基于DEM的作物需水量估算方法

A Method for Evaluation Crop Water Requirements Based on Digital Elevation Model(DEM)

以ARCG IS8.3为技术平台,以“全国灌溉试验数据库”为主要数据源,以DEM为基础,通过ARCG IS的空间分析工具获取经度、纬度、海拔高度、坡度、坡向和遮蔽度等主要地形因子。在分析山东省冬小麦需水量与主要地形因子之间关系的基础上,利用趋势面分析方法建立了冬小麦需水量空间分布的数学模型,生成了山东省冬小麦需水量栅格图,所得结果与当地冬小麦实际用水分布状况较为吻合。

By employing geographic information software ArcGIS8. 3 and 1 km × 1 km DEM, 1 km × 1 km database in aspects of longitude, latitude, altitude, slope were established. Using “Database of National Irrigation Experimental Materials” and climate data from 1951 to 2003, the annual data of water requirement was confirmed. The relation between water requirement of winter wheat and main topographic factor were analyzed. On the base of the work, the spatial distribution model for crop water requirement was established in terms of different geographical dimensions as longitude, latitude, altitude, slope and aspect by using trendsurface analysis. Finally, the grid information system of winter wheat water requirement Shandong province in China was established. The evaluation data matches well with the experimental data observed.