Method for determining range of large-scale complex terrain mountain system

The invention relates to a method for determining the range of a large-scale complex terrain mountain system, and belongs to the technical field of geography and protection area division. Aiming at large-scale complex terrains, the method comprises the following three aspects: aiming at a mountain system main body, determining a basic mountain system range by adopting a ridge line; integrating the river network with the ridge line to construct a mountain range framework; performing multi-threshold mountain system edge range fusion according to the standard that the mountain system range occupied by the plains and the hills does not exceed 10% of the total range in combination with river delimitation and valley delimitation principles to form a final mountain system boundary l3; according to the method, on the basis of accurately mastering the research range, the range of the mountain systems can be controlled, the boundary of the mountain systems can be drawn, and technical means are provided for dividing the