Causes of variation in mineral soil C content and turnover in differently managed beech dominated forests
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Background and aims
Forest soils are important carbon stores and considered as net CO2 sinks over decadal to centennial time scales. Intensive forest management is thought to reduce the carbon sequestration potential of forest soils. Here we study the effects of decades of forest management (as unmanaged forest, forest under selection cutting, forest under age class management) on the turnover of mineral associated soil organic matter (MOM) in German beech (Fagus sylvatica L.) dominated forests.
Radiocarbon contents were determined by accelerator mass spectrometry (AMS) in 79 Ah horizon MOM fractions of Cambisols (n = 13), Luvisols (n = 51) and Stagnosols (n = 15). Mean residence times (MRTs) for soil organic carbon (SOC) were estimated with a 2-pool model using the litter input derived from a forest inventory.
MOM fractions from Ah horizons contained 64 ± 8.8 % of the bulk SOC. The radiocarbon content of MOM fractions in Ah horizons, expressed as Δ14C, ranged between −2.8 ‰ and 114 ‰ for the three soil groups. Almost all samples contained a detectable proportion of ‘bomb’ carbon fixed from the atmosphere since 1963. Under the assumption that depending on the soil texture between 19 % and 24 % of the SOC from the labile pool is transferred to the stable SOC pool, the corresponding MRTs ranged between 72 and 723 years, with a median of 164 years.
Our results indicate that the MOM fraction of Ah horizons from beech forests contained a high proportion of young carbon, but we did not find a significant decadal effect of forest management on the radiocarbon signature and related turnover times. Instead, both variables were controlled by clay contents and associated SOC concentrations (p < 0.01). This underlines the importance of pedogenic properties for SOC turnover in the MOM fraction.
KeywordsForest management Carbon sequestration Radiocarbon (14C) dating Density fractionation Soil organic matter stabilization Mineral associated organic matter
We thank Susan E. Trumbore and the reviewers for their helpful comments on a earlier version of the manuscript. We also thank Kathrin Henkel and Knut Mehler for help with the soil sampling and Claudia Seilwinder for help with the forest inventories. Iris Kuhlmann, Sarah Walter and Nils Reinhardt are acknowledged for the help with the physical fractionation of soil samples, Ines Hilke and Birgit Fröhlich for the CN analysis and Axel Steinhof for the radiocarbon analysis. We are grateful to Sonja Gockel and Simone Pfeiffer for their work in maintaining the plot and project infrastructure in the Hainich. The work has been funded by the DFG Priority Program 1374 “Infrastructure-Biodiversity-Exploratories” and the Max-Planck-Society. Markus Fischer, Elisabeth Kalko, Eduard Linsenmair, Jens Nieschulze, Daniel Prati, François Buscot are acknowledged for their contribution in setting up the Biodiversity Exploratories project. Field work permits were issued by the responsible state environmental offices of Thüringen (according to § 72 BbgNatSchG).
- Baisden WT, Amundson R, Cook AC, Brenner DL (2002) Turnover and storage of C and N in five density fractions from California annual grassland surface soils—art. no. 1117. Global Biogeochem Cycles 16:1117–1117Google Scholar
- Castanha C, Trumbore S, Amundson R (2008) Methods of separating soil carbon pools affect the chemistry and turnover time of isolated fractions. Radiocarbon 50:83–97Google Scholar
- Coleman K, Jenkinson DS (2008) RothC 26.3: A model for the turnover of carbon in soil. Model description and windows user guide. Rothamsted Research, Herpender Herts, UK. Available at http://www.rothamsted.bbsrc.ac.uk/aen/carbon/mod26_3_win.pdf. Accessed 26 Feb 2013
- FAO (2006) Guidelines for profile description, 4th edn. FAO, RomeGoogle Scholar
- Fischer M, Bossdorf O, Gockel S, Hansel F, Hemp A, Hessenmöller D, Korte G, Nieschulze J, Pfeiffer S, Prati D, Renner S, Schöning I, Schumacher U, Wells K, Buscot F, Kalko EKV, Linsenmair KE, Schulze ED, Weisser WW (2010) Implementing large-scale and long-term functional biodiversity research: The Biodiversity Exploratories. Basic Appl Ecol 11:473–485CrossRefGoogle Scholar
- Gömöryová E (2004) Small-scale variation of microbial activities in a forest soil under beech (Fagus Sylvatica L.) stand. Pol J Ecol 52:311–321Google Scholar
- Harrison AF, Harkness DD, Rowland AP, Garnett JS, Bacon PJ (2000) Annual carbon and nitrogen fluxes in soils along the European forest transect, determined using 14C-bomb. In: Schulze E-D (ed) Carbon and nitrogen cycling in European forest ecosystems. Ecological Studies 142. Springer, Berlin Heidelberg, pp 237–256CrossRefGoogle Scholar
- IUSS-Working-Group-WRB (2006) World reference base for soil resources 2006, vol 103. World Soil Reports, 2nd edn. FAO, RomeGoogle Scholar
- Köble R, Seufert G (2001) Novel maps for forest tree species in Europe. In: Proceedings conference on a changing atmosphere, 8th European symposium on the physico-chemical behaviour of atmospheric pollutants, 17–20 September 2001, Torino.Google Scholar
- Levin I, Kromer B (2004) The tropospheric (CO2)-C-14 level in mid-latitudes of the Northern Hemisphere (1959–2003). Radiocarbon 46:1261–1272Google Scholar
- Mund M (2004) Carbon pools of European beech forests (Fagus sylvatica) under different silvicultural management. Berichte des Forschungszentrums Waldökosysteme. Reihe A – Band 189. Forschungszentrum Waldökosysteme, GöttingenGoogle Scholar
- R-Development-Core-Team (2012) R: A language and environment for statistical computing. R Foundation for Statistical Computing, ViennaGoogle Scholar
- Schober R (1972) Die Rotbuche. Verlag J.D. Sauerländer, Frankfurt a.MGoogle Scholar
- Soetaert K, Petzoldt T (2010) Inverse modelling, sensitivity and Monte Carlo analysis in R using package FME. J Stat Softw 33:1–28Google Scholar
- Steinhof A, Adamiec G, Gleixner G, van Klinken GJ, Wagner T (2004) The new C-14 analysis laboratory in Jena, Germany. Radiocarbon 46:51–58Google Scholar
- Wäldchen J, Schulze ED, Mund M, Winkler B (2011) Der Einfluss politischer, rechtlicher und wirtschaftlicher Rahmenbedingungen des 19. Jahrhunderts auf die Bewirtschaftung der Wälder im Hainich-Dün-Gebiet (Nordthüringen). Forstarchiv 82:35–47Google Scholar
- Wirth C, Schulze ED, Schwalbe G, Tomczyk S, Weber G, Weller E (2004) Dynamik der Kohlenstoffvorräte in den Wäldern Thüringens. Mitteilungen 23/2004. Thüringer Landesanstalt für Wald, Jagd und Fischerei, GothaGoogle Scholar