Geobotanical indication of the drained state of disturbed peatlands for fire hazard assessment

The issue of fire hazard in abandoned peatlands is particularly relevant nowadays, as the negative consequences of peatland fires lead to deterioration in public health and the functioning of the entire infrastructure system. The problem of predicting and assessing peat burning is a global one, with numerous studies being conducted not only in Russia but also abroad, i. e., in CIS countries, Southeast Asia, Canada, and the United States. However, the relationship between vegetation communities and the frequency of fires receives insufficient attention. The study is devoted to assessing the condition of degraded peatlands using geobotanical indicators of peat soils on the example of peatlands in Leningrad and Pskov regions. Three key objects were selected, which represent abandoned peat deposits. The methodology for assessing the fire hazard of peatlands is based on a comprehensive approach, including the creation of large-scale vegetation maps using a series of satellite images and field geobotanical descriptions, and the analysis of fires on objects for the period from 2000 to 2023 using satellite images and thermal data. As a result of the study, maps of fire frequency and duration and maps of natural-territorial complexes for each plot were obtained. The analysis of the relationship between vegetation communities and the frequency of fires showed that the species composition of the communities correlates relatively well with the time elapsed since the date of the last fire, and to a lesser extent with the duration of the fires. Indicative relationships between fire frequency and vegetation cover are quite strong, so the type of vegetation cover can be used as an indicator of fire frequency on a peatland. On territories with peat bogs with a sparse birch forest, fire occurs at least once every 5 years. On territories with sphagnum associations and reed swamp associations, fire occurs no more than once every 20 years.