The invention relates to the technical field of forest detection, and particularly discloses a
forest vegetation detection method and
system based on an unmanned aerial vehicle, the unmanned aerial vehicle carries a visible light camera, a spectrum camera and a
radar to collect visible light images, spectrum images and
radar data of a forest area, and a three-dimensional model of a tree is constructed based on the
radar data; the crown data and the
tree species of the trees are determined based on the visible light images and the spectral images, the accumulation, the
biomass and the carbon reserves of the trees are determined based on the three-dimensional model, the
tree species and the crown data, so that the total accumulation, the total
biomass and the total carbon reserves of all the trees in the target forest region are calculated, and manual inspection and sampling of the tree data are not needed; the forest detection time is shortened, the detection efficiency is improved, single
tree modeling is combined with the visible light image and the
spectral image to calculate the accumulation amount, the
biomass and the carbon reserve of each tree, the total accumulation amount, the total biomass and the total carbon reserve of the whole target forest area are obtained through summation, and the detection result is more accurate.