基于GIS和支持向量机模型的邯郸市降雨量空间分布研究

Spatial distribution of rainfall in Handan based on GISand support vector machine model

邯郸地处华北半湿润区,其降水波动和空间分布不均衡是影响区域农业规划、水资源开发的重要因素。利用邯郸市16个气象站点近31年逐年降水资料,以DEM坡度、坡向、经度、纬度等变量为预测因子,构建了基于支持向量机(SVM)的年降雨空间分布模型。结果表明,邯郸市年降均雨量为526.3±16.83mm,变异系数3.19%。降雨量与预测因子之间存在弱的全局相关性,局部存在非线性关系。线性、高斯核和Sigmoid核函数的SVM模型能够较好拟合降雨量与预测因子之间的关系,模型的R2介于0.70~0.76之间,RMSE 24.89~35.78mm。通过GIS可视化显示,邯郸市降雨量呈降雨呈现环状聚集分布,峰峰矿区、磁县、曲周和鸡泽为低值中心,邯郸县、馆陶等地为高值中心。

Handan is located in the semi-humid region of north China,and its precipitation fluctuation and spatial distribution imbalance are important factors affecting regional agricultural planning and water resources development.Based on the annual precipitation data of 16 meteorological stations in Handan in the past 31 years,the spatial distribution model of annual precipitation was constructed by using DEM slope,aspect,longitude,latitude and other variables as forecasting factors.The results show that the average annual rainfall in Handan is 526.3±16.83 mm,and the coefficient of variation is 3.19%.There is weak global correlation between rainfall amount and forecast factors,and local non-linear relationship.The linear,Gauss kernel and SIGMOID KERNEL SVM model can fit the relationship between rainfall amount and forecast factor well.The R2 of the model is between 0.70~0.76,and the RMSE is between 24.89~35.78 mm.The visualization of GIS shows that the rainfall in Handan presents a ring-like distribution,with the Fengfeng Mining District Mining area,Ci County,Quzhou County and Jize as low value centers and Handan County and Guantao County as high value centers.