PROBLEM TO BE SOLVED: To automatically extract zones by forest-type on the basis of only aerial laser measurement data.SOLUTION: A feature-amount-image generation unit 20 obtains predetermined feature amounts including a value of a ratio of a first pulse to total reflection pulses, a reflection intensity, and a tree height at each measurement spot on the basis of aerial laser measurement data 30 acquired by scanning a target area including forest, and generates a feature amount image of the target area for which pixel values are the feature amounts. A forest-type-zone generation unit 22 divides the target area into a plurality of regions on the feature amount image on the basis of feature amount similarity, and generates zones by forest-type.
