Loss in CO2 assimilation by forest stands relative to its emissions generated by the economic sector as an indicator of ecological consequences of a windstorm in the municipality of Brusy, NW Poland

The extent of damage to state and private forests as well as roadside and field buffer strips of trees in the urban-rural municipality of Brusy in the Pomerania Province, Poland, following the powerful windstorm on 11–12 August 2017, was calculated based on different data. The size of losses was expressed in m3 of large (merchantable) timber harvested from windsnap or windthrow. The biomass of the destroyed assimilation apparatus was estimated using expansion factors and ratios of individual compartments of damaged trees representing 20 species. By applying conversion factors expressing the amount of carbon dioxide fixed during the year per unit of dry leaf biomass of each tree species, the total loss in net and gross photosynthesis, corresponding to the biomass of the destroyed assimilation apparatus, was estimated. The obtained values were compared with CO2 emissions generated by the commune in 2006, 2013 and 2020. It has been found that the sum of losses in photosynthesis and CO2 emissions generated by economic activity is a good indicator of environmental threats, and the percentage of losses accounted for by photosynthesis is a good indicator of ecological losses caused by the windstorm in the forest stands.