CARBON SEQUESTRATION IN WATER-STABLE AGGREGATES UNDER BIOCHAR AND BIOCHAR WITH NITROGEN FERTILIZATION

Daniel Bajčan, Jan Horak, Peter Kovačik, Vladimir Šimansky

Abstract: An experiment of different application rates of biochar and biochar combined with nitrogen fertilizer was conducted at the newly established experimental field (spring 2014) on Haplic Luvisol located in Nitra region of Slovakia during the growing season of spring barley. The aims of this study were to evaluate the effects of biochar and biochar combined with nitrogen fertilization (1) on the soil organic carbon (SOC) and labile carbon (CL) contents in water-stable macro- (WSAma) and microaggregates (WSAmi), and (2) on carbon sequestration in water-stable macro- (CSCma) and micro-aggregates (CSCmi). The treatments ( 3replicates) consisted of 0, 10 and 20 tha-1 of biochar application (B0, B10 and B20) combined with 0, 40 and 80 kg N ha-1 of nitrogen fertilizer applied (N0, N40, N80). There was observed signifi cant increase of SOC in WSAma (by 11%) in
B20N0 compared to B0N0. The biochar in both rates 10 and 20 t ha-1 together with 40 and 80 kg N ha-1 did not have effects on SOC in WSA. Significant increase of CL in WSAma and CL in WSAmi were found only in B20N80 compared with B0N0. Overall, the highest values of CSCma were in the following order B10N80 > B20N0 > B0N0 > B20N40 > B10N0 > B20N80 > B10N40. Overall, the highest average values of CSCmi were found in treatments with 10 t ha-1 of biochar combined with 80
kg N ha-1.

Keywords: aggregates; biochar; labile carbon; soil organic carbon

Date published: 2017-07-07