Research on Urban Land Ecological Suitability Evaluation Based on Gravity-Resistance Model: A Case of Deyang City in China

To overcome the shortage in traditional methods of land ecological suitability evaluation, this paper established a gravity-resistance model based on physical motion principle. This model simulated two processes—gravity and resistance evaluation to assess land ecological suitability evaluation, which can be expressed by the formula of when a study area--S is greater than 0, it should be recognized as suitable for construction, and the greater, more suitable for urban development. When S equals to 0, it should be prohibited for urban construction. Take Deyang as an example, factors of gravity and resistance which are crucial to the construction of city are selected according to the rules of stability, in dependence, representativeness. The weights of gravity factors were determined by Analytical Hierarchy Process (AHP) and the scores of resistance factors were determined by Pessimistic Decision Method. Based on the gravity-resistance model, Deyang was divided into four zones: prohibited, restricted, optimized and key areas, which are 40.45%, 16.23%, 23.77% and 19.54% respectively.