Semi-natural vegetation in agricultural land: European map and links to ecosystem service supply

Semi-natural vegetation in agricultural land mainly includes extensively managed grasslands, agro-forestry areas and all vegetated features that are not used for crop production, such as hedgerows, buffer strips, field margins and woodlots. Semi-natural vegetation plays a major role in the supply of ecosystem services such as pollination, pest control, water quality control and erosion prevention. The efficiency of ecosystem services for agriculture should therefore depend upon the spatial distribution of semi-natural vegetation. In spite of such a relevance, semi-natural vegetation in agricultural land has never been mapped at the European scale. Therefore, we report here the first 1- km resolution map of semi-natural vegetation in agricultural land at the European Union scale. For that, we use an innovative convergence-of-evidence mapping method. We also present an assessment and a classification of the relation between semi-natural vegetation and ecosystem service supply at the regional scale. The major improvements in our mapping method are the following: (1) both large and small patches of perennial vegetation are detected in fine-resolution satellite images by incorporating the spectral rule-based preliminary classifier, (2) the identification of semi-natural grassland is enhanced, (3) European ancillary maps are used to help mapping of woody vegetation and identification of agro-ecosystems. Validation shows that our output map is 34.3 % more accurate than pre-existing components. In addition, results show that regulating ecosystem services increase with the abundance of semi-natural vegetation in agricultural lands with a coefficient R (2) of 0.67. The results also show no specific trend in relation to provisioning ecosystem services. These findings mean that semi-natural vegetation is usually beneficial for regulating services, whereas the relation to provisioning services is strictly context-dependent. Overall our study supports greening measures design in the frame of the Common Agricultural Policy for 2014-2020. Results also will help to identify green infrastructure elements and priority areas for ecological restoration.