New method facilitates more precise climate reconstructions in temperate zone
09.09.2013 | Potsdam: Tree-rings of Pines are being investigated on the Telegrafenberg hill in Potsdam in order to reconstruct the climate of the past centuries. Until recently for climate reconstructions the so-called dendrochronology focused on the tree-rings only but now individual cells can be analysed. Potsdam scientist Ingo Heinrich has developed a new method at the GFZ German Research Centre for Geosciences which enables him to measure the cell sizes per tree ring, and not just the simple tree-ring widths. “The trees on the Telegrafenberg hill are our first test models, right at the front door of the GFZ”, says Heinrich, “We extract more detailed information than by applying the classical tree-ring method.”
The challenge: Worldwide tree rings have been used to reconstruct the climate of the past. However, such studies usually analysed the tree-ring widths of trees growing at extreme sites near the altitudinal and latitudinal tree lines. Long climate reconstructions on the basis of tree rings from the lowlands of the temperate zone are totally missing because such trees have not been found to be very climate sensitive yet. This is the challenge Ingo Heinrich and his team are focusing on. In a first pilot study making use of the new confocal laser scanning microscope technique at the GFZ the PhD student Wei Liang revealed that several cell parameters such as the average lumen area of the woody cells correlated well with the temperature. According to this, pines on the Telegrafenberg hill form large cells if the previous autumn and winter were warmer. Also important for an improved cell development are above-average amounts of precipitation in spring and summer.
In a next step the new method will be used to develop longer temperature reconstructions for North-Germany and Poland to finally facilitate statements about long-term temperature changes in our temperate zone.
Wei Liang, Ingo Heinrich, Sonia Simard, Gerhard Helle, Isabel Dorado Liñán, and Thilo Heinken (2013): “Climate signals derived from cell anatomy of Scots pine in NE Germany”, Tree Physiol. 33 (8): 833-844, doi:10.1093/treephys/tpt059