Affiliations

  • Riccarda Caprez
    • 1
  • Pascal A. Niklaus
    • 2
  • Christian Körner
    • 1
  1. 1.Institute of BotanyUniversity of BaselBaselSwitzerland
  2. 2.Institute of Evolutionary Biology and Environmental StudiesUniversity of ZürichZürichSwitzerland