Maryland Archived Submerged Aquatic Vegetation - SAV 2019

The Chesapeake Bay SAV Coverage was mapped from digital multispectral imagery with a 25cm GSD to assess water quality in the Bay. Each area of SAV was interpreted from the rectified imagery and classified into one of four density classes by the percentage of cover. The SAV beds were entered into an SDE GIS feature 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 at https://imap.maryland.gov. Feature Service Link: https://mdgeodata.md.gov/archive/rest/services/Biota/MD_ArchivedSubmergedAquaticVegetation/FeatureServer/34切萨皮克湾沉水植物（Submerged Aquatic Vegetation, SAV）覆盖数据集采用地面采样距离（Ground Sample Distance, GSD）为25cm的数字多光谱影像完成制图，以评估该海湾的水质状况。研究人员通过校正后的影像解译所有沉水植物区域，并依据覆盖百分比将其划分为4个密度等级之一。随后依照下文所述的质量控制流程，将沉水植物床录入至空间数据引擎（Spatial Data Engine, SDE）地理信息系统（Geographic Information System, GIS）要素类中。 本数据集涵盖所有已航测区域内识别出的沉水植物区域。部分被认定无沉水植物的区域未开展航测作业；部分小型沉水植物床（尤其是狭窄支流沿岸区域）可能无法在航空影像中被识别。 本数据集为马里兰州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/34