RAPID: Ecosystem-level responses along the mainstem of Lookout Creek after a major wildfire

Oregon State University, Corvallis OR

Investigators

Abstract

This project will investigate how Lookout Creek, Oregon, was affected by the Lookout Fire that occurred from August to October 2023. The researchers aim to understand the changes in stream ecosystem structure and function, focusing on microbial decomposition, aquatic vertebrates, and riparian wildlife. This research will advance scientific knowledge because it sheds light on how wildfires impact ecosystems, particularly in forested watersheds like Lookout Creek. By testing alternative hypotheses, researchers gain insights into how both the stream and wildlife in the surrounding forest might change after a major wildfire. The study will help scientists predict and manage the aftermath of similar wildfires in the future, informing land management practices and conservation efforts to understand post-fire ecosystem recovery. This project will provide experiential learning opportunities for a wide range of graduate and undergraduate students, especially those from diverse backgrounds who are underrepresented in STEM. The inclusion of students from diverse backgrounds will contribute to a more diverse workforce that will ultimately strengthen innovation and problem-solving on issues related to wildfires and freshwaters. Studying post-fire changes in biodiversity has broader societal impacts as wildfires have significant economic and social implications affecting clean water, air quality regulation, and recreational opportunities. Three hypotheses will be tested by examining the stream and riparian zone after this extreme fire, compared to prior conditions. The cumulative effect suggests the effects of the fire will accumulate downstream whereas the diluted effect hypothesis posits that downstream sites will buffer the effects from the fire. The stream resilience hypothesis proposes faster recovery in areas with high fire severity due to habitat heterogeneity. The researchers will assess microbial decomposition rates in riparian soils and streams using similar pre- and post-fire methodologies. A cotton strip assay placed in different locations will measure decomposition rates, with strips deployed for two to three weeks and analyzed for changes in dissolved oxygen concentrations. Electrofishing will be conducted during low streamflow conditions to capture the abundance and size of fish and salamanders. Gastric lavage will be used to assess diet composition, prey richness and diet overlap between fish and salamanders pre- and post-fire. Motion-sensor camera traps will monitor terrestrial vertebrate biodiversity, recording behavior and species identification. This project will provide experiential learning opportunities for a wide range of graduate and undergraduate students, especially those from diverse backgrounds who are underrepresented in STEM. Collectively, findings from this research will help managers and decision-makers be better informed as they create climate- and fire-smart management plans in the era of changing climate and increasing wildfires. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.