Tidal levels in Nine Marshes on the Virginia Coast, 2018-2019

To determine the tidal range at each marsh, water depth was measured using Onset HOBO Water Level Data Loggers for a period of approximately 30 days. There are two data tables. One contains the water level data, adjusted for air pressure. The second contains the elevations of each well relative to NAVD88. Water depth was measured using Onset HOBO Water Level Data Loggers (Part #U20L-04) for a period of approximately 30 days within each marsh at the boundary of tall-form Spartina alterniflora and short-form S. alterniflora. Three HOBO loggers were available for use in this study; thus, water levels in all nine marshes could not be made at the same time. Water levels were measured in sets of three marshes, simultaneously, by placing one logger in each of three marshes. After about one month, the loggers were removed from a marsh, the data downloaded, and the loggers moved to another set of three marshes. Thus, for the nine sites in this study, three HOBO water-level-logger deployments were made: GATR Tract, Cushman's Landing, and Steelman's Landing from July 6th to August 6th, 2018; Oyster Harbor, Indiantown, and Box Tree from October 8th to November 4th, 2018; and Upper Phillip's Creek, Woodland Farm, and Green's Creek from November 4th to December 4th, 2018.为测定各盐沼的潮差，研究人员采用型号为Part #U20L-04的Onset HOBO水位数据记录仪（Onset HOBO Water Level Data Loggers），在每个盐沼的高株互花米草（Spartina alterniflora）与矮株互花米草（S. alterniflora）交界带内开展了为期约30天的水深测量。本数据集包含两张数据表：其一为经大气压力校正的水位数据，其二为各监测井相对于北美垂直基准面1988（NAVD88）的高程值。本次研究仅配备三台HOBO记录仪，因此无法同时对全部9个盐沼完成水位监测。研究采用分批轮换的布设方案：每次同时在3个盐沼中各放置一台记录仪，同步开展水位观测；待运行满约1个月后，将对应盐沼内的记录仪取回并导出数据，随后将其转移至下一批3个盐沼中。据此，本研究针对9个监测点位共开展了3轮HOBO水位记录仪部署：2018年7月6日至8月6日，部署于GATR Tract、Cushman's Landing及Steelman's Landing；2018年10月8日至11月4日，部署于Oyster Harbor、Indiantown及Box Tree；2018年11月4日至12月4日，部署于Upper Phillip's Creek、Woodland Farm及Green's Creek。