Topography Aspect - Ipswich Watershed - Idrisi Raster File

This datalayer is part of a group of layers used for research in the Ipswich River Watershed. This is the aspect model for the study area. The source elevation tile data was provided on the MassGIS website www.state.ma.us/mgis/massgis.htm in ESRI-format shapefile format and imported into IDRISI software using the ShapeIdr command. The resulting vector elevation files were converted to raster format using successive Lineras macro commands. This has the effect of mosaicing the tiles as well. The raster image was filtered once using a low-pass (mean) filter, then masked to the Ipswich study area parameters (extent). The aspect map was created using the surface analysis module. This datalayer was produced as part of a research project concerning the Ipswich River Watershed.

本数据图层为用于伊普斯维奇河流域（Ipswich River Watershed）研究的一组图层之一，对应本研究区的坡向模型。原始高程瓦片数据由马萨诸塞州地理信息系统（MassGIS）官网（www.state.ma.us/mgis/massgis.htm）提供，格式为ESRI格式的Shapefile（Shapefile），通过ShapeIdr命令导入至IDRISI软件中。生成的矢量高程文件通过连续执行Lineras宏命令转换为栅格格式，该过程同时完成了瓦片拼接。随后对生成的栅格影像进行一次低通（均值）滤波处理，并基于伊普斯维奇研究区的参数（研究范围）进行掩膜裁剪。最终通过地表分析模块（surface analysis module）生成坡向地图。本数据图层为伊普斯维奇河流域相关研究项目的产出成果之一。