TEMPERATURE PATTERNS IN SMALL STREAMS FOLLOWING WILDFIRE

We examined the influence of a moderately severe wildfire on the therm al patterns in three small streams in central Idaho, USA, for an 11-mo nth period beginning ten months after the fire. Two streams in unburne d catchments served as reference sites. No differences were observed b etween the burned and reference streams in daily minimum temperatures or in the general thermal conditions during winter. During late summer and early autumn, when solar radiation was greatest, the burned strea ms displayed warmer temperatures than did the reference streams. Durin g non-winter months, the burned streams experienced diel ranges in wat er temperature 2-3x greater than those of the reference streams. Despi te these differences, the number of degree-days accumulated among the streams was similar. In general, the wildfire altered the thermal stab ility of the burned streams, relative to the reference streams. Return to a pre-fire condition is expected to occur as riparian vegetation ( shading) recovers along the burned streams.