Habitat and periphyton mapping in small forested streams via UAS

Keywords: UAS, lidar, aquatic vegetation, remote sensing
Abstract Type: Poster Abstract

Abstract

Periphyton represents a diverse assemblage of algae, fungi, bacteria, and detritus found along the benthos and has recently been shown to be a site for mercury methylation within stream ecosystems. Identifying the physical habitat factors driving periphyton distribution and abundance is crucial to understanding mercury transformation and bioaccumulation in stream systems. Remote sensing offers an opportunity to create high resolution spatial projections of periphyton habitat, distributions, and biomass. However, remote sensing of aquatic submerged vegetation and habitat in small streams can be complicated by complex bathymetry, narrow channel widths, obstructions from overhanging tree canopy cover, and the strong absorption of electromagnetic radiation from water, among others. To establish a baseline of periphyton dynamics and distribution in two mercury-impacted creeks on the Oak Ridge Reservation (ORR) in Oak Ridge, Tennessee, USA, we are conducting flyovers with unmanned aerial systems (UAS) in concert with in-situ data collection to quantify and map submerged aquatic vegetation and estimate periphyton biomass seasonally. Multi/hyperspectral and LiDAR data are being collected via UAS at high spatial to model and characterize periphyton dynamics in these two stream systems. Results are being used to further inform and prioritize ongoing research efforts at Oak Ridge National Laboratory to develop innovative technologies and approaches to remediation of mercury and methylmercury in aquatic environments. Here we’ll share results and lessons learned from our data collection events at multiple sites within these second- to fourth-order streams, and discuss potential management implications of our findings.