Fig.1From: Validating the regional estimates of changes in soil organic carbon by using the data from paired-sites: the case study of Mediterranean arable landsStudy area and main soil systems from the Italian soil information system http://www.soilmaps.it/. The samples collected only in 1994 (black dots) and both in 1994 and 2017 (red triangles) were projected on the mapBack to article page