In a recently published article, JRC scientists present a new harmonised, high-resolution (500 m), soil erodibility map of 25 EU Member States (for which data were available). They found that the incorporation of stoniness as a factor of soil composition significantly affected estimates of soil erodibility.
While soil erosion is the most widespread form of soil degradation worldwide, it is difficult to measure at large scales. The greatest obstacle to soil erosion modelling at larger spatial scales is the lack of data on soil characteristics. The K-factor, the generally accepted measure of soil erodibility, is related to soil properties such as organic matter content, soil texture, soil structure and permeability.
In developing the new high resolution soil erodibility maps, the authors used the first pan-European soil dataset, Land Use/Cover Area frame Study (LUCAS, 2009) and a Cubist regression model to estimate the mean K-factor for Europe. For the first time, they included soil structure and stoniness in the K-factor estimation, which allowed for better estimations of soil permeability and protection against erosion, respectively. The K-factor dataset was verified against national, regional and local studies found in the literature. The incorporation of the protective effect of surface stone cover resulted in an average 15% decrease of the K-factor. This is particularly significant in calculating the soil erodibility of Mediterranean countries, which have the highest amounts of surface stone cover.
The proposed model provides a framework for the digital mapping of soil erodibility at the continental scale with greater spatial accuracy, and allows for the establishment of rules upon which the K-factor can be estimated from remotely sensed data. As soil erodibility can be influenced by agricultural practices, the K-factor dataset can guide the implementation of conservation practices. The K-factor dataset can also be used to classify high-risk areas as being ecologically vulnerable, thereby helping to guide local conservation actions.
The high-resolution datasets of the K-factor and the Kst-factor (which incorporates stoniness) are available to download from the European Soil Data Centre (ESDAC).