The work of conducting environmental surveys and assessments can be tough and physically taxing, involving pushing into areas that are difficult to access. And this kind of boots-on-the-ground labor will likely always be a part of this business. But technology is also changing the way we do things, and this is nowhere more evident than with recent use of drones to conduct surveys in Umpqua National Forest. These drone flights, conducted in collaboration with the U. S. Forest Service by GBI Soils and Hydrology Specialist, Zach Meyer, were part of a mid-level assessment, spatially quantifying post fire effects and possible interventions. Here Zach provides an overview of the now-concluded drone flights, along with this spectacular screenshot of a belted kingfisher that came within a few feet of the drone camera.
“The assessment we conducted was on approximately 200,000 acres of fire footprint that occurred over the past four years on the Umpqua National Forest. In order to efficiently access enough stream systems to be able to speak to the large picture as well as the local specific cases, the team chose to use a drone or a UAS to accomplish efficient stream mile access. The drone additionally increased the relative safety of the team that would otherwise be bushwhacking through inhospitable terrain. There is always a strong need to assess the status of creeks within the watershed of burned areas. Post-fire erosion, tree mortality, stream shade, and large woody debris structures often undergo major changes. Large log jams are often lost that normally act as sediment and gravel storage, stream bank stabilizers, reduce stream velocity, and therefore channel scour through the increased degree of surface roughness.
“To conduct an assessment of a data point, the drone is flown over a creek and then raised and lowered while the camera moves around in all directions taking video footage. The video is later analyzed to determine the percent loss of canopy cover, and any signs of excessive erosion. Topography is also considered as a variable affecting stream shade. The footage is used to look for large wood quantities within the channel as well. Several other factors are described such as approximate distance to the nearest live conifer as a natural source of seed dispersal and reforestation. The post fire vegetation response is also characterized as well in order to inform the USFS of areas that are exhibiting natural recovery or regeneration signs, or on the contrary areas that are possibly in need of some treatment to assist in the restoration of the forest in a given location.
“One additional expected product from the drone is the provision of a public outreach video that captures footage conveying the current status and needs of forest restoration on the Umpqua National Forest in relatable context for the public.”
