The project investigates how global warming affects forest soil processes. A special focus lies on soil carbon. Forest soil store huge amounts of organic carbon which could be released into the atmosphere.
Decomposer microbes mineralize dead organic matter such as leave and root litter and thereby release important nutrients for plant growth. A share of the taken-up organic carbon is used as microbial energy source and CO2 is respired. This results in a considerable CO2 efflux from the forest soil surface to the atmosphere, which is called “(heterotrophic) soil respiration”.
The activity of decomposer microbes critically depends on the soil temperature. Warmer soil increases the microbial activity, the decomposition rates, and the soil CO2 efflux. Therefore, global warming could eventually result in a soil carbon loss to the atmosphere.
In order to simulate a potential global warming scenario, we installed heating cables in a forest soil close to the village of Achenkirch/Northern Limestone Alps/Tyrol and warmed the soil by 4 °C since spring 2005. The soil CO2 efflux increased by approximately 40 % due to the simulated warming and the effect still sustains. Accordingly our results suggest that warming could result in a substantial soil carbon loss in this forest ecosystem.
A series of experiments were conducted to assess the warming effects on different soil CO2 efflux sources, effects on tree roots, effects on various soil organic matter fractions and effects on the microbial community structure and function (references below). Currently, the international collaboration project is funded by the FWF (I-3745) and DFG. For more detailed information on the project goals and collaborators please visit the project webpage at research gate.
Project relevant publications:
Schindlbacher, A., Beck, K., Holzheu, S., & Borken, W. (2019). Inorganic carbon leaching from a warmed and irrigated carbonate forest soil. Frontiers in Forests and Global Change, 2, 40. https://doi.org/10.3389/ffgc.2019.00040
Parts, K., Tedersoo, L., Schindlbacher, A., Sigurdsson, B.D., Leblans, N.I.W., Oddsdóttir, E.S., et al. (2018). Acclimation of fine root systems to soil warming: Comparison of an experimental setup and a natural soil temperature gradient. Ecosystems. https://doi.org/10.1007/s10021-018-0280-y
Liu, D., Keiblinger, K.M., Schindlbacher, A., Wegner, U., Sun, H., Fuchs, S., Lassek, C., Riedel, K., Zechmeister-Boltenstern S (2017) Microbial functionality as affected by experimental warming of a temperate mountain forest soil – A metaproteomics survey. Applied Soil Ecology 117: 196-202, https://doi.org/10.1016/j.apsoil.2017.04.021
Schnecker, J., Borken, W., Schindlbacher, A., and Wanek, W., (2016) Little effects on soil organic matter chemistry of density fractions after seven years of forest soil warming. Soil Biol. Biochem. 103, 300-307, https://doi.org/10.1016/j.soilbio.2016.09.003.
Schindlbacher, A., Schnecker, J., Takriti, M., Borken, W., Wanek, W. (2015) Microbial physiology and soil CO2 efflux after 9 years of soil warming in a temperate forest – no indications for thermal adaptations. Global Change Biology 21: 4265-4277, https://doi.org/10.1111/gcb.12996.
Schindlbacher, A., Borken, W., Djukic, I., Brandstätter, C., Spötl, C., Wanek, W. (2015) Contribution of carbonate weathering to the CO2 efflux from temperate forest soils. Biogeochemistry, 124, 273-290. https://doi.org/10.1007/s10533-015-0097-0.
Schindlbacher, A., Jandl, R., Schindlbacher S. (2014) Natural variations in snow cover do not affect the annual soil CO2 efflux from a mid-elevation temperate forest, Global Change Biology, 20, 622-632, https://doi.org/10.1111/gcb.12367.
Schindlbacher, A., Wunderlich, S., Borken, W., Kitzler, B., Zechmeister-Boltenstern, B., Jandl, R. (2012) Soil respiration under climate change: prolonged summer drought offsets soil warming effects, Global Change Biology,18, 2270–2279, https://doi.org/10.1111/j.1365-2486.2012.02696.x.
Kuffner, M., Hai, B., Rattei, T., Melodelima, C., Schloter, M., Zechmeister-Boltenstern, S., Jandl, R., Schindlbacher, A., Sessitsch, A. (2012) Effects of season and experimental warming on the bacterial community in a temperate mountain forest soil assessed by 16S rRNA gene pyrosequencing, FEMS Microbial Ecology, 82, 551-562, https://doi.org/10.1111/j.1574-6941.2012.01420.x.
Schindlbacher, A., Rodler, A., Kuffner, M., Kitzler, B., Sessitsch, A., Zechmeister-Boltenstern, S. (2011) Experimental warming effects on the microbial community of a temperate mountain forest soil, Soil Biology & Biochemistry, 43, 1417-1425, https://doi.org/10.1016/j.soilbio.2011.03.005.
Díaz-Pinés, E., Schindlbacher, A., Pfeffer, M., Jandl, R., Zechmeister-Boltenstern S., Rubio, A. (2010) Root trenching – A useful tool to estimate autotrophic soil respiration? Case study in an Austrian mountain forest. European Journal of Forest Research, 129, 101-109.
Schindlbacher, A., Zechmeister-Boltenstern, S., Jandl, R. (2009): Carbon losses due to soil warming: Do autotrophic and heterotrophic soil respiration respond equally? Global Change Biology, 15, 901-913.
Schindlbacher, A., Zechmeister-Boltenstern, S., Kitzler, B., Jandl, R. (2008): Experimental forest soil warming: response of heterotrophic and autotrophic soil respiration to a short-term 10°C temperature rise. Plant and Soil, 303, 323-330.
Schindlbacher, A., Zechmeister-Boltenstern, S., Glatzel, G., Jandl, R. (2007): Winter soil respiration from an Austrian mountain forest. Agriculture and Forest Meteorology, 146, 205-215.