Burning Trash for Science: The Potential Use of Discarded Waste to Monitor Energy Fluxes Delivered to Ecosystem Components by Wildfires

Assessing the energy flux delivered to ecosystem components by wildfires is hard because of technical and safety problems in performing measurements during such events. Here, we present a laboratory and field experimental assessment of a new method of evaluating a wildfire energy flux; our approach is based on the fact that different types of trash deform at different temperatures. We produced deformed trash in a laboratory environment using an iCone calorimeter to deliver a range of heat fluxes over a range of durations. We followed this by placing trash in instrumented prescribed fires. We show that finding melted or heat-altered plastic bottles and aluminium cans in the aftermath of wildfires can provide useful information about the heating that they received during the fire: plastic bottles are a useful indicator for areas that received less than 2 MJ/m2 with a maximal temperature of <200 °C, while aluminium cans may be applied to higher-energy sites 100 MJ/m2 that experienced a temperature above 600 °C. We provide a semi-quantitative proxy guide as to what different observed deformations may indicate in terms of energy flux and hope that this may allow scientists and forest managers to easily and cheaply assess the energy flux delivered to ecosystems and semi-quantitatively compare different wildfires.