View Document


Characterizing the Effects of a Prescribed Fire on Sediment and Phosphorus Biogeochemistry in a Montane Intermittent Stream
Department: Geology
ResourceLengthWidthThickness
Paper000
Specimen Elements
Pocatello
Unknown to Unknown
Jennings H. Leavell
Idaho State University
Thesis
Yes
9/23/2026
digital
City: Pocatello
Master
Phosphorus chemical forms are likely to vary with fire and stream drying, yet phosphorus dynamics in burned, intermittent stream systems are understudied due to the episodic nature of these disturbances. Here, we measured bed sediment, suspended particulate, and dissolved phosphorus concentrations; performed X-ray absorption near edge structure spectroscopy (XANES); and performed supporting bed sediment biogeochemistry analyses to examine phosphorus dynamics in response to seasonal drying and a prescribed fire in an intermittent stream. We hypothesized that suspended sediments, inorganic phosphorus forms in sediments, and soluble reactive phosphorus (SRP) in the water column would increase immediately following a prescribed fire, but be delayed in transport with stream rewetting. We found that total suspended sediment (TSS) concentrations increased significantly from pre- to post-fire medians (Q1 to Q3), 0.79 (0.0094 to 2.9) to 663.58 (323.98 – 817.56; p = 1.67 x 10-6, F2,30 = 21.42). However, total sediment yields were not significantly higher than yields from similar water years likely owing to the low-moderate severity fire. While significant changes in sediment phosphorus concentrations were not observed, soluble reactive phosphorus increased significantly during an immediate post-fire rewetting event. XANES analyses showed a spatially variable mix of inorganic- and organic-associated phosphorus forms in bed sediments prior to burn shifted towards more inorganic forms, an average decrease of 12.9 %. We conclude that a prescribed fire can impact a stream’s TSS but not alter sediment composition and phosphorus bonding when the severity and extent of fire is low-moderate and does not burn the predominantly dry channel bed. Keywords: phosphorus, prescribed fire, suspended sediment, intermittent stream, Reynolds Creek

Characterizing the Effects of a Prescribed Fire on Sediment and Phosphorus Biogeochemistry in a Montane Intermittent Stream

Necessary Documents

Paper

Document

Information
Paper -Document

2008 - 2016 Informatics Research Institute (IRI)
Version 0.6.1.5 | beta | 6 April 2016

Other Projects