Gray Turnage is looking forward to the day when he no longer has to trudge through mud to do coastal wetland research. Turnage is an invasive species expert with Mississippi State University and was recently part of a team that used a drone to map a species of wetland plant. The drone allowed researchers to get better images than from a satellite, cut down on the cost of plotting the plants by hand and spend less time in the mud.
“For me, I think it gives us as resource managers a new tool to do our jobs,” Turnage said. “If I never have to hike into a marsh again that would be nice.”
The Mississippi State research team programmed a drone carrying a digital SLR camera to fly over the lower Pearl River basin, near the border of Mississippi and Louisiana. As the camera took pictures, the drone tracked the latitude, longitude and altitude at which each picture was taken.
Sathish Samiappan, a Mississippi State Geosystems Research Institute postdoctoral associate, wrote software to tell a computer system the color, texture and shape of a species of wetland plant. The system was then able to locate the plant within the images. The team stitched those images together to create a map showing where the plant was growing within the delta.
Traditionally, researchers have mapped wetland plants using satellite imagery, by using photos taken from a plane or by walking though marshland with a GPS. But satellite imagery typically has low resolution, making it difficult for researchers to identify plants. Satellites may only orbit over a given location once every two months, making it hard to track changes in the landscape.
While images taken from a plane have better resolution than from a satellite, hiring a pilot and plane is costly. Walking an area with a GPS also has its disadvantages. It’s time intensive and can expose researchers to dangers, such as insect-borne diseases.
A drone, on the other hand, is less time intensive, more affordable and safer for researchers — even as they have to keep the drone within eyesight. “Being able to sit offshore with a boat is a very comforting thought,” Turnage said.