Autotrophic and heterotrophic soil respiration in a Norway spruce forest: estimating the root decomposition and soil moisture effects in a trenching experiment
- 667 Downloads
The two components of soil respiration, autotrophic respiration (from roots, mycorrhizal hyphae and associated microbes) and heterotrophic respiration (from decomposers), was separated in a root trenching experiment in a Norway spruce forest. In June 2003, cylinders (29.7 cm diameter) were inserted to 50 cm soil depth and respiration was measured both outside (control) and inside the trenched areas. The potential problems associated with the trenching treatment, increased decomposition of roots and ectomycorrhizal mycelia and changed soil moisture conditions, were handled by empirical modelling. The model was calibrated with respiration, moisture and temperature data of 2004 from the trenched plots as a training set. We estimate that over the first 5 months after the trenching, 45% of respiration from the trenched plots was an artefact of the treatment. Of this, 29% was a water difference effect and 16% resulted from root and mycelia decomposition. Autotrophic and heterotrophic respiration contributed to about 50% each of total soil respiration in the control plots averaged over the two growing seasons. We show that the potential problems with the trenching, decomposing roots and mycelia and soil moisture effects, can be handled by a modelling approach, which is an alternative to the sequential root harvesting technique.
KeywordsSoil moisture Picea abies PLS Root respiration Root decomposition Soil temperature
This study was financially supported by the Swedish National Energy Administration (STEM), the Swedish Environmental Protection Agency (SNV), the Swedish Research council (VR), the Swedish Research council for Environment, Agricultural Sciences and Spatial Planning (Formas) and by the Swedish Research Council for Forestry and Agriculture. We thank Anders Holm for practical assistance.
- Betson NR, Göttlicher SG, Hall M, Wallin G, Richter A, Högberg P (2007) No diurnal variation in rate or carbon isotope composition of soil respiration in a boreal forest. Tree Physiol 27:749–756Google Scholar
- Comstedt D (2008) Explaining temporal variations in soil respiration rates and δ13C in coniferous forest ecosystems. Doctoral thesis, Örebro University (manuscript #3 in thesis)Google Scholar
- Epron D, le Dantec V, Dufrene E, Granier A (2001) Seasonal dynamics of soil carbon dioxide efflux and simulated rhizosphere respiration in a beech forest. Tree Physiol 21:145–152Google Scholar
- Högberg P, Nordgren A, Högberg MN, Ottosson-Löfvenius M, Bhupinderpal-Singh, Olsson P, Linder S (2005) Fractional contributions by autotrophic and heterotrophic respiration to soil-surface CO2 efflux in Boreal forests. In: Griffiths H, Jarvis PG (eds) The carbon balance of forest biomes. Taylor & Francis, Oxford, pp 251–267Google Scholar
- James FC, McCulloch CE (1990) Multivariate analysis in ecology and systematics: Panacea or Pandora’s box? Annu Rev Ecol Syst 21:129–166Google Scholar
- Kuzyakov Y, Gavrichkova O (2010) Time lag between photosynthesis and CO2 efflux from soil: a review. Glob Change Biol (in press)Google Scholar
- Lavigne MB, Ryan MG, Anderson DE, Baldocchi DD, Crill PM, Fitzjarrald DR, Goulden ML, Gower ST, Massheder JMM, McCaughey JH, Rayment MB, Striegl RG (1997) Comparing nocturnal eddy covariance measurements to estimates of ecosystem respiration made by scaling chamber measurements at six coniferous boreal sites. J Geophys Res 102:28977–28985CrossRefGoogle Scholar
- Pritchard SG, Strand AE, McCormack ML, Davis MA, Oren R (2008) Mycorrhizal and rhizomorph dynamics in a loblolly pine forest during 5 years of free-air-CO2-enrichment. Glob Change Biol 14:1–13Google Scholar
- Rustad LE, Campbell JL, Marion GM, Norby RJ, Mitchell MJ, Hartley AE, Cornelissen JHC, Gurevitch J, GCTE-NEWS (2001) A meta-analysis of the response of soil respiration, net nitrogen mineralization, and aboveground plant growth to experimental ecosystem warming. Oecologia 126:543–562CrossRefGoogle Scholar
- Silver WL, Miya RK (2001) Global patterns in root decomposition: comparisons of climate and litter quality effects. Oecologia 129:407–419Google Scholar