Environmental impacts of extensive and intensive beef production systems in Thailand evaluated by life cycle assessment

Beef production is rapidly increasing and is accordingly becoming intensified in Southeast Asia, and the changes in beef production systems could contribute to large changes in the environmental impacts, taking into account the emission intensity of beef production. Here we assessed and compared the environmental impacts of extensive and intensive beef production systems in northeastern Thailand, using life cycle assessment (LCA). The extensive system was based on grazing and forage from grassland, and the intensive system houses cattle in the fattening phase and uses purchased concentrate feed as well as home-grown forage. An LCA model was developed based on data collected by site investigations of beef farms as well as literature and LCA databases. The processes associated with the beef-farming life cycle, i.e., animal management including biological activities of the cattle, grassland management, purchased feed production, and waste treatment were included within the LCA system boundary. The functional unit was defined as 1 kg of liveweight of marketed beef cattle. The environmental impacts of the extensive and intensive beef production systems were 14.0 and 10.6 kg CO2 equivalents for climate change, 3.5 and 11.3 MJ for energy consumption, 47.4 and 61.8 g SO2 equivalents for acidification, and 30.4 and 33.9 g PO43− equivalents for eutrophication, respectively. These impacts except for eutrophication were significantly different (P < 0.05) between the two systems. The enteric CH4 emissions were the largest sources for climate change, and the manure-related emissions were the largest sources for acidification and eutrophication. In the intensive system, the purchased feed contributed a great deal to energy consumption and to some extent to other impact categories. Our results suggested that the ongoing intensification of beef production in Thailand reduces GHG emissions while increasing impacts on energy consumption and acidification. These results provide helpful information to develop a strategy to balance the increasing productivity with the environmental sustainability of beef production in developing countries.