Vegetation and climate - an introduction
Deil, Ulrich; Loidi, Javier
Within the series of 42 IAVS-Symposia, the interactions between "vegetation and climate" have been discussed twice: At the 1975-Congress in Rinteln/Germany this was the only topic. And for the 1999 symposium in Bilbao/Spain it was chosen as the main subject by the organizers (a survey of all the topics in Bilbao is given in the following article by Loidi). At both meetings, the majority of contributions focussed on meso-scalic climate and vegetation patterns. Another frequent topic of discussions is provided by phenological phenomena. Micrometeorological effects on plants - the modifications of the microclimate by the plant cover and adaptations of plants to extreme climatic conditions - were significant in the 70s, when ecosystematic approaches and ecophysiological methods arose. Those aspects were not in the centre of interest in Bilbao, but other questions emerged: How will the plant cover react to human induced climatic changes? And can we model those responses and make realistic predictions? This issue presents a cross-section of the various perspectives from which the interrelations between the bio- and the atmosphere can be discussed. The sequence of papers was arranged according to three aspects: A) Climatic changes and their effect on vegetation, B) Phenological phenomena, and C) Climatic gradients and vegetation patterns at medium to small spatial scales.