A fuel model classification approach for Central Europe: a high-resolution fire risk assessment example from the Czech Republic

Abstract Background Central Europe is rarely considered a high-risk region for wildfire occurrence. As climate change progresses, the likelihood of fire-conducive weather is projected to increase, which could increase wildfire frequency and severity in the region. The fuel type and amount at a given location are fundamental parameters determining the potential of vegetation cover to produce a fire of a given intensity, spread rate, and duration. In assessing the risk posed by the resulting fire, this information can be considered equivalent to the fire load concept in building design. As fires in forest and nonforest ecosystems are highly complex in terms of input parameters, fuel models have been developed as simplified representations of reality that carry vegetation-cover information in terms of burning characteristics and likely fire behavior. While the 30-m resolution fuel model classification of the USA has been available for two decades, the European reality has been much less satisfactory, with openly available data accessible at a 1-km or 100-m resolution at best. Results We developed a 30-m fuel model classification system for the Czech Republic by integrating openly available national datasets and ecological habitat descriptors to map fuel models compatible with those of Scott and Burgan (2005). The resulting maps provide a fine-grained mosaic of agricultural, successional and forest fuel types typically generalized or absent in existing European products. In FlamMap simulations under identical wind and fuel moisture settings, the Czech 30-m fuel inputs yielded substantially larger fractions with high values of the evaluated fire behavior metrics than a 100-m European product did: the proportion of cells with a spread rate > 5 m/min increased from 5.6% to 20.9%, a flame length > 2 m increased from 5.8% to 21.5%, and a fireline intensity > 1000 kW/m increased from 6.6% to 21.9%. These differences were partly explained by the contrasting treatments of agricultural fuels, with nonburnable area fractions of 15.4% in the Czech model, versus 31.3% in the pan-European product. Conclusions High-resolution fuel model mapping provides a first step to valuable tool for wildfire risk assessment and management in Central Europe. After validation process it can support preventive planning, operational decision-making, and strategic measures by land managers, conservation authorities, and fire services.