Genetic map of the Wielka Żuława soil cover: blanks to be filled using existing cartographic materials and remote-sensing data

Poland is considered to have a very well mapped soil cover and detailed soil cartographic materials. Despite this, some areas have “blank spots” on soil-agricultural or soil-habitat maps. These include the Wielka Żuława island on Jeziorak Lake (on the Iława Plain). This island is almost deserted and inaccessible, making detailed field research there very difficult. The aim of the work was to check the possibility of using existing cartographic materials and remote-sensing data to develop a genetic map of the soils of this area. In order to interpret the existing materials, preliminary field works were carried out: six soil pits and 22 manual drillings to an average depth of 2 m. These studies showed significant diversity of soil cover. The largest share within the central, upland part of the island have autogenous rusty soils (Brunic Arenosols according to the World Reference Base [WRB]) and clay-illuvial soils (Luvisols – WRB). The lower locations (mainly along the coast of the island) were dominated by organic soils (Histosols – WRB). The digital elevation model (DEM) enables precise determination of the boundary between THE mentioned autogenous and hydrogenic soils. In the group of organic pedons, a large area was degraded, which was expressed by the occurrence of murshic soils (Murshic Histosols – WRB). The DEM obtained from LiDAR data shows networks of (almost invisible in aerial photos) drainage ditches and channels, which turned out to be very useful in determining the extent of the mentioned degradation. The greatest difficulties concerned the extent of soil developed as a result of human influence – colluvial (Solimovic Arenosols) and anthropogenic soils. In the first case, a relief model combined with archival orthophotomosaics allowed for an approximate estimation of the places where these soils occur. Both elements (DEM and archival aerial photos) were also used to estimate the extent of occurrence of technogenic soils (Technosols – WRB).