West Falmouth Harbor Eelgrass Bed Extent, 2010, generalized

West Falmouth Harbor (West Falmouth, MA, USA) has been experiencing a dramatic increase in nitrogen loading from an upgradient municipal wastewater treatment facility since the early 2000’s. As part of a long-term study into the effects of this nitrogen enrichment, we have been assessing changes in the extent and health of the eelgrass (Zostera marina) community within the harbor. We conducted side scan sonar surveys and analyzed them using SonarWiz and ArcGIS to delineate the extent of continuous seagrass bed within the harbor. The goal of this dataset is to assess changes in eelgrass habitat extent; small bare patches within the larger seagrass bed due to anchor scars and mooring scouring were not digitized. Groundtruthing of the edges was done with a combination of diver surveys, underwater video, and surface surveys at low tide. Surveys were run in every year from 2010 through 2022 and we plan to continue them into future years. Data analysis is ongoing and shapefiles will be added as they are run through quality assessment. Details for the 2010 data collection and analysis are detailed in Hayn 2012: Exchange of nitrogen and phosphorus between a shallow estuary and coastal waters, Appendix 3, permanently archived at https://hdl.handle.net/1813/31380.

美国马萨诸塞州西法尔茅斯港（西法尔茅斯）自21世纪初以来，一直面临上游市政污水处理设施带来的氮负荷急剧攀升的问题。作为针对此次氮富集效应的长期研究项目之一，本团队持续评估港内鳗草（Zostera marina）群落的分布范围与健康状况变化。本研究采用侧扫声呐开展勘测，并借助SonarWiz与ArcGIS软件进行数据分析，以划定港内连片海草床的分布范围。本数据集旨在评估鳗草生境范围的变化情况；因锚痕与系泊冲刷导致的大型海草床内部小型裸露斑块未被数字化记录。海草床边界的地面验证工作结合了潜水员勘测、水下视频拍摄与低潮时的水面勘测三种方式。本勘测于2010至2022年间每年开展，团队计划将此项工作延续至后续年份。目前数据分析工作仍在进行中，待通过质量评估后将补充对应的形状文件（shapefile）。2010年的数据采集与分析细节详见Hayn于2012年发表的《浅河口与近岸水体间的氮磷交换》一文附录3，该内容永久存档于https://hdl.handle.net/1813/31380。