Maryland Archived Submerged Aquatic Vegetation - SAV 2013

The 2013 Chesapeake Bay SAV Coverage was mapped from 1:24,000 black and white aerial photography to assess water quality in the Bay. Each area of SAV was interpreted from the rectified photography and classified into one of four density classes by the percentage of cover. The SAV beds were entered into an SDE GIS fetaure class using the quality control procedures documented below. The dataset contains all SAV areas that were identified from the areas flown. Some areas that are presumed to contain no SAV were not flown. Some small beds, particularly along narrow tributaries may not have been distinguishable on the aerial photography. This is a MD iMAP hosted service. Find more information on https://imap.maryland.gov. Feature Service Link: https://mdgeodata.md.gov/archive/rest/services/Biota/MD_ArchivedSubmergedAquaticVegetation/FeatureServer/282013年切萨皮克湾水生维管植物（Submerged Aquatic Vegetation，SAV）覆盖图基于1:24000比例尺黑白航空摄影测绘生成，用于评估该海湾的水质状况。研究人员通过正射校正后的航空影像解译所有水生维管植物区域，并依据植被覆盖百分比将其划分为四个密度等级。随后按照下文所述的质量控制流程，将这些水生维管植物床体导入空间数据库引擎（Spatial Database Engine，SDE）地理信息系统（Geographic Information System，GIS）要素类中。本数据集涵盖了所有航飞区域内识别出的水生维管植物区域。部分推定无水生维管植物的区域未开展航飞作业；部分小型床体，尤其是沿狭窄支流分布的床体，可能无法在航空摄影中被分辨识别。本服务为马里兰州iMAP托管服务，更多信息可访问https://imap.maryland.gov。要素服务链接：https://mdgeodata.md.gov/archive/rest/services/Biota/MD_ArchivedSubmergedAquaticVegetation/FeatureServer/28