Near real-time monitoring of post-fire erosion after storm events: a case study in Warrumbungle National Park, Australia

Abstract

Wildfires in national parks can lead to severe damage to property and infrastructure, and adverse impacts on the environment. This is especially pronounced if wildfires are followed by intense storms, such as the fire in Warrumbungle National Park in New South Wales, Australia, in early 2013. The aims of this study were to develop and validate a methodology to predict erosion risk at near real-time after storm events, and to provide timely information for monitoring of the extent, magnitude and impact of hillslope erosion to assist park management. We integrated weather radar-based estimates of rainfall erosivity with the revised universal soil loss equation (RUSLE) and remote sensing to predict soil loss from individual storm events after the fire. Other RUSLE factors were estimated from high resolution digital elevation models (LS factor), satellite data (C factor) and recent digital soil maps (K factor). The accuracy was assessed against field measurements at twelve soil plots across the Park and regular field survey during the 5-year period after the fire (2013–17). Automated scripts in a geographical information system have been developed to process large quantity spatial data and produce time-series erosion risk maps which show spatial and temporal changes in hillslope erosion and groundcover across the Park at near real time.

Assessment of post-wildfire erosion risk and effects on water quality in south-western Australia

“…The study by Blong et al (1982), however, concerns erosion on small plots, and scale effects (see for example Amore et al 2004 andParsons et al 2006) mean that their values are therefore likely to be higher than hillslope-scale erosion predicted by RUSLE. The range of modelled values in our study is very similar to those modelled with RUSLE (0.5-5 t ha À1 year À1 ) and measured on small plots (0.5-3 t ha À1 year À1 ) in the Warrumbungles by Yang et al (2018). In summary, it appears that the RUSLE produces reasonable predictions of hillslope erosion under unburnt conditions, but that it may underestimate erosion in areas where slopes are steep and fire severity high.…”

“…Thus, by using long-term monthly rainfall erosivity, our approach to modelling erosion with RUSLE is likely to underestimate the erosion produced in the case of an intense rainfall event. Recent developments in modelling rainfall erosivity offer opportunities for improved representation of event-based erosion rates (Yang et al 2018). Additionally, RUSLE, by its very design, does not consider connectivity between eroding hillslopes and downstream waterways.…”

Rapid Assessment of Hillslope Erosion Risk after the 2019–2020 Wildfires and Storm Events in Sydney Drinking Water Catchment

“…Soil sediment, ash, and other contaminants pose a hazard to human health when mobilized in drinking water catchments. It is therefore necessary to quantitatively estimate soil erosion after severe wildfires in order to assess the extent and magnitude of post-fire soil erosion risk and the effectiveness of any rehabilitation or mitigation actions [5].…”

Wepp Model for Rill Erosion Estimation in a Brazilian Semiarid Watershed

“…WEPP is a well-established tool to simulate water erosion and sediment yield. It has already been applied in several geographical locations such as the United States (AMPOMAH et al 2020), Australia (YANG et al 2018), andEurope (NICOSIA et al, 2019). Bezerra et al (2010) also used it to study hydraulic characteristics in preformed erosion rills in a Cambisol, in the semiarid region of Brazil, with different flow rates applied to erosion rills.…”