Sapelo Research Application Form


Research Application ID:  GCE-37-2012 (submitted: 10/05/2012, status: approved)

Provide a brief title for web display

Micrometeorological flux tower installation

Investigator Information

On Island Sponsor: GCE SINERR UGAMI GADNR

Principal Investigator: Daniela Di Iorio
Home Institution: University of Georgia
Award Information: NSF LTER GCE III, flux tower
Mailing Address: Dept. of Marine Sciences Phone Number: (706) 542-7020
  University of Georgia E-mail Address: daniela@uga.edu
  Athens, Georgia 30602-3636  
Co-investigators: Monique Y. Leclerc (University of Georgia)

Briefly describe the project goals and methodology

The purpose of this research is to evaluate the exchange of gases between salt marshes and the atmosphere, in order to understand the role that these wetlands play in the carbon cycle, to be able to model water flow in the Duplin River, and to be in a position to predict the effects of future changes such as sea level rise. We will install an eddy covariance flux tower in a Spartina alterniflora dominated marsh at the head of a small creek off the Duplin River to study exchange of heat, water and carbon between the marsh and the atmosphere. Data collected from this instrumentation and research results obtained will also benefit the Sapelo Island National Estuarine Research Reserve (SINERR) in understanding climate change, sea level rise and marshland response.

Communications and data transmission between the tower and a base station will be with license-free 900 MHz spread-spectrum radios with Yagi antennas. Radio transmission power is limited in the modems to comply with Federal Communications Commission (FCC) regulations (<1W). The maximum range for transmission (line-of-site) is about 20 miles, but <0.5 mile if there are obstructions like trees. In transmission tests, we received strong signals from the interior marshes up the Duplin River to Marsh Landing (≤5 miles). These tests have also shown that radio transmission to the UGA Marine Institute is not possible as the upland forest blocks the signals. Thus a base station will be set up at Marsh Landing where a data and communications server will be installed. An Internet line at Marsh Landing will then be used to send the data to UGA for processing and analysis.

Where will the project be located?

Duplin River, 31°26'38.56" N, 81°17'0.70"W, see attached permit application for further details

How will you provide GPS coordinates for study sites?

GPS coordinates are listed in the project location field

What are the expected start and end dates of the project?

Start Date:  11/01/2012 End Date:  (ongoing)

How many people will access the site and at what frequency?

2 people daily for installation of boardwalk and platform, then 2 people for monthly maintenance.

Please list keywords (as many as are appropriate) that describe your project:

Taxonomic/Functional group: plants

Organisms: Spartina

Habitat type: marsh, creek

Measurements: gas exchange, heat flux, temperature, pressure, radiation

Study theme: atmospheric science

Likely long-term impacts of the study: permanent structure installation

What equipment will be deployed in the field?

The eddy covariance flux tower is an advanced weather station that not only measures standard meteorological parameters but also carbon and water concentrations at fast sampling rates. Instrumentation on the tower will include two sonic anemometers and two closed-path infrared gas analyzers to measure the three-dimensional wind vector, air temperature, and concentrations of CO2 and H2O at two heights. Other instrumentation will include soil sensors (soil heat plates, an averaging thermocouple, a soil water content reflectometer, and a pressure transducer for water level), atmospheric sensors (humidity, temperature, pressure, rainfall), up and down looking radiation sensors (short wave, long wave and photosynthetically active radiation) and a digital camera to document the growth cycle of Spartina alterniflora. The tower will be powered by solar panels placed within 30 feet of the tower that recharge a bank of batteries housed on the flux tower platform.

Will plants or animals be collected as part of this study?

No.

What are the likely impacts of the project on the site?

The flux tower itself will be about 30 feet tall erected on a platform 5′x5′ square. It will be powered by 6 solar panels and accessed via a boardwalk for servicing and maintenance (approximately once a month). The boardwalk will be approximately 220 m in length and will be constructed from the head of Factory Creek to the tower site. Access from the head of Factory Creek is shorter than access from the Duplin River and it is also isolated from general boating traffic. We do not want unauthorized people having access to the flux tower. The total square footage over vegetated marsh for this project is approximately: 26(tower platform)+24(solar panels)+843(boardwalk)=892 sqft.

Will the project design include boardwalks? If not, explain why not.

Yes. In order to limit the impact on the Spartina marsh we will install a boardwalk. This area is dominated by medium and short Spartina alterniflora that will grow to heights of approximately 0.5-1 m and 0.05-0.5 m, respectively. In order to minimize our impact, the decking material that will be used is ThruFlow flooring system (http://www.thruflow.com/) so that light can penetrate to the marsh surface. For a deck raised 3 feet from the marsh surface, 70% of the light availability will penetrate to the surface below, thus allowing Spartina alterniflora to grow beneath the tower platform and boardwalk. The decking will be raised 3 feet (0.9 m) above the marsh surface. According to real time kinematic (RTK) satellite navigation surveys the marsh elevation at this location is approximately 2.0 m above MLLW. Since the highest tide is 2.9 m relative to MLLW, the boardwalk and platform will be at a level of the highest tide that floods the marsh.

All lumber used in the construction of the tower platform, boardwalk, and solar panel mounts will be fiber-reinforced polymer lumber, commonly referred to as FRP lumber (a description from one companies' webpage is http://www.compositetimbers.com/ACT_advantage.html). We will not use pressure treated lumber, as we do not want any chemicals leaching into the marsh that will impact Spartina alterniflora growth.

How long will impacts persist after the research is concluded?

Boardwalk and platform will be removed when the project is completed unless we or SINERR use them for a new project.

Research Permits:

U.S. Army Corps of Engineers: GCE-37-2012_Permit_ACOE (10/23/2012-10/23/2014)

Georgia DNR Coastal Resources Division: GCE-37-2012_Permit_CMPA_803 (07/26/2022-07/26/2027)

Georgia DNR Coastal Resources Division: GCE-37-2012_Permit_Flux_Tower_CRD_permit (12/02/2012-indefinite)

Study Area Map:

Files attached to this application

GCE-37-2012_General_AppendixB_2012_PCN_Form-DiIorio.pdf  (PDF file, 1113.01 kb, submitted 10/05/2012)
[web link: https://gce-lter.marsci.uga.edu/private/registration/files/General/GCE-37-2012_General_AppendixB_2012_PCN_Form-DiIorio.pdf]

GCE-37-2012_General_scanned_flux_tower_permit.pdf  (PDF file, 1588.57 kb, submitted 10/05/2012)
[web link: https://gce-lter.marsci.uga.edu/private/registration/files/General/GCE-37-2012_General_scanned_flux_tower_permit.pdf]

GCE-37-2012_Maps_DiIorio_Flux_Tower.kmz  (Compressed KML file, 0.68 kb, submitted 10/06/2012)
[web link: https://gce-lter.marsci.uga.edu/private/registration/files/Maps/GCE-37-2012_Maps_DiIorio_Flux_Tower.kmz]