Woodlands in Europe: more tree species, more benefits
Forest homogenisation results in a lower ecosystem performance
Forest homogenisation results in a lower ecosystem performance. This summarises the findings of an international team of scientists from 29 institutions, including researchers from the University of Freiburg. The scientists were able to demonstrate that species-rich forest stands give rise to a higher number and more varied range of services than those with fewer species. 200 forests across six European countries were investigated as part of the study. The findings have now been published in the renowned scientific journal "PNAS" and “Nature Communications”.
Trees are service providers acting on behalf of mankind: they filter dust from the air, turn carbon dioxide into oxygen, protect the ground from erosion, help ensure the supply of drinking water and provide wood for construction and heating. Humans also use the forests for sport and recreation. However, the majority of European forests merely consist of one or just a handful of tree species. The team of researchers involved in the EU project "FunDivEurope – functional significance of forest biodiversity", coordinated by Professor Michael Scherer-Lorenzen from the Chair of Geobotany at the Faculty of Biology, was therefore tasked with investigating the correlation between local and regional biodiversity as well as ecosystem services, based on European forests of a range of climates.
One thing was clear: species-rich forests offer more services than those with fewer species. This means that forests which form part of stands made up of different species also give rise to a more varied range of services than homogenous forests. In their publication, the team of scientists highlight that a biodiversity deficit in European forests goes hand in hand with significant losses in services for nature and mankind. The lead author of the study, Dr Fons van der Plas from the Senckenberg Biodiversity and Climate Research Centre in Frankfurt (Main), summarised the findings of the work as follows: "One tree species is indeed able to provide individual services, for example high quality wood. However, a plethora of services – such as a habitat for birds, an attractive destination for tourists and a place in which to preserve water – can only be achieved by a diverse forest." This diversity, van der Plas went on, could very easily be increased. "In principle, it is not difficult to support natural seed dispersal and varied young growth, to plant additional species and to vary how species are put together in large woodlands, yet it is simply not done enough."
Transforming European forests into mixed stands would also pay off economically in the long term, adds Professor Jürgen Bauhus, from the Chair of Silviculture, Faculty of Environment and Natural Resources, as a diversity of tree species would also act as a kind of insurance against the increasing risks of global change, such as invasive pests and pathogens. It will also be important that mixed forest do also include economically attractive species for forestry, such as conifers. “The results also show that the development of forests in Germany is on the right track: the National Forest Inventory of Germany shows that our forests are continuously getting more diverse”, says Bauhus.
Publications:
van der Plas, F. et al. (2016). Biotic homogenization can decrease landscape-scale forest multifunctionality. In: Proceedings of the National Academy of Sciences. DOI: 10.1073/pnas.1517903113
van der Plas, F. et al. (2016). Jack-of-all-trades effects drive biodiversity-ecosystem multifunctionality relationships in European forests. In: Nature Communications. DOI: 10.1038/NCOMMS11109
Project „Funktionelle Bedeutung von Biodiversität in europäischen Wäldern“ (FunDivEUROPE)
The research leading to these results received funding from the European Union Seventh Framework Programme (FP7/2007-2013) under Grant Agreement 265171.
Contact:
Prof. Dr. Michael Scherer-Lorenzen
Geobotany, Institute for Biology II
Faculty of Biology
Albert Ludwig University of Freiburg
Tel: +49 (0)761 203 5014
e-mail: michael.scherer@biologie.uni-freiburg.de
or
Prof. Dr. Jürgen Bauhus
Institute of Forest Sciences
Albert Ludwig University of Freiburg
Tel.: +49 (0)761 203 3677
E-Mail: juergen.bauhus@waldbau.uni-freiburg.de
Print version of the press release (pdf).