Environmental indicators of dairy systems in Central Santa Fe: results from the OLE and CREA simulation models

JAUREGUI, JOSE M; CANDIOTI, FRANCISCO; BERHONGARAY, GONZALO

Congreso; 44º Congreso Argentino de Producción Animal; 2021

Beef and dairy cows are usually held responsible for a significant amount of greenhouse gas (GHG) emissions. In fact, about 10% of global GHG emissions are derived from livestock production (Gerber et al., 2013). Of those GHGs, enteric methane (CH4) represents the largest source released from livestock. Reducing methane emissions is needed to achieve more sustainable systems and to meet global CO2 reduction demands. In general, high input dairy farms (i.e. confined systems) are associated with lower emissions per kg of product. However, such farms usually sow a larger proportion of annual crops, have higher grazing efficiency and occupy a small area of their farm with pastures, which can have a negative impact on soil carbon balance. Grazing systems, on the other hand, generally have larger areas occupied with perennial pastures. Nevertheless, since grazing dairy cows produce less milk per head, emissions per kg of product are usually higher. The question that remains is whether soil carbon (C) balance from crops and pastures is different in either system. Another important environmental issue raised by livestock production is the amount of water used per kg of product (and per kg of protein), as many parts of the world suffer from water scarcity. The objective of this work was to use the OLE simulator to analyse three contrasting dairy farms in terms of their environmental indicators (i.e. enteric CH4 emissions and litres of water used per litre of milk and per kg of protein) and to contrast CH4 emissions (in CO2 equivalents; methane x 28) with their soil C inputs using OLE and CREA models, respectively.