Using remote sensing data in prospection of places implying an existence of grave pits of victims of the Augustów Roundup

Abstract

To guarantee the save transport of the spoils of war from the former East Prussia to Grodno by Soviet Army the head of NKVD L. Beria have decided to eliminate the members of the Polish resistance Home Army (1939-1945) Armia Krajowa in Augustów region (Poland). The operation was carried out by the Red Army, the NKVD and the Main Directorate of Counter-Intelligence ‘SMERSH’ with the assistance of Polish officers of the Ministry of Public Security in July 1945. 592 of 7049 arrested persons who have disappeared are presumed to have been executed and buried in former Byelorussian Soviet Socialist Republic. Despite many Polish diplomatic notes issued since 1946 the location of the mass graves remained unknown. In January 2015 the Polish Institute of National Remembrance was asking the Institute of Geodesy and Cartography (IGiK) to carry out the prospection of places implying an existence of grave pits of the victims of Augustów roundup in Byelorussian and Polish parts of Augustów Forest. The goal of analysis was to test the potential of spatial data to identify the locations of places of decayed soils, implying the possibility of existence of grave pits. To achieve this goal it was necessary to complete and to process the available spatial data (i.e.: archive and recent aerial photographs, old low resolution and recent very high resolution multispectral satellite data, airborne laser scanning data), to produce detailed DTM and microrelief maps, to analyze the spatial data and to elaborate the photointerpretation key. Having this it was possible to identify the locations of places, implying the possibility of existence of grave pits and to estimate the reliability of those places by field check, as well as to extend the results of research with satellite data supervised classification. The investigations allowed to identify 4 reliable places of decayed soils, implying the possibility of existence of grave pits in Augustów, as well as 44 places of potential grave pits of transport fugitives in Polish part of Augustów forest (4 of very high probability, 5 of high probability, 4 of medium probability, 6 of low and 25 of very low probability). In Byelorussian part of Augustów forest it was possible to identify 85 places of decayed soils. Four of them near Kalety and Giedź can be (presumably) the grave pits. Fourteen objects were classified as a very probable grave pits, 21 others - as a medium probable burial places. Forty six objects were judged as low probable places of grave pits. The full list of objects with coordinates and extracts of maps, aerial and satellite orthophotomaps was included into the report submitted to the Polish Institute of National Remembrance. The control dig carried out in the case of one object in Polish part of the Augustów forest allowed to find the grave of 2 persons. The carried research have revealed, that the best results of investigations of grave pits identification can be achieved when the aerial photographs and/or satellite data acquired 4 – 5 year after the burial are available. However, it should be stressed that in the case of forest areas even analysis of remote sensing data recorded after much longer period (aerial photos after 8 years and 36 years, high and very high resolution satellite data - after 59 and 69 years, airborne laser scanning data - after 70 years) can allow to identify the objects of probable grave pits.

Received 25.09.2016 Accepted 10.11.2016 Published 30.03.2017