Impacto de Alnus acuminata Kunth en los flujos de N2O y calidad del pasto Pennisetum clandestinum Hochst. ex Chiov.

The Aliso Alnus acuminata Kunth is a forest species of the of the Colombian Andes associated with Kikuyu grass as silvopastoral system (SPS) and fixe atmospheric N. The SPS was compared with 0, 50, 100, 150 and 200 kg N ha-1 year-1 at 30, 45 and 60 days on pasture quality, expressed as green forage (GF), dry matter (DM), percentage of crude protein (% CP) and N absorbed, also fluxes N2O emissions to the atmosphere were evaluated. The SPS exceeded to 0 and 50 kg.N.ha-1 in all variables, less in the N2O emission fluxes that was greater than 0 kg.N.ha-1 (P<0.05), equal to 50 kg.N.ha-1 (P>0.05), and in GF was similar to 100 kg.N.ha-1 (p>0.05). 150 and 200 kg.N.ha-1.year-1 exceeded all the variables to the SSP. A higher GF and DM was achieved at 45 days and %CP at 30 days.El Aliso Alnus acuminata Kunth es un forestal del trópico alto de Colombia que se asocia con pasto Pennisetum clandestinum Hochst. ex Chiov. como sistema silvopastoril (SSP) y fija N atmosférico. El SSP se comparó con 0, 50, 100, 150 y 200 kg.N.ha-1.año-1 a los 30, 45 y 60 días sobre la calidad del pasto, expresada en forraje verde (FV), materia seca (MS), porcentaje de proteína cruda (%PC) y N absorbido; también se evaluaron los flujos de emisiones de N2O a la atmósfera. El SSP superó a 0 y 50 kg.N.ha-1 en todas las variables, menos en los flujos de emisiones de N2O que fue mayor a 0 kg.N.ha-1 (P<0.05) e igual a 50 kg.N.ha-1 (P>0.05) y en FV fue similar a 100 kg.N.ha-1 (p>0.05); 150 y 200 kg.N.ha-1.año-1 superó en todas las variables al SSP. Se alcanzó mayor FV y MS a los 45 días y %PC a los 30 días

Alnus acuminata Kunth impact on N2O fluxes and quality of Pennisetum clandestinum grass Hochst. ex Chiov. grass

The Aliso Alnus acuminata Kunth is a forest species of the of the Colombian Andes associated with Kikuyu grass as silvopastoral system (SPS) and fixe atmospheric N. The SPS was compared with 0, 50, 100, 150 and 200 kg N ha-1 year-1 at 30, 45 and 60 days on pasture quality, expressed as green forage (GF), dry matter (DM), percentage of crude protein (% CP) and N absorbed, also fluxes N2O emissions to the atmosphere were evaluated. The SPS exceeded to 0 and 50 kg.N.ha-1 in all variables, less in the N2O emission fluxes that was greater than 0 kg.N.ha-1 (P0.05), and in GF was similar to 100 kg.N.ha-1 (p>0.05). 150 and 200 kg.N.ha-1.year-1 exceeded all the variables to the SSP. A higher GF and DM was achieved at 45 days and %CP at 30 days