Iranian trees may strengthen adaptation to climate change
Climate changes makes it harder for our trees to stay healthy, and the changing ice ages has also made diversity poorer. This is not the case in the major Caspian forests of Iran. Therefore, a new research project will investigate if trees planted in Denmark, but germinated from seed from the Caspian trees, can strengthen the Danish forests.
A total of about 15 ice ages combined with man’s exploitation and clearing for thousands of years has limited both species diversity and genetic diversity in European forests.
In the Caspian forests in northern Iran, the situation is quite different. Here are some 1.8 million ha of temperate deciduous forest of which 100- 200,000 ha are considered to be virgin forest. Ice ages and human activity have not affected these forests. Therefore, the forests houses species, gene pools and structures, which makes them a reference unparalleled for our forests, whether they are grown with production in mind, or whether content and biodiversity is the objective. They contain the same species - or very close relatives to our natural native species. Thus, the Caspian forests can be considered an ice age refuge for our species.
Previous attempts will pave the way
With a grant of 6 million DKK from VILLUM FONDEN a research project will now examine if trees originating in the Caspian forests are better than the Danish or European trees in adapting to changes in the climate or better at resisting diseases and insect pests. The project brings together researchers from IGN, University of Copenhagen and Research Institute of Forests and Rangelands (RifR) in Iran. Professor Palle Madsen, IGN is project manager.
"We know from experiments established in the 1930s with silver fir from up to 20 different origins in Europe that trees from areas that have not been affected by ice ages have a different and more robust gene pool. Trees from the southern silver fir origin derived from a small southern Italian ice age refuge in Calabria were far healthier and had growth that is more vigorous in the Danish trial than trees from all the other European origins, "says Palle Madsen.
"In the Caspian forests we find many species that are also native to us, for example beech, linden, maple, hornbeam, cherry, elm, yew and ash," continues Palle Madsen. In this new project, we will collect seeds from all of these tree species in Iran and Denmark. We will try to make them germinate in Danish nurseries and then plant them out in larger trials in Denmark. This will make it possible for us to compare their health and future growth with Danish species. We will work with our Iranian colleagues in choosing sites for collecting seeds and the construction of trials in both Iran and Denmark. Then we will investigate climate adaptation in both locations for some of the same tree species. In parallel with the construction of field trials, a series of DNA-based studies of the Iranian forest genetic diversity will be carried out. This may give us some faster indications of the genetic diversity in the Caspian forest trees compared to the European.
The project "The Caspian forests of Iran: A gene pool for the adaptation of European forests?" has just received a grant of 6.028.000 DKK from VILLUM FONDEN. The project will investigate if the provenances from the Caspian forests of Iran provides a greater genetic diversity, and if it leads to a better adaptability to climate changes than the populations of Danish or European tree species.
The project is a collaboration between the Department of Geosciences and Natural Resource (IGN) at Copenhagen University and the Research Institute of Forests and Rangelands (Rif R) in Tehran. From IGN professor Palle Madsen, Associate Professor Ole K. Hansen and Professor Jørgen Bo Larsen participate in the project, while Associate Professor Khosro Sagheb - Talebi from RifR leader of the Iranian group also participates. The project will run for five years.