Rainfall simulation experiments as a tool for process research in soil science, hydrology, and geomorphology

Rainfall simulators are one of the most popular research devices for studying the impacts of rainfall on activation of runoff, infiltration, and sediment transport mobilization in the landscape. The research covers also related processes such as generation mechanisms of overland flow, interrail and rill erosion, soil compaction, soil surface changes, sealing, crusting, solutes transport, and others. Regarding the high number of research goals, different fields of application, and, finally, also due to the technical creativity of the research staff, several different rainfall simulator types are available and the standardization is not in sight. In this chapter, the differences in the existing devices with their pros and cons, the different research applications as well as the constraints, needs, and challenges for a future use are explained and some application examples included.