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In 2011 the Marshal Office of Malopolska Voivodeship decide to evaluate the vulnerability of soils to water erosion for the entire region. The special work-flow of geoinformation technologies was used to fulfil this goal. First of all, the soil map had to be updated to include changes in land use and land cover which took place since 1960s, when most of them were made. The process of soil map updating had to be realised with very high degree of automation, because of the large area to be mapped (ca. 15 000 km sq.) and limited time period (ca. 3 months for complete erosion risk assessment). The approach used was based on the Object Based Image Analysis (OBIA) of orthophotomaps from both high resolution satellite images (RapidEye) and digital aerial photographs and applied GIS spatial analyses. Soil map with up-to-date land use and land cover information, together with rainfall data, detailed Digital Elevation Model and statistical information about areas sown with particular crops created the input information for erosion modelling in GIS environment. Soil erosion risk assessment was based on (R)USLE approach. Both, the potential and the actual soil erosion risk were assessed quantificatively and qualitatively. The soil erosion risk assessment for Malopolska Voivodeship showed that only 15% of the agricultural land in the region is generally free of the risk of water erosion. For the 28.6% of agricultural land the potential medium or higher risk of erosion exist - which can result in permanent degradation of the soil profile. The study was presented in forms of digital thematic maps and reports prepared for the entire area of Malopolska Voivodeship and each administrative district as well.
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