2010 Index of Stream Condition - River Centre Lines at the Reach Level

The ISC2010_RIVER_CENTRELINE_R line features represent the set of river reaches that are assessed in the 2010 ISC. The line features represents the middle of the river channel and have been defined as the midpoint of the ISC2010_STREAMBED_WIDTH polygon feature. This data set represents a re-alignment of the ISC2004 River Reaches. River centre lines have been connected at Reach ends and flow direction has been enforced. Each Reach has Metric Statistics assessed and recorded in Reach Summary (_R) Tabes. The ISC2010_RIVER_CENTRELINE_R is designed to JOIN to all ISC2010__R tables.The ISC2010_RIVER_CENTRELINE_REACH acts as the spatial key to which all other Physical Form and Riparian Vegetation reach metric statistics can be linked.River condition in Victoria is assessed every 5 years using the Index of Stream Condition (ISC). The Department of Environment and Primary Industries (DEPI) developed a methodology to assess the Physical Form and Riparian Vegetation components of the ISC using remote sensing data, specifically LIDAR and aerial photography. A State Wide mapping project was undertaken in 2010-13 to accurately map the Physical Form and Riparian Vegetation metrics of the ISC . Other ISC metrics were not assessed in the project and were derived from other sources.The Physical Form and Riparian Vegetation Metric products are a combination of mapped Vector and Raster data as well as Tabular Summary Statistics about the mapped features. In the context of the project, the term Metrics is used to refer to both the mapped features and the summary statistics. Remote sensing data used includes 15cm true colour and infra-red aerial photography and four return multi-pulse LiDAR data. This source data was used to derive a variety of Raster data sets including Digital Terrain Models, Slope, Vegetation Height and Vegetation Cover. The Digital Terrain and Slope rasters were used to map Physical Form metrics including Stream Bed, Top of Bank and River Centre Lines while the Vegetation Height and Cover rasters were used to map the Riparian Vegetation metrics.The Project Report "Aerial Remote Sensing for Physical Channel Form and Riparian Vegetation Mapping" describes the remote sensing and mapping approach used to create this data set.

ISC2010_RIVER_CENTRELINE_R 线要素（line features）代表2010年河流状况指数（Index of Stream Condition, ISC）评估中覆盖的全部河段集合。此类线要素代表河道中心线，其定义为ISC2010_STREAMBED_WIDTH多边形要素（polygon feature）的中点。本数据集是对ISC2004年河段数据的重新对齐处理。河段端点处的河道中心线已完成衔接，且已统一设定流向。每个河段的度量统计信息均已完成评估，并记录于河段摘要（_R）表格中。ISC2010_RIVER_CENTRELINE_R 设计用于与所有ISC2010__R数据表进行关联联结（JOIN）。ISC2010_RIVER_CENTRELINE_REACH 作为空间键（spatial key），可关联所有其他河流物理形态与河岸植被的河段度量统计信息。

维多利亚州每5年采用河流状况指数（ISC）开展一次河流状况评估。环境与初级产业部（Department of Environment and Primary Industries, DEPI）开发了一套评估方法，利用遥感数据（尤其是激光雷达（LiDAR）与航空摄影）来评估ISC的河流物理形态与河岸植被组分。2010至2013年间，一项全州范围制图项目正式实施，旨在精准绘制ISC的河流物理形态与河岸植被度量指标。本项目未对其余ISC度量指标开展评估，相关数据取自其他来源。

河流物理形态与河岸植被度量产品整合了矢量（Vector）与栅格（Raster）制图数据，以及关于制图要素的表格摘要统计信息。在本项目语境中，“度量指标（Metrics）”一词同时指代制图要素与摘要统计信息。本次使用的遥感数据包括15cm分辨率真彩色与红外航空摄影，以及四次回波多脉冲激光雷达（LiDAR）数据。基于该原始遥感数据，已衍生出多种栅格数据集，包括数字地形模型（Digital Terrain Models）、坡度、植被高度与植被覆盖度数据。其中，数字地形与坡度栅格被用于绘制河流物理形态度量指标，涵盖河床、岸顶与河道中心线；而植被高度与覆盖度栅格则被用于绘制河岸植被度量指标。本项目的研究报告"Aerial Remote Sensing for Physical Channel Form and Riparian Vegetation Mapping"详细阐述了用于创建本数据集的遥感与制图技术方案。