Calculation of Ecological Recovery Based on BP Neural Network: A Case Study of Zhuxi Small Watershed in Changting County, Fujian Province

Abstract

Environmental degeneration has seriously restricted the economic and social development of countries around the world. To tackle the problem, the projects of ecological restoration and reconstruction have been or are being carried out in many places. Under this background, many scholars try to assess the effects of ecological restoration through statistical method, comprehensive evaluation method, fuzzy evaluation method and grey evaluation method. However, it is difficult to discern the non鄄liner correlation between each assessment indicator and the degree of ecosystem restoration, as well as to decide the contribution ratio of each indicator. The methods mentioned above were complicated in assessing the contribution ratio of indicators; whereas, the back propagation neural network can solve the problems about non鄄linear model and contribution ratio of indicators effectively through adjusting the weight of each indicator automatically in the training process of this model. The research focuses on the small watershed of Zhuxi in Changting County, Fujian Province. The data was acquired from field investigation, lab analysis and remote sensing images which the features are extracted from. The ecosystem restoration model which can quantitatively evaluate the degree of the ecosystem restoration is built using back propagation neural network (BP鄄NN) by Matlab7.