Flood pulsing and the linkages between terrestrial, aquatic, and wetland systems

Lirnnologists have studied links between terrestrial and aquatic ecosystems since August Thienemann's time at the beginning of the last century; however, emphasis was placed mostly on input from the catchment area to water bodies, whereas productivity and nutrient cycles in floodplains were less intensively studied. This view has considerably changed during past decades, when increasing man-made modifications of river-floodplain systems led to severe negative ecological and economic side effects worldwide and stimulated very costly flood protection and rehabilitation projects. Studies have shown complex flood-induced interactions of rivers with their floodplains with respect to hydrology, geornorphology, biota, and biogeochernical cycles. These studies have led to the formulation of the Flood Pulse Concept (FPC) and several other, sometimes competing concepts to integrate the rapidly increasing amount of data and to improve predictions on the impact of human activities on river-floodplain systems. This process is far from being complete, and, because of its scientific complexity and economic magnitude, it can be considered one of the major challenges for limnologists in the next decade. This paper describes the current status, discusses controversial publications on the FPC, and points to open questions that should be answered in the future.