Greenhouse gas emissions from intensive livestock systems: Their estimation and technologies for reduction
Intensive agricultural systems provide opportunities for inefficiency and leakage of materials into the wider environment. Animal production systems are potential sources of two important greenhouse gases, i.e. methane and nitrous oxide. Because of the complexity of the processes involved and of the numerous interactions there is a need to consider the potential for release of these two gases on an integrated, whole farm basis to ascertain the impact of management systems. Using information from the literature, the present study examines the potential losses of CH4 and N2O from components of a model intensive dairy farm based on temperate grassland. It is estimated that a typical 76 ha dairy farm in SW England could emit nearly 12 tonnes (t) CH4-C and over 1 t N2O-N. Gaps in existing knowledge are identified and options to reduce emissions discussed.