Flood plains: critically threatened ecosystems

Abstract

Riparian zones, river-marginal wetland environments and flood plains are key landscape elements with a high diversity of natural functions and services. They are dynamic systems that are shaped by repeated erosion and deposition of sediment, inundation during rising water levels, and complex groundwater–surface water exchange processes (Chapter 3). This dynamic nature makes flood plains among the most biologically productive and diverse ecosystems on earth ( Junk et al. 1989; Gregory et al. 1991; Naiman & De´camps 1997; Tockner & Stanford 2002; Naiman et al. 2005). Flood plains are also of great cultural and economic importance; most early civilizations arose in fertile flood plains and throughout history people have learned to cultivate and use their rich resources. Flood plains have also served as focal points for urban development and exploitation of their natural functions.