GRSM_VEG_MILLER

This is a vector polygon file showing the historic range forest types at Great Smoky Mountains National Park. The data was collected from a historic map drawn by Frank Miller, Assistant Forester, in 1938. The map was scanned using a Vidar color scanner and the digital images were brought into ArcMap. The map was originally divided into 4 separate panels, thus there were 4 separate image files. Each image was Georectified, Clipped and then the Mosaic tool was employed to create one large map image. Two feature classes, one a point feature class and the other a polyline feature class, were then created. The polyline class was used to digitize the boundary of each area of vegetation and a point containing the attributes of each area was placed within. After digitizing, the polyline layer was converted to a polygon feature class and the attribute table from the point layer was joined to the corresponding polygon within the feature class. The corresponding Integration of Resource Management Applications (IRMA) NPS Data Store reference is Great Smoky Mountains National Park Miller Vegetation Map.本数据集为矢量多边形文件，展示了大烟山国家公园（Great Smoky Mountains National Park）历史分布的森林植被类型。数据源自1938年由林务助理弗兰克·米勒（Frank Miller）绘制的历史地图。该地图通过维达尔（Vidar）彩色扫描仪完成扫描，所得数字图像被导入ArcMap软件。该地图最初被划分为4个独立图幅，因此生成了4份独立的图像文件。对每份图像依次执行地理配准、裁剪操作，随后使用镶嵌工具（Mosaic tool）拼接为一张完整的地图图像。随后创建了两类要素类：一类为点要素类，另一类为折线要素类。研究人员利用折线要素类对每块植被区域的边界进行数字化描边，并在每块区域内部放置承载其属性信息的点要素。数字化完成后，将折线图层转换为多边形要素类，并将点图层的属性表关联至要素类中对应的多边形要素。本数据集对应的美国国家公园管理局（National Park Service, NPS）资源管理应用集成（Integration of Resource Management Applications, IRMA）数据存储参考条目为：大烟山国家公园米勒植被地图（Great Smoky Mountains National Park Miller Vegetation Map）。