Climate-Isotope Relationships in Trees

Variations in past climate are of interest because
they help explain and predict climate anomalies.
Independent, quantitative information regarding past
climate change is needed to place recently observed
changes and predictions for the future into a longer
perspective. Trees represent the best-dated archive
of climate information for the Holocene in Europe.
Climate reconstructions based on tree rings operate
under the assumption that the relationship between
climate and stable isotopic ratios in tree rings
remains stable over time. However, environmental
changes themselves may alter the sensitivity of this
relationship, causing time-dependent changes,
complicated by the fact that trees are living systems
that actively modify isotopic ratios during
incorporation of raw materials. Here we investigated
the long-term relationship between tree isotope
chronologies ( 13C and 18O), and climate, for trees
located at two ecologically non-extreme and
climatologically non-limiting sites. In addition, 18O in tree compartments was studied to help
understand the influence of intra-annual variations
in temperature and relative humidity on a tree ring
archive.

Autorentext

Presently employed at the Institute for Plant Sciences of the
University of Bern, Switzerland. Research interests: plant
physiological limitations under drought, global change, stable
isotopes.

Klappentext

Variations in past climate are of interest because
they help explain and predict climate anomalies.
Independent, quantitative information regarding past
climate change is needed to place recently observed
changes and predictions for the future into a longer
perspective. Trees represent the best-dated archive
of climate information for the Holocene in Europe.
Climate reconstructions based on tree rings operate
under the assumption that the relationship between
climate and stable isotopic ratios in tree rings
remains stable over time. However, environmental
changes themselves may alter the sensitivity of this
relationship, causing time-dependent changes,
complicated by the fact that trees are living systems
that actively modify isotopic ratios during
incorporation of raw materials. Here we investigated
the long-term relationship between tree isotope
chronologies (d13C and d18O), and climate, for trees
located at two ecologically non-extreme and
climatologically non-limiting sites. In addition,
d18O in tree compartments was studied to help
understand the influence of intra-annual variations
in temperature and relative humidity on a tree ring
archive.