基于LSSVM-CA模型的复杂土地利用变化模拟——以鄂州市为例

本文探索了最小二乘支持向量机（Least Squares Support Vector Machine ,LSSVM）获取元胞转换规则的可行性,并应用于复杂土地利用变化模拟预测。以湖北省鄂州市为研究区,以1991-2004年土地利用变化数据作为模型训练数据,运用改进的ROC分析方法对比分析了LSSVM和逻辑回归方法获取的元胞转换规则,在此基础上运用LSSVM-CA模型模拟了研究区2013年的土地利用情景,并对2020年和2030年土地利用情景进行预测。研究结果表明：①LSSVM对数量较大、变化过程较复杂土地利用类型的空间分布模拟效果更好,如耕地、建设用地、养殖水体和其他用地;②与2013年实际土地利用情景相比,LSSVM-CA模拟结果总体精度为0.80,Kappa系数为0.73,处于较高一致性水平,优于逻辑回归-CA模型结果;③未来,鄂州市主城区、城西新区、“葛华新城”、“红莲湖新城”以及南部的花湖开发区、沼山镇、太和镇建设用地需求较大,将占用大量耕地,东部和南部低丘岗地区的耕地将大量转变为林地。研究结论为LSSVM方法可用于获取元胞转换规则进行复杂土地利用变化模拟,并能取得较好的效果,模拟结果可为研究区土地规划、耕地和生态环境保护等提供决策参考。

Complex land use changes simulation in Ezhou City using cellular automata based on least squares support vector machine

Here we validate the feasibility of gaining transformation rules for cellular automata modeling using Least Squares Support Vector Machine （LSSVM）methods,and apply it to the simulation and prediction of complex land use change. We took land use change information from 1991 to 2004 for Ezhou,Hubei as training data. With the application of LSSVM and Logistic Regression methods,we obtained two sets of transformation rules respectively. Comparison and analysis were made between them with the help of an enhanced ROC method. We then simulated land use scenarios for 2013 using a united LSSVM-CA model and predictions to 2020 and 2030. The results show that the LSSVM method has a better output than the Logistic Regression method in simulating the spatial distribution of land use types that have a large area and a complex change process,such as cultivated land,construction land,aquaculture land and other land. Compared with the actual land use scenarios in 2013,the precision of simulation output derived from the LSSVM-CA model is 0.80. The Kappa coefficient is 0.73,which is at a high level of consistency and better than the simulation results gained from Logistic-CA model. In the future,some districts will have a large demand of construction land and a large number of cultivated land will be occupied. Farmland in the eastern and southern low-hilly area will transform into forest land in a big way. We conclude that the LSSVM method can be used to obtain transformation rules in a cellular automata model and can gain a good result in simulating land use changes. The simulation results provide meaningful decision-making reference points for the study area in land planning,farmland protection and ecological environmental protection.