Modelling surface runoff to evaluate the effects of wildfires in multiple semi‐arid, shrubland‐dominated catchments

Abstract

Abstract:Wildfires change the infiltration properties of soil, reduce the amount of interception and result in increased runoff. A wildfire at Northeast Attica, Central Greece, in August 2009, destroyed approximately one third of a study area consisting of a mixture of shrublands, pastures and pines. The present study simultaneously models multiple semi-arid, shrubland-dominated Mediterranean catchments and assesses the hydrological response (mean annual and monthly runoff and runoff coefficients) during the first few years following wildfires. A physically based, hydrological model (MIKE SHE) was chosen. Calibration and validation results of mean monthly discharge presented very good agreement with the observed data for the pre-wildfire and postwildfire period for two subcatchments (Nash-Sutcliffe Efficiency coefficient of 79.7%). The model was then used to assess the pre-wildfire and post-wildfire runoff responses for each of seven catchments in the study area. Mean annual surface runoff increased for the first year and after the second year following the wildfires increased by 112% and 166%, respectively. These values are within the range observed in similar cases of monitored sites. This modelling approach may provide a way of prioritizing catchment selection with respect to post-fire remediation activities. Additionally, this modelling assessment methodology would be valuable to other semi-arid areas because it provides an important means for comprehensively assessing post-wildfire response over large regions and therefore attempts to address some of the scaled issues in the specific literature field of research.

Synthesising empirical results to improve predictions of post-wildfire runoff and erosion response

“…Both these papers join an increasing body of literature (e.g. Miller et al 2011;Rulli et al 2013;Moussoulis et al 2015;Notario del Pino and Ruiz-Gallardo 2015) demonstrating the value of adopting a modelling approach in post-wildfire erosion and hydrology research.…”

Afforestation, Subsequent Forest Fires and Provision of Hydrological Services: A Model‐Based Analysis for a Mediterranean Mountainous Catchment

“…However, recent studies have provided solutions, such as fire-adapted algorithms (Nunes et al, 2016c;Vieira et al, 2014) or methods to parameterize postfire vegetation and soil properties in existing models (Fernández & Vega, 2016;van Eck et al, 2016). Models can now be used to evaluate the specific impacts of wildfires, separating them from postfire weather or catchment physiographic characteristics (Morrison & Kolden, 2015;Moussoulis et al, 2015) and can therefore establish the long-term impacts of fires on soils and streams in different environments.…”

Physically‐Based Modelling of the Post‐Fire Runoff Response of a Forest Catchment in Central Portugal: Using Field versus Remote Sensing Based Estimates of Vegetation Recovery

“…Studies applying continuous models to Mediterranean burnt areas have pointed to the importance, for adequate runoff simulations, of representing vegetation destruction and recovery (Soto & Díaz‐Fierros, ; Morrison & Kolden, ; Moussoulis et al ., ) and soil water repellency (Esteves et al ., ; Vieira et al ., ). For predictions during individual large storms, Chen et al .…”

“…Studies applying continuous models to Mediterranean burnt areas have pointed to the importance, for adequate runoff simulations, of representing vegetation destruction and recovery (Soto & Díaz-Fierros, 1998;Morrison & Kolden, 2015;Moussoulis et al, 2015) and soil water repellency (Esteves et al, 2012;Vieira et al, 2014). For predictions during individual large storms, Chen et al (2013) have shown the importance of simulating the transition between saturation-excess to infiltration-excess runoff generation, which could also reflect repellency conditions; few studies have focused on vegetation recovery at this scale.…”