Biologists and geographic information system specialists from the Grand Bay National Estuarine Research Reserve (GBNERR), along with the U.S. Forestry Service, are using unmanned aircraft systems (UAS) from Mississippi State University’s Geosystems Research Institute (GRI) to survey and capture imagery of the after-burn of more than 4,200 acres in the Grand Bay National Wildlife Refuge and adjacent lands.
The remote marsh and woodlands habitat recently burned as a result of a large wildfire that spread across southeast Jackson County into Alabama. According to GRI, the UAS were able to capture imagery within a few hours.
Lindsay Spurrier, a geographic information specialist with GBNERR, says that before they used UAS to learn about the importance of fire to restore habitats, their studies were limited by imperfect evidence.
“A crew of field biologists would spend weeks trying to hike to remote spots within the upland pines and across the marsh to gather enough data to get a good sample of vegetation post burn,” says Spurrier. “The imagery taken from the unmanned aerial vehicles gives us, in almost real time, the changes in the trees and vegetation, along with showing the density and re-growth.”
GRI says the Altavian Nova Block III scanned the area at 1,000 feet and used a MicaSense RedEdge five-band sensor device to capture the biodiversity of vegetation health and, in precise detail, the areas of upland and marsh that burned.
“The MicaSense RedEdge is a multispectral sensor,” says Robert Moorhead, director of GRI. “It can sense energy at five different wavelengths, with two of those wavelengths beyond our own vision in the near infrared (NIR) region of the electromagnetic spectrum.”
“NIR is great for studying the status of the living vegetation,” adds Louis Wasson, GRI remote sensing expert. “Researchers no longer have to guess about the status of biodiversity restoration. The multispectral sensor provides precise data that gives researchers the status of vegetation extent and the areas under stress in the coastal ecosystem.”
According to GRI, UAS are becoming an increasingly popular tool for land managers and researchers because it gives them easy access to the land they manage.
“It is important because it can show us where there are dense, thick stands of trees that compete with new plants for water and nutrients,” says Spurrier. “These mosaicked images help us determine where to conduct prescription burning to create an opening to let more light filter in and spur new vegetation growth.”