https://www.selleckchem.com/products/dtag-13.html Nitrous oxide (N2O) emissions from pasture-based livestock systems represent 34% of Brazil's agricultural greenhouse gas emissions. The forage species Brachiaria humidicola is known for its biological nitrification inhibition (BNI) capacity and N2O emissions reduction ability from urine patches under tropical conditions. However, there is little information about the effect of BNI on N2O emission and ammonia (NH3) volatilisation in the subtropics. This study aimed to (i) evaluate the potential of Brachiaria humidicola, compared with Panicum maximum (Jacq. cv. Áries; guinea grass), a broadly used grass (with no BNI capacity), to reduce N2O emissions under subtropical conditions; (ii) determine the efficacy of nitrification inhibitor dicyandiamide (DCD) to decrease N2O emissions; and (iii) determine the effect of brachiaria and DCD application on NH3 volatilisation. A field experiment was carried out using a Cambisol, where cattle urine ± DCD was applied to brachiaria and guinea grass. Over the 67-day measurement period, cumulative N2O emissions were 20% lower from urine patches in the brachiaria treatment (1138 mg N m-2, Emission factor = 1.06%) compared to guinea grass (1436 mg N m-2, Emission factor = 1.33%) (P .10). Overall, the results demonstrated that brachiaria and DCD use are strategies that can reduce N2O emissions from urine patches. Biochars are widely used to improve soil macropore structures. However, the size-dependent effects of biochars in affecting macropore structure still remain unclear. In this study, the modification of soil macropore structure following biochar addition was investigated by high-resolution X-ray tomography (CT) and advanced data analytical methods. Quantification of soil macropore structure (>52 μm) was based on the intact soil cores (5 cm in diameter and 7 cm in height) collected from biochar-amended paddy soil. The treatments were (a) control (CK), (b) rice straw biochar (RSB),