Author(s): PALHARES, J. C. P.; CHARLON, V.; HERRERO, M. A.; SALAZAR, F.

Summary: The aims of this study were to assess the grey water footprint in South America dairy systems and analyzed the impact of effluent characteristics and environmental legislation on water footprint value. Grey water footprint quantifies freshwater pollution by the amount of water needed to re-dilute polluted freshwater back to an accepted national threshold value. Water footprints were determined collecting primary data in 61 farms of Argentina (Buenos Aires and Santa Fe provinces) and 20 dairies in Chile. The study considerate total phosphorus in the effluent and the production system as a no-point source of pollution. Phosphorus effluent concentration varied from 0.005 kg m3 to 0.686 kg m3 between farms. Chile had the highest phosphorus concentrations and Buenos Aires region the lowest, which could be related mainly to effluent management practices. Grey water footprint varied from 0.59 L of water kg-1 to 1.77 L of water kg-1 of milk. The maximum value of grey water footprint was observed with dairy slurry with the highest value to phosphorus concentration. Grey water footprint of dairy production will be less per unit of milk as milk production increases. It was observed in the results. The concentration of the element in the effluent, the element used to calculate grey water and the environmental law has a significant impact on footprint values.

Publication year: 2017

Types of publication: Paper in annals and proceedings

Unit: Embrapa Southeastern Livestock

Keywords: Effluent, No-point, phosphorus