IMPACT4SOIL OpenAire LAReferencia - Red Federada de Repositorios Institucionales de Publicaciones Científicas Latinoamericanas UnpayWall Rothamsted Repository Scientific Electronic Library Online - Chile Crossref Microsoft Academic Graph Chilean journal of agricultural research Open Access 2010-12-27 Chilean livestock production systems have intensified over the last years, with increasing amounts of N fertilizer inputs creating the potentiality for environmental damage through N pollution of water and air, so that alternative production strategies have been developed to reduce such environmental impacts. This study assesses N losses under different grazing frequencies and intensities on permanent pasture (Lolium perenne L., Festuca arundinacea Schreb., Dactylis glomerata L., and Trifolium repens L.) on an Andisol in Southern Chile. Four grazing strategies were evaluated: frequent-heavy (FH), frequent-light (FL), infrequent-heavy (IH), infrequent-light (IL), and a no grazing control (C) treatment, and each with three replicates in a randomized complete block design. Results of the experiment indicate that N leaching losses were greater in the FH treatment (58.7 kg available N ha -1 ; p < 0.05) and with most of the leaching occurring in spring (39%). On average, N ammonia (NH3) losses were 10% greater in the frequent grazing treatments in relation to the infrequent grazing treatments, since there were no significant differences (P ≤ 0.05) among individual grazing events for FH, FL and IH. Results indicate that grazing frequency affects leaching losses while grazing intensity affects ammonia emissions from the grassland. Grazing with dairy cows in Southern Chile should consider this environmental constraint to ensure sustainable production over time. lixiviación 04 agricultural and veterinary sciences amonio pastoreo 01 natural sciences ammonium leaching nitrate 0401 agriculture, forestry, and fisheries grazing NH3 volatilization volatilización de amoniaco nitrato 0105 earth and related environmental sciences Nunez, P. A., Demanet, R., Misselbrook, T. H., Alfaro, M., De La Luz Mora, M., 2010-06-01 journalpaper Chilean livestock production systems have intensified over the last years, with increasing amounts of N fertilizer inputs creating the potentiality for environmental damage through N pollution of water and air, so that alternative production strategies have been developed to reduce such environmental impacts. This study assesses N losses under different grazing frequencies and intensities on permanent pasture (Lolium perenne L., Festuca arundinacea Schreb., Dactylis glomerata L., and Trifolium repens L.) on an Andisol in Southern Chile. Four grazing strategies were evaluated: frequent-heavy (FH), frequent-light (FL), infrequent-heavy (IH), infrequent-light (IL), and a no grazing control (C) treatment, and each with three replicates in a randomized complete block design. Results of the experiment indicate that N leaching losses were greater in the FH treatment (58.7 kg available N ha -1 ; p < 0.05) and with most of the leaching occurring in spring (39%). On average, N ammonia (NH3) losses were 10% greater in the frequent grazing treatments in relation to the infrequent grazing treatments, since there were no significant differences (P ≤ 0.05) among individual grazing events for FH, FL and IH. Results indicate that grazing frequency affects leaching losses while grazing intensity affects ammonia emissions from the grassland. Grazing with dairy cows in Southern Chile should consider this environmental constraint to ensure sustainable production over time. 10.4067/s0718-58392010000200007 https://doi.org/10.4067/s0718-58392010000200007