Analysis of the spatial distribution of the Siberian silk moth outbreak area based on terrain features in the Siberian mountain southern taiga forests

Background. The degradation of coniferous forests dominated by siberian fir (Abies sibirica Ledeb.) as a consequence of outbreaks of the Siberian silkmoth (Dendrolimus sibiricus Tschetv.) gives rise to considerable environmental and economic damage at the regional level. An improved understanding of the ecology of the pest population in mountainous terrain will facilitate the development of a more effective monitoring system and the use of a digital terrain model to predict the spread of the outbreak. This will allow the implementation of timely active forest protection measures. Purpose. This study aims to investigate the spatiotemporal patterns of the Siberian silkmoth outbreak by analyzing orographic data from mountainous southern taiga forests in Siberia. Materials and methods. The study was carried out by the method of retrospective analysis based on a geoinformation system combined with data from remote sensing of the Earth. The research was based on a time series of Landsat-8 images obtained from the USGS Earth Explorer data portal (https://earthexplorer.usgs.gov/) with a spatial resolution of 30 m. Results. This was achieved by analyzing time series data from Landsat-8 satellite images. An assessment was conducted of the area of defoliated forests and the relief features of such an area using the ASTER digital elevation model. This was done in order to detail the parameters for predicting the development of the pest outbreaks based on the following orographic characteristics in mid-mountain relief: height above sea level, terrain slope and slope exposure. Conclusion. It is recommended that the early detection of Siberian silkmoth outbreaks in mountainous southern taiga forests should be aimed at the initial monitoring of dark coniferous stands concentrated at altitudes from 400 to 600 m above sea level, located on flat areas and slopes of up to 15 degrees, including exposures predominantly occupied by feather moss forest types. EDN: XLRKHE