Applied Remote Sensing in the Middle Rio Grande
Chris Sanderson1*, Ondrea Hummel1
1 Tetra Tech, Albuquerque, NM, USA; ondrea.hummel@tetratech.com, chris.sanderson@tetratech.com
Riparian ecosystem disturbance occurring at broad temporal and spatial scales must be examined on a landscape-scale to evaluate the magnitude and character change. Over the past century the overall quality of riparian habitats in the Middle Rio Grande have been negatively impacted by several anthropogenic factors and more recently by the introduction of the tamarisk leaf beetle (Diorhabda spp., TLB) as a biological control agent to suppress tamarisk (Tamarix spp.). Ongoing TLB defoliation has resulted in reduced vegetative cover and novel fire behavior in riparian areas, which has negatively impacted Southwestern Willow Flycatcher (Empidonax traillii extimus) (flycatcher) breeding and nesting habitat.
The use of remote sensing (RS) and vegetation indices is ideally suited to monitor landscape-scale ecosystem change related to the photosynthetic process and primary production, growth patterns, and the extent and severity of fire events. For example, the range and timing of Diorhabda defoliation or the extent and severity of fire is difficult to track and analyze from the ground but can be rapidly and repeatably characterized using RS techniques. We will present RS methods using Sentinel-2A, a moderate resolution earth observation data, and several RS outputs used to support field-based monitoring practices and habitat restoration analysis and planning. These methods have been developed to characterize target areas, understand spatial patterning and their underlying processes, prioritize field efforts, and quantify vegetation change over time.
In the first case study, we will present RS techniques used to monitor tamarisk-dominated stands over a 3-year period, during which TLB became an established disturbance agent. The second case study will describe examples of RS techniques used to support post-fire habitat restoration planning in a 9,000-acre riparian context. Examples of burn area mapping and ground verification techniques using RS will be presented.