Water vapor- and CO2 budgets of woods
Increased atmospheric CO2 concentrations have already caused large-scale physiological responses of European forests. In particular, the efficiency of water-use of trees, which is coupled to the uptake of CO2 during photosynthesis of leaves and needles has changed significantly. According to the study of a large, interdisciplinary team of researchers, European broadleaf and coniferous trees have increased their water-use efficiency since the beginning of the 20th century by 14% and 22%, respectively.
During photosynthesis trees take up carbon dioxide (CO2) from the air. In return they loose water vapor (H2O) through tiny pores of their leaves or needles, so-called stomata.
This gas exchange between trees and the atmosphere is regulated through the opening widths (aperture) of their stomata. Wider apertures of the stomata allow the uptake of higher numbers of CO2 molecules, but promote an increased loss of water vapor (transpiration) into the atmosphere. The opposite holds for narrowed stomatal apertures.
“Assuming that the trees demand for CO2 does not change, they can reduce the aperture of the stomates of their leaves and needles under increasing atmospheric CO2 concentrations.
This should lower the rates of transpiration and minimize the tree’s water loss”, says Gerhard Helle at the GFZ German Research Centre for Geosciences, co-author of the study. “Nevertheless, a 5% increase in European forest transpiration was calculated over the twentieth century. This can likely be attributed to a lengthened growing season, increased transpiration due to a warmer environment, and an enhanced leaf area.”
The results are important for better estimates of the impact of forests on climate, improved model scenarios of future climate development and more reliable assessment of the global water cycle.
Furthermore, ecological consequences might evolve because of the significantly different responses to increased atmospheric CO2 of broadleaf and needleleafed species.
The data set utilized in this study has been established from a tree-ring based network (ISONET) funded by the EU that aims at the analysis of carbon isotope ratios (13C/12C). ISONET was initiated and coordinated by GFZ-scientists Gerhard H. Schleser (presently also FZ-Jülich) and Gerhard Helle.
D. C. Frank et al.,: „Water-use effciency and transpiration across European forests during the Anthropocene”, NATURE CLIMATE CHANGE, VOL. 5, MAY 2015, DOI: 10.1038/NCLIMATE2614
Franz Ossing | Helmholtz-Zentrum Potsdam - Deutsches GeoForschungsZentrum GFZ
Stagnation in the South Pacific Explains Natural CO2 Fluctuations
23.02.2018 | Carl von Ossietzky-Universität Oldenburg
First evidence of surprising ocean warming around Galápagos corals
22.02.2018 | University of Arizona
A newly developed laser technology has enabled physicists in the Laboratory for Attosecond Physics (jointly run by LMU Munich and the Max Planck Institute of Quantum Optics) to generate attosecond bursts of high-energy photons of unprecedented intensity. This has made it possible to observe the interaction of multiple photons in a single such pulse with electrons in the inner orbital shell of an atom.
In order to observe the ultrafast electron motion in the inner shells of atoms with short light pulses, the pulses must not only be ultrashort, but very...
A group of researchers led by Andrea Cavalleri at the Max Planck Institute for Structure and Dynamics of Matter (MPSD) in Hamburg has demonstrated a new method enabling precise measurements of the interatomic forces that hold crystalline solids together. The paper Probing the Interatomic Potential of Solids by Strong-Field Nonlinear Phononics, published online in Nature, explains how a terahertz-frequency laser pulse can drive very large deformations of the crystal.
By measuring the highly unusual atomic trajectories under extreme electromagnetic transients, the MPSD group could reconstruct how rigid the atomic bonds are...
Quantum computers may one day solve algorithmic problems which even the biggest supercomputers today can’t manage. But how do you test a quantum computer to...
For the first time, a team of researchers at the Max-Planck Institute (MPI) for Polymer Research in Mainz, Germany, has succeeded in making an integrated circuit (IC) from just a monolayer of a semiconducting polymer via a bottom-up, self-assembly approach.
In the self-assembly process, the semiconducting polymer arranges itself into an ordered monolayer in a transistor. The transistors are binary switches used...
Breakthrough provides a new concept of the design of molecular motors, sensors and electricity generators at nanoscale
Researchers from the Institute of Organic Chemistry and Biochemistry of the CAS (IOCB Prague), Institute of Physics of the CAS (IP CAS) and Palacký University...
15.02.2018 | Event News
13.02.2018 | Event News
12.02.2018 | Event News
23.02.2018 | Physics and Astronomy
23.02.2018 | Health and Medicine
23.02.2018 | Physics and Astronomy