Greenhouse gas balance in the conversion from extensive pasture to other agricultural systems in Andean region of Colombia

• Ano de defesa: 2015
• Autor(a) principal: Parra, Amanda Silva [UNESP]
• Tipo de documento: Tese
• Tipo de acesso: Acesso aberto
• Idioma: eng
• Instituição de defesa: Universidade Estadual Paulista (Unesp)
• Palavras-chave em Português: Sequestro de carbono; Solos; Biomassa; Aquecimento global; Pastagens; Carbon sequestration
• Link de acesso: http://hdl.handle.net/11449/126562

The challenge of agricultural sector is to reduce emissions and increase food production, taking into account environmental aspects. In Andean zone of Colombia, there is a growing need to develop GHG (greenhouse gas) mitigation techniques associated to milk production. This work focuses on the GHG emissions and potential sinks associated to milk production scenarios in the Andean zone of Colombia. The scenarios considered were: conventional agriculture of Pennisetum clandestinum in rotation with potatoes (PRP), improved pastures of Lolium multiflorum (IP) and silvopastoral system of Pennisetum clandestinum in consortium with Acacia decurrens and Trifolium repens (SPS). Based on the IPCC (2006) methodologies, the annual emission balance for a 6-year production cycle included agricultural sources and gasoline consumption related to the main agricultural phases in field, and the potential for soil C accumulation and biomass C fixation in all studied scenarios. Lower GHG emissions were estimated in PRP scenario (3,864 kg CO2eq ha-1 yr-1), but this presents the lower milk productivity. The higher GHG emissions were observed in IP scenario (7,711 kg CO2eq ha-1 yr-1), which presented the highest milk productivity and a considerable potential for soil C accumulation, that could help into the offset of its emissions. But SPS scenario, which has a milk productivity close to IP, presented the highest potential to offset GHG emission (4,878 kg CO2eq ha-1 yr-1) due to soil C accumulation plus biomass C fixation in trees