Terrain factors in hydrology

Terrain controls the movement and destination of all water reaching the land from the atmosphere. This is the subject of ‘geographical hydrology’ (Knapp, 1979) and one of the divisions of Chorley’s Water, Earth and Man (1969). It includes ‘hillslope hydrology’ dealing with slope effects on unchannelled water flow and ‘hydraulic geometry’ covering the relations between channel form and discharge. It overlaps with ‘hydrogeology’ although the latter is also concerned with water at greater depths in the earth’s crust.