Jesús Julio Camarero Martínez, tenured scientist in the Instituto Pirenaico de Ecología (CSIC)
Jordi Voltas Velasco and Juan Pedro Ferrio Díaz, University of Lleida; and Patricia María Rodríguez González, University of Lisbon.
Instituto Pirenaico de Ecología (CSIC)
Riparian forests are simultaneously among the most dynamic and threatened communities in the Mediterranean basin, as a result not only of their secular degradation but also of their vulnerability to climate change.
It has been reasoned that a rise in temperatures will harm these riverside forests through its indirect effect on summertime water stress, altering the way the trees take up water through their roots and use it for their development.
In Mediterranean areas exposed to drought, riparian forests suffer a scarcity of water in summer when river flow also reduces. Although higher atmospheric concentrations of CO2 are boosting the water-use efficiency of trees, this does not automatically translate as greater growth and vigor, since drought can cause the decline of vulnerable forest species.
However, we still do not know how climate change (rising temperatures, extreme drought) and current fluvial dynamics (changes in water flow) are conditioning the effective availability of water in these forests. Our project will try to find this out through a detailed study of growth and water use in three well preserved woods on the River Ebro that are nevertheless also close to urban centers and accordingly at risk of degradation.
We will compare the description of the structure of the riparian ecosystem, the retrospective assessment of its tree growth (using dendrochronology) and an estimation of its water use (by reference to the natural abundance of stable isotopes like C, O and H).
Understanding the ecohydrological functioning of these forests will enable us to propose conservation measures that factor both climate change projections and future reductions in the water flow of major rivers like the Ebro.