Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Forests around the world affected by climate change

23.12.2014

Around the globe, forests are found to be undergoing strong changes due to human influence already today.

Degradation of woods due to man-made climate change cannot be ruled out for the future, a Special Feature in the Journal of Ecology, led by a team of scientists of the Potsdam Institute for Climate Impact Research (PIK), now shows. To understand and improve the resilience of forests, a combination of approaches from small-scale field experiments to large-scale computer simulations can help, according to the studies. Taking a risk perspective, the scientists caution that global warming puts additional pressure on some of the most valuable ecosystems on Earth.

"Forests are probably more at risk than previously thought,” says Christopher Reyer of PIK, coordinator of the Special Feature and lead-author of an overview article. “The observed changes affect forests as important as the Amazon, but also forests on all continents, possibly pushing some of them towards tipping points.”

Up to now, no example could be found where forests tipped into a state where no regrowth is possible due to man-made climate change. Yet the overview article identifies substantial research gaps. “This is hardly good news,” Reyer says. “It is in fact scary how little we still know about the resilience of forests, despite all the scientific progress we present in this special issue. From a risk perspective, climate change puts additional pressure on an exceptionally valuable ecosystem whose stability up to now cannot be properly assessed.”

**Forests preserve biodiversity, provide timber, store CO2**

Besides being home to a large part of the world’s plants and animals, hence preserving biodiversity, forests are also of great economic relevance. They provide timber in many countries, as well as game and fruit. “Some tropical forests, such as the Amazon, are also key for regional water cycles,” says Milena Holmgren of the University of Wageningen in the Netherlands. "How dense these forests are, affects the amount of rainfall that is recycled and also the amount of water that is retained. When forests become less dense, a smaller amount of water is recycled as rain and also less water is retained in the soil. Less dense forests facilitate also the growth of grass which burns easily in dry seasons. Fire can change the rules of the game drastically because grass burns easily and recovers fast whereas trees are very sensitive and need more time. So once a forest has been opened and starts burning, the end result can be a system that resembles a savanna with much grass and fewer trees. This changes the habitat for plants, animals and people.”

“The fate of forests is important also because they store huge amounts of the greenhouse gas CO2,” adds Holmgren. “Loosing forests and releasing carbon to the atmosphere contributes to climate warming and to the impacts we start to see in many regions of the world.”

**"Alleviating the negative effects of climate change on reforestation efforts" **

To assess the resilience of forests, long time scales are important. Over 2000 years, tropical peat swamp forests from Malaysian Borneo showed to be resilient even under disturbances such as fire or climate variability related to the El Niño weather phenomenon. Recent burning and agricultural expansion however clearly changed the landscape by replacing tropical peat swamp forests with open or even no forest. Still, things are not straightforward. Drought, on the other hand, is found to have variable effects on different tree species in different regions, and seasons, one of the new studies shows. In the end, it is a complex combination of stress factors that is likely to impact forests’ resilience.

In Finland and Australia, scientists performed field experiments on regrowth of forests. A joint dutch-finish team examined how boreal peat bogs can shift to forests and concluded that shrubs can pave the way for greener tree dominated landscapes in the far northern hemisphere. The Australian team studied the timing of seeding and the use of seedlings in restoring sites. “Adapted restoration practices could help alleviate the negative effects of climate change on reforestation efforts,” says Rachel Standish of The University of Western Australia. “We have some encouraging findings here. This is even more important as the area of disturbed forest ecosystems is clearly growing.”

Article: Reyer, C., Brouwers, N., Rammig, A., Brook, B., Epila, J., Grant, R.F., Holmgren, M., Langerwisch, F., Leuzinger, S., Lucht, W., Medlyn, B., Pfeiffer, M., Steinkamp, J., Vanderwel, M., Verbeeck, H., Villela, D. (2014): Forest resilience and tipping points at different spatio-temporal scales: approaches and challenges. Journal of Ecology (online) [DOI:10.1111/1365-2745.12337]

Article: Reyer, C., Rammig, A., Brouwers, N., Langerwisch, F. (2014): Forest resilience, tipping points and global change processes. Journal of Ecology (online) [DOI:10.1111/1365-2745.12342]

Article: Camarero, J.J., Gazol, A., Sangüesa-Barreda, G., Oliva, J., Vicente-Serrano, S.M. (2014): To die or not to die: early warnings of tree dieback in response to a severe drought. Journal of Ecology (online)

Article: Cole, L.E.S., Bhagwat, S.A., Willis, K.J. (2014): Long-term disturbance dynamics and resilience of tropical peat swamp forests. Journal of Ecology (online) [DOI:10.1111/1365-2745.12329]

Article: Holmgren, M., Lin, C.-Y., Murillo, J.E., Nieuwenhuis, A., Penninkhof, J., Sanders, N., van Bart, T., van Veen, H., Vasander, H., Vollebregt, M.E., Limpens, J. (2014): Positive shrub-tree interactions facilitate woody encroachment in boreal peatlands. Journal of Ecology (online)

Article: Jakovac, A.C.C., Peña-Claros, M., Kuyper, T.W., Bongers, F. (2014): Loss of secondary-forest resilience by land-use intensification in the Amazon. Journal of Ecology (online)

Article: Standish, R.J., Daws, M.I., Gove, A.D., Didham, R.K., Grigg, A.H., Koch, J.M., Hobbs, R.J. (2014): Long-term data suggest jarrah-forest establishment at restored mine sites is resistant to climate variability. Journal of Ecology (online)

Article: Steinkamp, J., Hickler, T. (2014): Is drought-induced forest dieback globally increasing? Journal of Ecology (online)

Weblink to the articles once they're published: http://www.journalofecology.org/view/0/specialfeatures.html

For further information please contact:
PIK press office
Phone: +49 331 288 25 07
E-Mail: press@pik-potsdam.de
Twitter: @PIK_Climate

Jonas Viering | Potsdam-Institut für Klimafolgenforschung
Further information:
http://www.pik-potsdam.de

More articles from Earth Sciences:

nachricht Climate satellite: Tracking methane with robust laser technology
22.06.2017 | Fraunhofer-Gesellschaft

nachricht How reliable are shells as climate archives?
21.06.2017 | Leibniz-Zentrum für Marine Tropenforschung (ZMT)

All articles from Earth Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Can we see monkeys from space? Emerging technologies to map biodiversity

An international team of scientists has proposed a new multi-disciplinary approach in which an array of new technologies will allow us to map biodiversity and the risks that wildlife is facing at the scale of whole landscapes. The findings are published in Nature Ecology and Evolution. This international research is led by the Kunming Institute of Zoology from China, University of East Anglia, University of Leicester and the Leibniz Institute for Zoo and Wildlife Research.

Using a combination of satellite and ground data, the team proposes that it is now possible to map biodiversity with an accuracy that has not been previously...

Im Focus: Climate satellite: Tracking methane with robust laser technology

Heatwaves in the Arctic, longer periods of vegetation in Europe, severe floods in West Africa – starting in 2021, scientists want to explore the emissions of the greenhouse gas methane with the German-French satellite MERLIN. This is made possible by a new robust laser system of the Fraunhofer Institute for Laser Technology ILT in Aachen, which achieves unprecedented measurement accuracy.

Methane is primarily the result of the decomposition of organic matter. The gas has a 25 times greater warming potential than carbon dioxide, but is not as...

Im Focus: How protons move through a fuel cell

Hydrogen is regarded as the energy source of the future: It is produced with solar power and can be used to generate heat and electricity in fuel cells. Empa researchers have now succeeded in decoding the movement of hydrogen ions in crystals – a key step towards more efficient energy conversion in the hydrogen industry of tomorrow.

As charge carriers, electrons and ions play the leading role in electrochemical energy storage devices and converters such as batteries and fuel cells. Proton...

Im Focus: A unique data centre for cosmological simulations

Scientists from the Excellence Cluster Universe at the Ludwig-Maximilians-Universität Munich have establised "Cosmowebportal", a unique data centre for cosmological simulations located at the Leibniz Supercomputing Centre (LRZ) of the Bavarian Academy of Sciences. The complete results of a series of large hydrodynamical cosmological simulations are available, with data volumes typically exceeding several hundred terabytes. Scientists worldwide can interactively explore these complex simulations via a web interface and directly access the results.

With current telescopes, scientists can observe our Universe’s galaxies and galaxy clusters and their distribution along an invisible cosmic web. From the...

Im Focus: Scientists develop molecular thermometer for contactless measurement using infrared light

Temperature measurements possible even on the smallest scale / Molecular ruby for use in material sciences, biology, and medicine

Chemists at Johannes Gutenberg University Mainz (JGU) in cooperation with researchers of the German Federal Institute for Materials Research and Testing (BAM)...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Plants are networkers

19.06.2017 | Event News

Digital Survival Training for Executives

13.06.2017 | Event News

Global Learning Council Summit 2017

13.06.2017 | Event News

 
Latest News

Quantum thermometer or optical refrigerator?

23.06.2017 | Physics and Astronomy

A 100-year-old physics problem has been solved at EPFL

23.06.2017 | Physics and Astronomy

Equipping form with function

23.06.2017 | Information Technology

VideoLinks
B2B-VideoLinks
More VideoLinks >>>