St. George Island Dune Vegetation Census

Methods

Six permanent vegetation grids were established at the eastern tip of St. George Island in 1998: 2 grids each in the foredune, interdune and backdune areas. Each grid is 60 x 60 m and contains a 7 x 7 array of plots, with each plot separated by 10 m, for a total of 294 individual plots covering almost 2.5 hectares. The site is in St. George Island State Park where research permits have been re-issued to T. Miller by the Florida Department of Environmental Protection to work on a variety of projects since 1992.

Since 1999, 10-15 graduate students and faculty volunteers from Florida State University have helped to census the 294 plots. Census teams consist of several data collectors and at least one botanist to insure accuracy and consistency. A 1-m2 quadrat is placed over each plot and all vegetation is counted by # individuals, # clumps, and/or % cover by species. Each group uses standardized plant keys that are updated each year. Any unknown plants are sampled off the plots in replicate, given an ID number and identified later. Other aspects of each plot are also noted, such as dead plants or evidence of flooding or sand movement.

We also collected data on some environmental variables associated with each plot. Gravimetric percent soil moisture was determined in 1999 by collecting a 2 cm diameter x 15 cm column of sand from a corner of each plot. Each sample was placed in an airtight bag, and later weighed, dried at 60°C, and re-weighed to determine percent soil moisture. Percent ash was determined using the same samples and reweighing the samples after being heated in a combustion furnace. The elevation of each plot relative to mean sea level was determined in 2007 using a TopCon Total Station.

Climate records have been obtained from Apalachicola, FL, providing data on weather and precipitation (National Estuarine Research Reserve System) and storm surge (NOAA).

St. George Island Dune Vegetation Census Homepage

Species List

Census Data

Publications

Revised August 24, 2011