Approaches to Study Terrestrial Ecosystems

Abstract

In this chapter, different approaches to the study of terrestrial ecosystems are introduced. The chapter is organised in two main parts: observations and experiments. For both of these general approaches, many examples are given from around the globe, introduced by typical research questions and illustrated with photos. Observations can be done at the level of whole ecosystems, either as single-site studies or as multisite studies within large networks, often using new technologies to measure variables of interest or to access tall canopies. Transects and chrono-sequences are introduced and critically discussed. Grid-based inventories and applications of remote sensing techniques complement the observational approaches. Natural experiments—that is, sudden disturbances and slow continuous forcing—are also discussed. On the other hand, experiments can be carried out by manipulating pools and processes, and also by manipulating environmental conditions. Examples range from transplant and space-for-time experiments to fertilisation and irrigation trials and to roof and free-air carbon dioxide enrichment experiments. The relevance of appropriate controls and the existence of hidden treatments are discussed. Biodiversity experiments are explained in detail, as are experiments of management and changes in land cover. To conclude this chapter, artificial ecosystems are introduced and their benefits are explored.