Sapelo Research Application Form
Research Application ID: GCE-126-2022 (submitted: 10/03/2022, status: approved)
Provide a brief title for web display
Disturbance across the salinity gradient
Investigator Information
On Island Sponsor: GCE SINERR UGAMI GADNR
| Principal Investigator: | Steven C. Pennings | ||
| Home Institution: | University of Houston | ||
| Award Information: | GCE-LTER main award | ||
| Mailing Address: | Department of Biology and Biochemistry | Phone Number: | (713) 743-2989 |
| University of Houston | E-mail Address: | scpennin@central.uh.edu | |
| Houston, Texas 77204-5513 | |||
| Co-investigators: | |||
Briefly describe the project goals and methodology
Our goal is to understand how intertidal marshes recover from disturbance, with a focus on whether recovery rates vary as a function of porewater salinity. We hypothesize that plants at high salinities relative to the tolerance of that species will recovery more slowly than plants at lower salinities. To ensure that our results are general, we will test this hypothesis using four plant communities, from fresh to saline: 1) Zizaniopsis, 2) Juncus roemerianus, 3) Spartina alterniflora, and 4) mixed succulents.
For each species, we will set up 15-20 pairs of plots, spanning the entire salinity gradient where this species occurs. The location and elevation of each plot will be measured with RTK GPS. The total number of plots that might be deployed is 160 (20 pairs x 4 vegetation types).
Each pair will consist of a disturbed and a control plot. The disturbed plot will be trampled and covered with a plastic tarp (4 x 6 feet) for about 3 months to kill the underlying vegetation. Tarps will be staked to the ground with multiple pvc poles inserted at an angle to hold the tarp securely. A previous experiment with this method on Sapelo Island successfully deployed 19 tarps with no losses.
Once the underlying vegetation is dead, tarps will be removed. We will deploy a 0.5 x 0.5 m plot in the disturbed area (corners marked with pvc poles) and a paired plot in an adjacent undisturbed control area. Plots will then be monitored several times per year to document recovery of vegetation and soils.
Where will the project be located?
See attached map for general locations. I will contact property managers for permission.
How will you provide GPS coordinates for study sites?
I will provide a provisional map and arrange with my sponsor to collect and register GPS coordinates
What are the expected start and end dates of the project?
Start Date: 03/01/2023 End Date: (ongoing)
How many people will access the site and at what frequency?
Three people will access each plot four or five times per year.
Keywords that describe your project
What equipment will be deployed in the field?
Each plot will be marked with 3/4 inch pvc stakes. During the initial disturbance treatment, plots will be temporarily covered with tarps for 2-3 months to create the disturbance. Tarps will then be removed and we will watch the vegetation recover.
Will plants or animals be collected as part of this study?
No collections.
What are the likely impacts of the project on the site?
The experiment simulates wrack disturbance, which is common in coastal salt marshes. We expect, based on past observations that vegetation will recover to control conditions in 2-4 years in Spartina, succulent and Zizaniopsis marshes. Juncus marshes may take longer to recover, which would be an important finding of the project.
Will the project design include boardwalks? If not, explain why not.
No, because visits will be infrequent and plots widely separated.
How long will impacts persist after the research is concluded?
We will monitor the plots until the effects of disturbance are no longer apparent, likely 2-4 years for most plots, but somewhat longer for Juncus plots.
Research Permits:
Georgia DNR Coastal Resources Division: GCE-126-2022_Permit_RLS20220051_Pennings_Disturbance_signed (01/24/2023-01/29/2028)
Site Photographs:
Files attached to this application
GCE-126-2022_Maps_Map_1_for_GCE.pdf (PDF file, 159.88 kb, submitted 10/03/2022)
GCE-126-2022_Photos_IMG_2942.JPG (Jpeg image, 9859.56 kb, submitted 10/03/2022)
