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USGS · 70237131

Landscape change, fire and erosion

Abstract

New Mexico has a dynamic landscape, which will become even more so in response to climate change over the next 50 years, in part because of increasing incidence of wildfire. As the climate changes to warmer conditions, less rainfall will infiltrate into aquifers, leading to increased overland runoff. Landform processes can be complex, but in general, the predicted changes in climate and precipitation will lead to increased flooding, increased upland erosion caused by runoff, and increased downstream sediment deposition. Canyons and mesas, small basins or valleys filled with sediment will be particularly affected. Rapid rearrangement of sediments by water is disruptive and potentially hazardous to ecosystems and societies. Dramatic examples of accelerated erosion following the Whitewater-Baldy, Las Conchas and other wildfires here in New Mexico illustrate the types of hazards created when forested landscapes are severely burned. Post-wildfire erosion is typically initiated by intense rainfall events. Given that both the number of wildfires, and rainfall intensities are likely to increase as the climate warms, New Mexico can expect to see increases in widespread erosion and sedimentation across and downstream from upland forested areas in the state. The large volume of sediment predicted to be on the move will be of concern for many reasons including filling reservoirs, choking channels, blocking or destroying infrastructure and positive feedback loops that lead to further reductions in slope stability.

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90° N90° S · 180° W ← longitude → 180° E
Source-reported bounding extent: 31.332301° to 37.000232° latitude; -109.050173° to -103.001964° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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BibTeXRIS

Anne C. Tillery, Leslie D. McFadden, Craig Allen. 2022. Landscape change, fire and erosion. https://pubs.usgs.gov/publication/70237131

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Virginia