Sydney Harbour Coastal Saltmarsh Ecological Endangered Community. VIS_ID 4157

An assessment of saltmarsh of Sydney Harbour and the Parramatta River by NSW Department of Primary Industries, Cronulla. The first map showing the distribution of saltmarsh for the Parramatta River-Sydney Harbour estuary was created from aerial photos taken in the late 1970s (West et al. 1985). A subsequent map prepared from photos taken in 2000 (West et al. 2004) suggested there had been little change in distribution. However, recent anecdotal reports indicate that there may be many more small patches of saltmarsh than can be defined with aerial photography. Aerial photography and pedestrian survey were used to locate saltmarsh on the foreshore of the Parramatta River-Sydney Harbour, including the estuarine portions of Middle Harbour, Lane Cove River and Duck River. The location, condition and species composition of each patch was determined. Saltmarsh was defined as any intertidal community containing one or more species defined as "Characteristic Species" by the NSW Scientific Committee (2004) in its listing of Coastal Saltmarsh as an Endangered Ecological Community. The most recent aerial photographic coverage of the catchment of the Parramatta River was obtained. The boundaries of saltmarsh were mapped via onscreen digitising using Arcview version 3.3. To ensure consistent spatial accuracy, all digitising was carried out at an onscreen scale of 1: 700 or better. Presumptive maps of saltmarsh were printed at various scales to facilitate on-ground observations. Comprehensive pedestrian and boat based field surveys were carried out of the estuary's entire shoreline, with all saltmarsh patches identified field recorded, regardless of size. The results of field surveys were used to correct and re digitise the preliminary map as appropriate. \r\n\r\nThis 2006 version was supplied as a final step to Stage 2 in 2008. It has less polygons (757) than the former version (772).\r\n\r\nVIS_ID 4157

本数据集由新南威尔士州 primary产业部（NSW Department of Primary Industries）克罗纳拉分支机构完成，针对悉尼港与帕拉马塔河的盐沼（saltmarsh）开展评估。首张帕拉马塔河-悉尼港河口盐沼分布地图基于1970年代末的航空影像绘制完成（West等，1985）。后续基于2000年航空影像制作的盐沼分布地图（West等，2004）显示，盐沼的分布几乎未发生明显变化。但近期的非官方传闻显示，盐沼的小型斑块数量或许远超航空影像所能识别的范围。本次研究采用航空摄影与徒步勘测相结合的手段，对帕拉马塔河-悉尼港沿岸（涵盖中港、莱恩考夫河与达克河的河口段）的盐沼进行定位，并测定了每一处盐沼斑块的位置、健康状态与物种组成。本研究对盐沼的定义为：包含新南威尔士州科学委员会（NSW Scientific Committee，2004）在《海岸盐沼濒危生态群落名录》中划定的一种或多种‘特征物种’的潮间带群落。研究获取了帕拉马塔河流域最新的航空影像数据，采用ArcView 3.3版本软件，通过屏幕数字化操作绘制盐沼斑块的边界。为确保空间精度的一致性，所有数字化操作均在1:700及更高的屏幕比例尺下完成。研究人员将初步推定的盐沼地图按多种比例尺打印，以辅助野外实地观测。研究团队对该河口的全部岸线开展了全面的徒步与乘船野外勘测，对所有盐沼斑块（无论尺寸大小）均进行了实地识别与记录。随后根据野外勘测结果对初步绘制的地图进行修正，并按需重新开展数字化处理。

本数据集的2006版于2008年作为第二阶段的最终成果提交，其多边形数量（757个）少于旧版（772个）。
数据集唯一标识（VIS_ID）为4157