Soil microorganisms and plants are key players in the production and breakdown of organic matter, and together control global biogeochemical cycles of carbon, nitrogen and phosphorus. TER, the Division of Terrestrial Ecosystem Research, aims to advance our fundamental understanding of how plants and soil microorganisms respond to, and in turn shape, their abiotic and biotic environment, and to determine the consequences for the functioning of Earth’s ecosystems.

Research Mission

Primarily dedicated to basic research, TER addresses pressing environmental issues, such as the impact of climate and land-use change on ecosystem functioning and the role of soils in the global carbon cycle and in food security. In doing so, we work on scales from µm (i.e. the scale at which microbes operate) to the biosphere (i.e. where plant and microbial processes become evident), and in ecosystems spanning the Arctic tundra to tropical rainforests. We integrate this scale of thinking with state-of-the-art methods, including stable isotope tracing and biomarker fingerprinting, and are developing novel approaches to estimate gross environmental processes with isotope pool dilution techniques.

We are strongly committed to conduct world-leading research in a motivating and intellectually stimulating environment, and to train our students to become independent and internationally competitive scientists who enjoy research and contribute to society as conscientious citizens.

Uni Wien/Der Knopfdruecker

Research Projects

Tropical Biogeochemistry

Current Projects TER | Wolfgang Wanek

Tropical forests are centers of global biodiversity and integral parts of the global water and biogeochemical cycles. They play a key role in global climate control and terrestrial carbon sequestration, and are indispensable as reservoirs of terrestrial organic carbon and biodiversity. They continue to be reduced due to land use change and are impacted by climate and atmospheric change, with significant impacts on the diversity of species and the functional integrity of these ecosystems.

Pexels / Julia Volk

Tropical forests are highly heterogeneous in terms of prevailing climate, soils and disturbance status, with strong repercussions on their biogeochemical functioning. How they will respond to future global changes can to date only be studied by extrapolation from historical studies of ecosystem properties, forest structure, biomass and tree growth or from manipulative experiments. The lack of knowledge and of robust tropical forest data does not allow any conclusive interpolation of trends into the future. The available evidence nonetheless points to strong responses of tropical forests to global changes, most of them being negative in terms of carbon sequestration, nutrient cycling and biodiversity, indicating that they will rather feed forward on global warming and atmospheric change. Due to the extraordinarily high biodiversity and structural and biogeochemical heterogeneity of tropical forests, experimental manipulations in tropical forests simulating global changes are scarce or have not been undertaken at all. To study responses of tropical trees and ecosystems to past and current global changes we therefore rely on proxy studies such as isotopes in tree rings, long-term time series of net primary production across interannual variations in climate, large transect studies or meta-analyses synthesizing tropical forest responses across large gradients in climate and soil fertility. Our studies here rely on a suite of such approaches, ranging from reconstructions of tree growth and physiology using tree ring and herbarium analyses with stable isotope measurements, to long-term observations of the relation between forest productivity and climate, meta-analyses, large biodiversity – ecosystem function experiments in reforestation trials and to manipulative experiments with nutrient addition to advance our understanding of nutrient limitation to tropical forest functioning.

Key publications:

  • F. Hofhansl, J. Schnecker, G. Singer, W. Wanek (2015) New insights into mechanisms driving carbon allocation in tropical rainforests. New Phytologist 205: 137–146.
  • F. Hofhansl, J. Kobler, J. Ofner, S. Drage, EM. Pölz, W. Wanek (2014) Sensitivity of tropical forest aboveground productivity to climate anomalies in SW Costa Rica. Global Biogeochemical Cycles 28: 1437-1454.
  • PG. Taylor, GP. Asner, K. Dahlin, C. Anderson, DE. Knapp, RE. Martin, J. Mascaro, R. Chazdon, R. Cole, W. Wanek, F. Hofhansl, A. Townsend (2015) Landscape-scale controls on aboveground forest carbon stocks on the Osa Peninsula, Costa Rica. PlosONE 10(6): e0126748.
  • R.J.W. Brienen, P. Hietz, W. Wanek, M. Gloor (2013) Oxygen isotopes in tree rings record variation in precipitation d18O and amount effects in the south of Mexico. Journal of Geophysical Research – Biogeosciences 118: 1604-1615.
  • P. Hietz, B.L. Turner, W. Wanek, A. Richter, C.A. Nock, S.J. Wright (2011) Pervasive change in the nitrogen cycle in tropical forests. Science 334, 664-666.
  • C. Nock, P. Baker, W. Wanek, A. Leis, M. Grabner, S. Bunyavejchewin, P. Hietz (2011) Long-term increases in intrinsic water use efficiency do not lead to increased stem growth in a tropical monsoon forest in western Thailand. Global Change Biology 17, 1049-1063.

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