ENVIRONMENTAL DETECTIVE: WHY DID THE TREES IN KRASNOTURANSKY PINE FOREST DIE?

Possible causes of damage to pine stands in Krasnoturansky Bor in 2022 were studied. Remote sensing data and indicators characterizing the current state of trees were used for the analysis. NDVI values of different forest areas were considered and the moment and intensity of tree damage were estimated based on these indicators. The spatial distribution of trees by the level of damage along the selected transect was studied and it was shown that the level of damage decreases linearly with increasing distance to the forest edge. Based on the results obtained, it is assumed that the cause of the damage could be a chemical burn of trees caused by herbicides when treating agricultural land near the forest edge to destroy weeds. The patterns of change in the current state of trees after impacts were studied depending on their state before damage and the state of trees before the impact on the crowns. To assess the current and retrospective states of trees, a set of indicators is proposed, including the characteristics of the spectra of the first differences in the widths of annual rings of trees in the damage zone 2-20 years before the date of damage, dielectric indicators of tree tissues, and response functions of remote characteristics of stands. It is shown that with the same visual state of trees before and after damage, their response to the impact differs significantly and some of the trees of condition category 1 according to visual features should be classified as trees with a certain level of weakening as a result of the impact. The use of a set of methods made it possible to assess the response of trees to the impact depending on their initial state before the impact.