Heard Island: Baseline Data for Monitoring Longterm Change. (a) Vegetation Mapping from Orthophotos.

Vegetation mapping from orthophotos derived from non-metric photography for the north eastern, south eastern, south, west and north west coastal areas of Heard Island.\r\n\r\nMore information about the vegetation mapping process is documented in a pdf report entitled 'Notes for Heard Island Vegetation Mapping project 2002-2006' available for download at the provided URL. The report is an updated version of the December 2004 pdf report entitled 'Heard Island Vegetation Mapping Report'.\r\n\r\nThe vegetation mapping project was undertaken between 1986 and 1988 (field mapping), 2002 and 2005 (digitising) and 2003-2004 (limited field checking). The data for the mapping done on orthophotos are contained in two shapefiles as follows:\r\n\r\n- Vegetation mapping polygons.\r\n\r\n- Reliability (comments on quality of orthophoto coverage, areas of overlapping cover, etc).\r\n\r\nAssociated shapefiles are as follows:\r\n\r\n- Aerial photo coverage, showing polygons for the areas where each orthophoto was used for mapping (see metadata record with ID HI_VEG_ORTHOPHOTOS_VEGMAP).\r\n\r\n- Photo locations of 35mm photos used during mapping (see metadata record with ID HI_VEG_PHOTOS_VEGMAP).

针对赫德岛东北、东南、南部、西部及西北沿海区域，基于非度量摄影生成的正射影像（orthophotos）开展植被填图工作。

有关该植被填图流程的详细信息，可参阅名为《赫德岛植被填图项目2002-2006年工作笔记》的PDF报告，该报告可通过指定URL下载，其为2004年12月发布的《赫德岛植被填图报告》的更新版本。

本植被填图项目的实施阶段包括：1986至1988年的野外填图、2002至2005年的数字化作业，以及2003至2004年的有限野外核查。基于正射影像完成的填图数据包含两个形状文件（shapefile），具体如下：

- 植被填图多边形矢量图层

- 可靠性评估文件（涵盖正射影像覆盖质量、重叠覆盖区域等相关说明）

关联的形状文件如下：

- 航空摄影覆盖范围图层：用于展示各正射影像用于填图的区域多边形，相关元数据（metadata）记录的ID为HI_VEG_ORTHOPHOTOS_VEGMAP

- 填图所用35毫米胶片摄影照片的点位图层，相关元数据（metadata）记录的ID为HI_VEG_PHOTOS_VEGMAP