Automation of Forest Inventory using Airborne Ranging Radar

Forest inventory methods based on data acquired with an airborne ranging radar are discussed. The approach can be used to partly automate present labour-dominated forest inventory methods. Using these methods, the mean and dominant tree height can be measured with a standard deviation of 1 metre. The stem volume per hectare can be estimated with a relative accuracy of 15 % by effectively counting the height distribution of the trees and by calculating the centre of backscattered power from the forest canopy profile for a stand with a diameter of 40 metres. The methods have been developed using a helicopter-borne 8-channel ranging scattero-meter HUTSCAT (Helsinki University of Technology SCATterometer) which can measure a radar forest canopy profile (FCP) with a range resolution of 65 cm.