Forest Fires as a Soil Contamination Driver

Trabajo presentado en el 1st World Conference on Soil and Water Conservation under Global Change (CONSOWA), celebrado en Lleida del 12 al 16 de junio de 2017According to the International Panel on Climate Change, there is higher degree of confidence that meteorological conditions associated to climate change will be propitious to increasing extreme events (IPCC, 2014). Impacts on land degradation will be shown in bigger and more frequent wildfires. One aspect of fire-induced ecosystem degradation that has drawn scientific interest recently is the chemical pollution related to forest fires. This contamination is associated either to the use of chemicals to their extinction known as flame retardants, FRs (Pepper et al., 2011), or because incomplete combustion of vegetation favours the formation of polycyclic aromatic hydrocarbons, PAHs (Yuan et al., 2008). Brominated flame retardants account for a large group of FRs used for firefighting. Polybrominated diphenyl ethers (PBDEs) are the second highest production group of BFRs, and their presence has been reported in sediment and soil (Akortia et al., 2017). Some researchers have already studied the PAH production in relation to forest fires finding a significant increase in soil, but not so much as to reach harmful levels (Choi, 2014). It has been found that compounds such as BFRs and PAHs are persistent, bio-accumulative and/or toxic to wildlife and humans, as well as potential endocrine disruptors (Eulaers et al., 2014). Consequently, the production and use of the most common PBDEs, penta- octa- and deca-BDE, is nowadays highly restricted after regulations that were introduced by USA and EU, and have been included as Persistent Organic Pollutants in the Stockholm Convention (UNEP, 2010). The hypotheses of the study are that the fire occurred, in 2014, in Azuébar, Castellón (Spain) added significant amounts of emerging contaminants to the soil, and that these concentrations are a function of the position on the hillslope, the soil depth and the presence of vegetation. It is also hypothesized that contaminants are transported downslope with increasing levels in the eroded sediment.Peer reviewe