The decline in soil organic carbon (SOC) is recognized as one of the eight (8) soil threats expressed in the European Union Thematic Strategy for Soil Protection (EC, 2006). In 2010, the European Soil Data Centre (ESDAC) collected SOC and soil erosion data in collaboration with the 38 countries of the European Environment Information and Observation Network for soil (EIONET-SOIL). The data collection followed the INSPIRE specifications for a grid of 1km x 1km grid cells and the SOC data expressed the organic carbon density (t/ha) and the SOC content (%) in the 0-30cm depth range.
Seven countries (Austria, Belgium, Denmark, Italy, Netherlands, Poland and Slovakia) submitted almost complete datasets on SOC content while a further group of six countries submitted either less than 50% of their coverage or point data which needed additional spatial interpolation. The results were compared with the modeled European SOC data of OCTOP (Jones et al, 2005). The comparison concluded that the SOC (%) in the average modeled OCTOP dataset values are almost double than the collected EIONET-SOIL data in North-East and Central Europe (Panagos et al, 2013). In Netherlands and Poland, the difference is explained due to peats which have been drained in the last 20-30 years while in Denmark, Austria and Slovakia, the pedotransfer rule (PTR) of the model OCTOP had as output much higher SOC values than the ones provided by the countries. Instead, in Northern Italy both modeled and EIONET-SOIL datasets were quite close.
Regarding the SOC Stocks, the sum the provided data for the 6 participating countries were: Bulgaria: 315 Tg, Denmark: 370 Tg, Netherlands: 299 Tg (77% coverage), Poland: 1,753 Tg (70% coverage), Italy: 994 Tg (57% coverage) and Slovakia: 122Tg (54% coverage). The SOC stocks were also compared with the amount of SOC in Europe based on OCTOP dataset (Schils et al., 2008). The results suggested that the current estimates of SOC Stock in Europe in the topsoil could be much less than the 73-79 Pg, as reported by Schils et al (2008). A more comprehensive pan-European estimation of SOC will take place after a new data collection round during 2013-2014 will be finished, with the expected contribution of more EIONET countries.