Ecosystems change on a multitude of spatial and temporal scales. While analyses of ecosystem dynamics in short timespans have received much attention, the impacts of changes in the long term have, to a great extent, been neglected, provoking a lack of information and methodological know-how in this area. This book fills this gap by focusing on studies dealing with the investigation of complex, long-term ecological processes with regard to global change, the development of early warning systems, and the acquisition of a scientific basis for strategic conservation management and the sustainable use of ecosystems. Theoretical ecological questions of long-term processes, as well as an international dimension of long-term monitoring, observations and research are brought together. The outcome is an overview on different aspects of long-term ecological research. Concepts and results of case studies in both aquatic and terrestrial ecosystems are discussed. The different time dimensions, as well as scales from the community and ecosystems up to the landscape scale are included. Finally, research is linked with application in different fields of ecology, and urgent future infrastructural, methodological and research demands and challenges are described. This book will be of interest not only to ecologists, conservation biologists, biodiversity scientists and environmentalists, but also to administrators of protected areas and natural resource managers.