Abstract: The workshop will present the results of a study funded by the EPA on a method to monitor wetland vegetation type, extent of plant cover and plant vigor using remote sensing images. This method is far less labor intensive and offers more accurate and reliable information which is urgently needed by managers and agencies responsible for coastal wetland integrity and reporting, and its low cost makes it sustainable over long periods of time.
The method utilizes remote sensors and digital images from airplanes and tethered balloons that capture detailed views of wetland vegetation. These images are processed to separate and map wetland plant species and to detect areas under stress. Changes in canopy texture are used as a surrogate for sediment chemical conditions. From the analysis of these images it is possible to know the composition and extent of wetland vegetation and anomalies in the sediments that may be responsible for putting stress on plant communities.
This study verified findings from past research by demonstrating the ability of remote sensors (i.e. hyperspectral, LIDAR and balloon photography) to map plant composition and its extent at a resolution of eight feet to a few inches and revealed new relationships between canopy texture and plant height with prevailing biogeochemical conditions in the sediments. Sediment field measurements were used to calibrate the image models where salinity, oxidation reduction potential and sulfide concentration in the rizoshpere explain most of the variation in plant height and canopy texture.