Simulation Of Land Use Change In Chakou Small Watershed Based On CLUE-S Model

Research of land use change is the main content in the field of environmental change, changes of land use spatial distribution pattern fundamentally has a far-reaching influence on the structure and function of ecological system. Land-use also has a profound impact on the use of natural resources, ecological and environmental protection and economic development. So CLUE-S model is a reliable model to research the conversion of land use and its effects at small regional extent.In this paper we select the land use status quo data of the year 2003,2008,2008.We use Logistic regression method to analyse the relationships between the land use types and the driving factors, then we using the CLUE-S model to simulate the land use pattern of the study area in 2013 to verify whether the model is suitable for the watershed. Finally, we constructs land development scenarios of the future by combining the characteristics of land use change with historical use in the study area, to simulate and comparatively analyze the space change area of land use types distribution pattern in different scenarios around 2023.The main conclusions are as follows:1. We use the land use types change, dynamic change and space transfer to analyze land use change in the study area. The results shows that the main land use types in the study area are cultivated land, woodland and grassland. The land use change in Chakou river basin mainly happened during the period of 2008-2013, one of the most important change is the transformation of slope farmland to terrace.2. According to the characteristics of land use change in the study area and the model requirements to determine the simulation for slope arable land, terraced fields, ditch dam farmland, ditch river farmland, orchard, woodland, grassland, rural residential areas. According to the data source we select the accessibility, topography, soil and other driver factors, and uses logistic regression method to analyze the correlation between all land use types and the driving factors. The average ROC value of the regression results is 0.89 indicates that the selected driving factors have a stronger ability to explain the distribution of land use types.3. The Kappa coefficients of the simulation outcomes are 0.96 and 0.91,which indicating the CLUE-S model is suitable for the simulation of land use change in the study area. By means of setting the location preference variables to reflect the land use policy in study area, the model correctly simulate the distribution of terraces. The simulation of some types which have too much changes are not satisfactory without considering the space policy of other land use types, which from the side reflect the parameter setting sensitivity of the model as well as the impact of land use policies for the changes of the spatial pattern.4. Based on the trends, agricultural development and ecological protection, we build different scenarios, comparing the simulation results of different scenarios with the land use status dates in 2013 to analyze the changes of land use types in terms of quantity and space in study area. During the development process of the land use in study area, ditch dam farmland, ditch river farmland, rural residential areas maintain the status quo, slope farmland and grassland will decrease into terraced field, orchard and woodland. The northwest, Southeast and central slope cultivated field in the chakou river basin may become the region of land use change in future.