Transient ecosystem responses to free-air CO2 enrichment (FACE):: experimental evidence and methods of analysis

Ecosystem responses to the perturbation generated by a step CO2 increase in field CO2 experiments are different from those to a gradual Ca increase as in the real world. In order to develop our ability to predict ecosystem responses to a gradual Ca increase, we need to analyse data from FACE experiments using an inversion approach to challenge the structure of existing models and derive parameter values. In order to effectively conduct the inverse analysis, we need to collect highly accurate, informative data by improving experimental design and measurement plans for the FACE studies.