Skip to Main Content
The legacy of a severe wildfire on stream nitrogen and carbon in headwater catchmentsAuthor(s): Charles C. Rhoades; Alex T. Chow; Timothy P. Covino; Timothy S. Fegel; Derek N. Pierson; Allison E. Rhea
Source: Ecosystems. 22: 643-657.
Publication Series: Scientific Journal (JRNL)
Station: Rocky Mountain Research Station
Download Publication (720.0 KB)
Related Research Highlights
Severe Wildfire Has Long-term Consequences for Stream Water Quality
DescriptionLarge, high-severity wildfires alter the physical and biological conditions that determine how catchments retain and release nutrients and regulate streamwater quality. The short-term water quality impacts of severe wildfire are often dramatic, but the longer-term responses may better reflect terrestrial and aquatic ecosystem recovery. We followed streamwater chemistry for 14 years after the largest fire in recorded Colorado history, the 2002 Hayman Fire, to characterize patterns in nitrogen (N) and carbon (C) export. Throughout the postfire period, stream nitrate and total dissolved N (TDN) remained elevated in 10 burned catchments relative to pre-burn periods and 4 unburned control catchments. Both the extent of fire in a catchment and wildfire severity influenced stream N concentrations. Nitrate was more than an order of magnitude higher in streams draining catchments that burned to a high extent (> 60% of their areas) compared to unburned catchments. Unburned catchments retained more than 95% of atmospheric N inputs, but N retention in burned catchments was less than half of N inputs. Unlike N, stream C was elevated in catchments that burned to a lesser extent (30-60% of their areas burned), compared to either unburned or extensively burned catchments. Remotely sensed estimates of upland and riparian vegetation cover suggest that burned forests could require several more decades before forest cover and nutrient demand return to pre-fire levels. The persistent stream N increases we report are below drinking water thresholds, but exceed ecoregional reference concentrations for healthy stream ecosystems and indicate that extensively burned headwater catchments no longer function as strong sinks for atmospheric N. Combined with increasing trends in wildfire severity and elevated N deposition, our findings demonstrate the potential for substantial post-wildfire changes in ecosystem N retention and have implications for nutrient export to downstream waters.
- You may send email to firstname.lastname@example.org to request a hard copy of this publication.
- (Please specify exactly which publication you are requesting and your mailing address.)
- We recommend that you also print this page and attach it to the printout of the article, to retain the full citation information.
- This article was written and prepared by U.S. Government employees on official time, and is therefore in the public domain.
CitationRhoades, Charles C.; Chow, Alex T.; Covino, Timothy P.; Fegel, Timothy S.; Pierson, Derek N.; Rhea, Allison E. 2019. The legacy of a severe wildfire on stream nitrogen and carbon in headwater catchments. Ecosystems. 22: 643-657.
Keywordswatershed biogeochemistry, forest disturbance, nitrogen cycling, streamwater nutrients, dissolved organic carbon, Colorado, nutrient retention, wildfire severity, Ponderosa pine forest
- The influence of wildfire extent and severity on streamwater chemistry, sediment and temperature following the Hayman Fire, Colorado
- Impact of wildfire on stream nutrient chemistry and ecosystem metabolism in boreal forest catchments of interior Alaska
- Soil pCO2, soil respiration, and root activity in CO2 - fumigated and nitrogen-fertilized ponderosa pine
XML: View XML