LASER ALTIMETER MEASUREMENTS AT WALNUT-GULCH WATERSHED, ARIZONA

Measurements of landscape surface roughness properties are necessary f or understanding many watershed processes. This paper reviews the use of an airborne laser altimeter to measure topography and surface rough ness properties of the landscape at Walnut Gulch Watershed in Arizona. Airborne laser data were used to measure macro and micro topography a s well as canopy topography, height, cover, and distribution. Macro to pography of landscape profiles for segments up to 5 km (3 mi) were mea sured and were in agreement with available topographic maps but provid ed more detail Gullies and stream channel cross-sections and their ass ociated floodplains were measured. Laser measurements of vegetation pr operties (height and cover) were highly correlated with ground measure ments. Landscape segments for any length can be used to measure these landscape roughness properties. Airborne laser altimeter measurements of landscape profiles can provide detailed information on watershed su rface properties improving the management of watersheds.