Water consumption and carbon capture by trees of an evergreen and a deciduous mountain forest as functional indicators of slow environmental changes in South Ecuador
DFG Projekt Be 473/42-1
From 06/2013 to 04/2019Principal Investigator: Erwin Beck
Staff: Simone Strobl
This transfer project contributes to the development of a multifactorial indicator prototype for global change effects. It uses water and carbon relations of trees as primary functional indicators of subtle environmental changes which cannot be directly observed.
Acquisition of carbon by a tree and its concomitant water loss by transpiration is coupled as water use efficiency (WUE), which as a parameter integrating two ecophysiological processes should display a high sensitivity to ambiental conditions. The project is based on a new model allowing computation of the entire crown. Parameterization of the model is by data of leaf gas exchange, total water loss, and structural data of the crown. Total water consumption will be determined either by stem flow monitoring or by the D2O injection method. Net carbon gain by the entire crown can be calculated from a crown-specific WUE. Project C5 measures WUE and related parameters of single trees which according to their functional type exhibit different sensitivity (of WUE) to ambiental changes. Fast growing pioneers may turn out as particularly useful indicators. The described measurements will be supplemented by data on stem growth, phenology (longevity of leaves and foliage dynamics), long-term water relations (13C discrimination data) and tree hydrology (natural abundance of deuterium).
The indicator shall be developed for the undisturbed humid (RBSF) and dry forests (Laipuna) of South Ecuador. Comparison with results from respective disturbed vegetation types will unveil effects on WUE due to land use change by forest fragmentation and isolation of trees. Because of their general applicability, functional indicators like WUE are especially useful for modelling approaches.
DFG funding ID 227674712
Homepage: www.tropicalmoutainforest.org