Complex morphometric evaluation of a Jewish Autonomous Region relief by means of geographic information systems

Relevance. The relief is the basis for landscape, landscape-geochemical, soil and plant association studies, soil erosion, etc. Aim. Evaluation of the erosion hazard of the relief of the Jewish Autonomous Region. Object. Relief of the Jewish Autonomous Region. Methods. The relief was estimated on the basis of SRTM with a raster cell size of 90×90 m. Several images were combined into one with subsequent framing of the final layer by mask to highlight the study area. To calculate a complex morphometric indicator and assess the erosion hazard of the relief, a vector polygonal layer with a cell size of 1×1 km was created. Median values of surface slopes, slope exposures, maximum and minimum absolute heights for each polygonal cell were extracted directly from the digital relief model. The vertical dissection of the relief is calculated as the difference between the maximum and minimum elevation of the relief above sea level. To identify the spatial differentiation of erosion, the horizontal dissection of the relief was calculated, i. e. the length of the erosion network in km per 1 km2 of the territory. A hydrological correction of the digital relief model was made and the hydro grid was restored. Using the operation "sum of distances in polygons", the values of the length of the erosion network for each polygon cell with an area of 1 km2 are calculated. The parameters of all layers are summarized in a single table, they are assigned a score, depending on the value of the indicator. The complex indicator is calculated as the sum of the scores of all indicators. Results. The author has constructed the estimated map of the erosion hazard of the relief of the Jewish Autonomous Region. It was found that a low value of erosion hazard is typical for 88.56% of the region territory, the average for 11.42%, and the share of the territory with a high value of erosion hazard is only 0.02%.