Changes in the amount and distribution of annual rainfall are expected to occur in the near future and may affect forest trees in
many ways including regeneration, growth and susceptibility to pests such as the pine wood nematode. Which will be the impact of
changes in precipitation regime, suggested by climate change scenarios, in maritime pine populations? In the present study we
intend to evaluate the impact of two precipitation scenarios, a wet and dry year by the standards of late 21st century, on distinct
Pinus pinaster populations from the three main genetic groups. Phenotypic plasticity of survival, growth, phenology, water use
efficiency and protein expression will be evaluated in these populations exposed to current and future precipitation regimes in a field
trial. These results will be complemented with the information on populations’ growth in source locations, inferred by
dendrochronology (tree-ring width and density). These time series will be used in regional climate model simulations, contributing to
project future changes in climate scenarios, and to estimate the impacts of climate change on the potential distribution of P. pinaster.
The main objective of this proposal is a better understanding of the impacts of predicted rainfall changes on maritime pine
populations. We hypothesize that:
- adaptive genetic variation is present among the main P. pinaster land races and in an altitudinal gradient
- phenotypic plasticity to climate change is reflected by survival, growth, phenology, d13C as a surrogate for water use efficiency,
differential protein expression and tree-ring width and density
- tree-ring parameters are related to climate signals and can be used in regional climate models for predictive purposes.
The specific objectives are:
1) to test if survival rate, growth rhythm, shoot phenology and WUE inferred through d13C, differ among distinct populations
exposed to different precipitation regimes imposed under open field conditions
2) to assess the impact of climatic parameters on tree-ring width and wood density components
3) to characterize protein profiles of three contrasting populations following imposition of different precipitation regimes under open
4) to integrate results and apply them in predictive regional climate models.
We expect to characterize the populations’ variability for adaptive traits, at the phenotypic and proteomic level, under specific
precipitation regimes; to estimate the potential distribution of P. pinaster under scenarios of climate change; and to contribute with
this information to management and conservation programmes and to the delimitation of seed collection areas.
Maria Isabel Lima Almeida Miranda Correia Esteves