“…The current reference values are based on long-term field experiments (+10 years) from more than 50 years ago (Kortleven, 1963 ;Kolenbrander, 1969). During the last decades, a common method for determining decomposition rates are incubation experiments where CO2 respiration is measured (Groenigen & Zwart, 2007;Lashermes et al, 2009;Jäger et al, 2013;Cotrufo et al, 2015;Mewes, 2017;Mondini et al, 2017). This method has been applied in several studies on decomposition of organic manures, where also HC's have been calculated (Postma & Ros, 2016 ;Groenigen & Zwart, 2007 ;Van den Burgt et al, 2011 ;VLACO, 2015 ;Reinhold et al, 2016 ;CDM, 2017, Rietra et al, in press).…”