Rodeo-Chediski Wildfire's Impacts on Southwestern Ponderosa Pine Ecosystems, Hydrology, and Fuels, 2002

摘要

The Rodeo-Chediski Wildfire burned nearly 462,600 acres in north-central Arizona in the summer of 2002. The wildfire damaged or destroyed ecosystem resources and disrupted the hydrologic functioning within the impacted ponderosa pine (Pinus ponderosa) forests in a largely mosaic pattern. Impacts of the wildfire on ecosystem resources, factors important to hydrologic functioning, peak stormflow events and water quality constituents, and loadings of flammable fuels were evaluated on two watersheds in a ponderosa pine forest that was exposed to the burn-one experienced a high severity (stand-replacing) fire (Watershed A), and the other was exposed to only a low severity (stand-modifying) fire (Watershed B). Cumulative impacts of the wildfire on ecosystem resources, hydrologic functioning, and flammable fuels were more pronounced on Watershed A. Recovery of the Stermer Ridge watersheds from the Rodeo-Chediski Wildfire has been related to the respective fire severities that the two watersheds experienced. Watershed A converted from ponderosa pine to grasses, forbs, and a few shrubs. Recovery of the hydrologic functioning on this watershed has begun on a limited scale, but it is anticipated that the overall hydrologic functioning of Watershed A will not approach pre-fire conditions for many years. Flammable fuels represented by standing trees have been eliminated on Watershed A, but there has been an increase in stem sections, branches, twigs, and herbaceous fuels on the forest floor. While the possibility of a future crown fire has declined, the potential for surface fire remains. Much of Watershed B is slowly recovering from the impacts of the wildfire. Much of the hydrologic functioning of this watershed is also returning slowly to its pre-fire level. The post-fire loadings of flammable fuels were largely unchanged from their pre-fire estimates. Watershed B remains vulnerable to future wildfire events as a consequence.