Post-Wildfire Investigation: Analysis of Soil Properties Based on Burn Severity

Science Center Objects

The Las Conchas fire started on June 26, 2011, near the small community of Las Conchas in the Jemez Mountains of north-central New Mexico. When the fire was contained on August 3, 2011, it had burned 156,593 acres of mixed conifer, pinyon/juniper and ponderosa forest and at the time was the largest wildfire in New Mexico history. Peak burn severity was extreme; over 60,000 acres of the total burned in the first 2 days.

External Links:

USGS National Research Program (NRP) 

ScienceBase Data Release

Las Conchas Fire

Las Conchas Fire

Approach

Soil-hydraulic properties examined are field-saturated hydraulic conductivity, sorptivity, and saturated volumetric water content.

  • Sample sites were randomly selected across the full spectrum (7 classes) of wildfire burn severities. Shallow soil cores were collected from these sites.
  • Hydraulic properties of the soil cores were based on tension-infiltrometer measurements in the laboratory. To minimize uncertainty, the measurements were analyzed using three separate methods.

 

Infiltration setup, Las Conchas Fire

Infiltration setup, Las Conchas Fire

Objectives

  • Assess post-wildfire impacts on hydraulic properties of soil as a function of remotely-determined burn severity.
  • Possible applications of this work include assessment for water-related hazards and other  water-resource management tasks.

 

Soil core samples collected in the Las Conchas Fire burn scar.

Soil core samples collected in the Las Conchas Fire burn scar. Top and bottom surfaces of the soil and core caps are the fourth sample from site LC–152.