Silvopastoral systems with Tithonia diversifolia (Hemsl.) A. Gray reduce N2O–N and CH4 emissions from cattle manure deposited on grasslands in the Amazon piedmont

Cattle manure deposited in pastures is an important source of nitrous oxide (N2O–N) and methane (CH4) emissions. Environmental conditions and soil characteristics affect emissions of these two gases, and therefore, it is important to conduct studies in local conditions to generate emission factors to improve greenhouse gas (GHG) estimates, as well as to identify mitigation strategies. N2O–N and CH4 fluxes from soil, feces and urine were determined for two cattle production systems during two seasons, and emission factors (EFs) were calculated. The static closed chambers technique was used in three conventional systems (CSs) and three silvopastoral systems (SPSs) with Tithonia diversifolia in the Colombian Amazon piedmont. SPSs presented lower emission factors than CSs for N2O–N from urine patches in both seasons (2.64 vs.1.49% and 1.69 vs. 0.89% of nitrogen (N) deposited for the transition and rainy season, respectively) (p = 0.004), N2O–N from feces in the rainy season (0.17 vs. 0.13% of N deposited for CSs and SPSs) (p = 0.046), and CH4 in the transition rainy season (1.08 vs. 0.83 g of CH4/kg of dry matter of feces for CSs and SPSs, respectively) (p = 0.005); with the EFs determined, the cumulative emissions for each system were estimated in 176.8 and 145.3 kg of CO2 equivalent per hectare per year in the CSs and SPSs. We concluded that SPSs can emit lower amounts of CH4 and N2O–N from manure and provide an alternative for mitigation of these gases generated by bovine manure under tropical humid conditions.