1 - The groundwater/surface water ecotone perspective: state of the art

Summary

ABSTRACT This paper considers the increased interest in groundwater/surface water ecotones. That clearly appeared within the framework of the UNESCO/MAB and IHP projects on the role of land/inland water ecotones in landscape management and restoration. Groundwater/Surface water ecotones are transition zones, the limits between very contrasted systems. At different space and time scales they provide, favour, filter or stop exchanges and they can also modify interactions between ecosystems. This paper outlines the content and the structure of the book.

BACKGROUND

January 1991 marks the official start of the joint project between the Man and the Biosphere Programme (MAB) and the International Hydrological Programme (IHP) of UNESCO on the role of land/inland water ecotones in landscape management and restoration. The launching of this project was due to the increasing awareness of the important role played by ecotones between terrestrial and aquatic systems in the landscape and in natural resource management (Di Castri et al., 1988; Naiman & Decamps, 1990; Holland & Risser, 1991; Hansen & Di Castri, 1992). They play an essential role as controls for the movement of water and materials throughout the landscape. They are zones where ecological processes are more intense and resources more diversified. The interface favours species dispersal. They are also zones which react quickly to human influences and changes in environmental variables.

Considering the key role of land/inland water ecotones, UNESCO/MAB and IHP launched a collaborative research project with the aim of determining the management options for the conservation and restoration of land/inland-water ecotones through increased understanding of ecological processes. Within this framework, a sub-network was devoted to groundwater/surface water ecotones.