The Global Change Research Wetland (GCReW) is one of the most intensively studied tidal wetlands systems in the world, with the majority of the previous research spent on two native functional groups of plants (C3 sedges and C4 grasses) and the invasive reed Phragmites australis. These previous studies have been concentrated in clusters of long-term study plots which make up a relatively small and non-representative portion of a larger 22 hectare marsh. So far no studies have documented site-wide trends in elevation, plant species presence, and plant species dominance, which are needed for scaling up models of wetland response to sea-level rise. This data release documents three datasets collected in summer of 2016 in order to better quantify relationships between plant cover and elevation, to contextualize ongoing monitoring and experiments as well as support future planning at GCReW. First, we performed 48 hour occupations of four elevation monuments on the Smithsonian Environmental Research Center's campus, using total station GPS. This was done so that we could better reference marsh heights to North American Vertical Datum of 1988. One of these monuments was used as a base station for real-time kinematic GPS surveying. Second, we surveyed the bounds and elevations of long-term vegetation monitoring plots associated with the Tennembaum Marine Observatory Network. Third and finally we performed a 20 by 20 meter real time kinematic GPS elevation survey of the entire marsh, accompanied by Braun-Blaunquet avegetation survey to map the presence and relative dominance of wetland plant communities. These analysis data products provide valuable context to, and further research direction for, the temporally rich but spatially restricted plant and elevation data collected at GCReW over the last three decades.
Start date | End date |
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2016-06-06 | 2016-08-15 |
Rank name | Value |
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Genus | Amaranthus |
Genus | Distichlis |
Genus | Hibiscus |
Genus | Iva |
Genus | Kosteletzkya |
Genus | Phragmites |
Genus | Schoenoplectus |
Genus | Solidago |
Genus | Spartina |
Genus | Spartina |
Genus | Spartina |
Genus | Typha |
attribute name | definition | format, unit or codes |
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occupation_id | Unique identifier for each of four 2 day long elevation benchmark occupations with total station GPS. | a001 = TIDAL - By Telephone Pole a002 = FLUME a003 = TIDAL - DOCK a004 = SET 17 |
northing | Positional northing in Universal Transverse Mercater (UTM) zone 18N | meter |
easting | Positional easting in Universal Transverse Mercater (UTM) zone 18N | meter |
elevation | Elevation relative to North American Vertical Datum of 1988 (NAVD88) as determined by GEOID12a. | meter |
attribute name | definition | format, unit or codes |
---|---|---|
point_index | Unique integer for each elevation point of the summer indicating chronological order the survey points were collected in. | dimensionless |
survey_id | Description of two elevation surveys completed during summer 2016. | June 2016 TMON Survey = self explanitory July and August 2016 20m Grid Survey = self explanitory |
measurement_type | Reason for dating elevation position. | test = point represents a test of the equipment TMON vegetation plot = point represents a corner of a vegetatin plot observed as part of the Tennemaub Marine Observatory Network. Braun Blanquet vegetation plot = point represents a series of Braun Blanquet vegetation observations made across the marsh. marsh edge = point represents the edge of the marsh, taken opportunistically as convenient during the course of surveying. |
test_type | Type of test. | repeated boardwalk test = The test was part of a regular equipment check, measuring the same spot on a boardwalk adjacent to where the base station was set up. one off test = The point represents an in field test, or feature that was opportunistically surveyed, not assoicated with a vegetation plot, or regular equipment checks. |
transect_id | One of three transects of vegetation plots associated with the Tennenbaum Marine Obesrvatory Network (TMON). | g1 = GCREW site transect number 1. g2 = GCREW site transect number 2. g3 = GCREW site transect number 3. |
plot_id | Integer indicating a unique plot number. | dimensionless |
corner | For vegetation plots associated with the Tennenbaum Marine Obesrvatory Network (TMON), we surveyed each of four corners. | dimensionless |
replicate_id | Unique integer for any points that were measured repeatedly, | dimensionless |
easting | Positional easting in Universal Transverse Mercater (UTM) zone 18N | meter |
northing | Positional northing in Universal Transverse Mercater (UTM) zone 18N | meter |
elevation | Elevation relative to North American Vertical Datum of 1988 (NAVD88) as determined by GEOID12a. | meter |
positional_notes | Miscelaneous notes on positional measurement. |
attribute name | definition | format, unit or codes |
---|---|---|
plot_id | Integer indicating a unique plot number. | dimensionless |
bb_cover | Braun Blonquet cover class. | 0 = Cover represents a trace observation, <1% cover. 1 = 1-5% cover 2 = 5-25% cover 3 = 25-50% cover 4 = 50-75% cover 5 = 75-100% cover |
cover_type | Species community or cover code associated with the cover class. | Dead = Dead vegetation thatch. SCAM = Schoenoplectus americanus TYLA = Typha latifolia IVFR = Iva frutescens SPCY = Spartina cynosuroides BareOrWater = Either bare ground or open water. PHAU = Phragmites australis SPAL = Spartina alterniflora C4 = Spartina patens and Distichlis spicata mix KOVI = Kosteletzkya virginica AMAR = Amaranthus cannabinus Hibiscus = Hibiscus moscheutos SOSE = Solidago sempervirens Unknown = Species was unidentified in the filed, or undecipherable from field notes. |
height_min | Minimum height of vegetation in plot. | meter |
height_max | Maximum height of vegetation in plot. | meter |
cover_notes | Miscelaneous notes on vegetation cover. |
unit name | parent SI unit | unit type | description |
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This dataset is listed under a Creative Commons BY 4.0 and can be used with attribution. https://creativecommons.org/licenses/by/4.0/