DEVELOPMENT OF PHENOLOGICAL MODELS OVER TIME – A REVIEW

An overview is given over the historical development of phenological models with particular emphasis on models used for predicting early phenological stages in fruit tree species. It is shown that the mechanistic understanding of the physiological processes is still very limited. Therefore statistical approaches to arrive at predictive models are common. These, however, are limited to the site or area where they were developed and therefore are of very limited use in climate impact studies. At last, an outlook is given on how one might be able to overcome the limitations of current approaches even if the understanding of the underlying physiological processes driving plant development is still limited.