Introduction

Abstract

All land is part of a watershed or river basin and the water, which flows over it and through it, shapes all landscapes. Figure 1 shows the landscape sculptured by erosion in Greece and the very dry land in Egypt. Indeed, rivers are such an integral part of the land that in many places it would be as appropriate to talk of riverscapes as it would be of landscapes. Rivers are much more than merely water flowing to the sea. Rivers carry downhill not just water, but just as importantly sediments, dissolved minerals, the nutrient-rich detritus of plants and animals. Their ever-shifting beds and banks and the groundwater below are all integral parts of rivers. Even the meadows, forests, marshes and backwaters of floodplains can be seen as part of the rivers—and the rivers as part of them.