MEASURING CANOPY STRUCTURE WITH AN AIRBORNE LASER ALTIMETER

Quantification of vegetation patterns and properties is needed to dete rmine their role on the landscape and to develop management plans to c onserve our natural resources. Quantifying vegetation patterns from th e ground, or by using aerial photography or satellite imagery is diffi cult, time consuming, and often expensive. Digital data from an airbor ne laser altimeter offer an alternative method to quantify selected ve getation properties and patterns of forest and range vegetation. Airbo rne laser data found canopy heights varied from 2 to 6 m within even-a ged pine forests. Maximum canopy heights measured with the laser altim eter were significantly correlated to measurements made with ground-ba sed methods. Canopy shape could be used to distinguish deciduous and e vergreen trees. In rangeland areas, vegetation heights, spatial patter ns, and canopy cover measured with the laser altimeter were significan tly related with field measurements. These studies demonstrate the pot ential of airborne laser data to measure canopy structure and properti es for large areas quickly and quantitatively.