Increase In Water Footprint Research Articles

The water footprint of poultry, pork and beef: A comparative study in different countries and production systems

Agriculture accounts for 92% of the freshwater footprint of humanity; almost one third relates to animal products. In a recent global study, Mekonnen and Hoekstra (2012) [31] show that animal products have a large water footprint (WF) relative to crop products. We use the outcomes of that study to show general trends in the WFs of poultry, pork and beef. We observe three main factors driving the WF of meat: feed conversion efficiencies (feed amount per unit of meat obtained), feed composition and feed origin. Efficiency improves from grazing to mixed to industrial systems, because animals in industrial systems get more concentrated feed, move less, are bred to grow faster and slaughtered younger. This factor contributes to a general decrease in WFs from grazing to mixed to industrial systems. The second factor is feed composition, particularly the ratio of concentrates to roughages, which increases from grazing to mixed to industrial systems. Concentrates have larger WFs than roughages, so that this factor contributes to a WF increase, especially blue and grey WFs, from grazing and mixed to industrial systems. The third factor, the feed origin, is important because water use related to feed crop growing varies across and within regions. The overall resultant WF of meat depends on the relative importance of the three main determining factors. In general, beef has a larger total WF than pork, which in turn has a larger WF than poultry, but the average global blue and grey WFs are similar across the three meat products. When we consider grazing systems, the blue and grey water footprints of poultry and pork are greater than those for beef.

Understanding Beijing’s Water Challenge: A Decomposition Analysis of Changes in Beijing’s Water Footprint between 1997 and 2007

Beijing has been experiencing increasing water shortage alongside its astonishing economic growth over the past decades. This study conducts a quasi-dynamic input-output (IO) analysis to investigate changes in Beijing's water footprint (WF) and decompose the effects of contributing factors to the changes during 1997-2007. The analysis distinguishes "internal" and "external" WF to depict connections of Beijing's water use with outside. The results show an increase in Beijing's WF from 4342 million m(3) in 1997 to 5748 million m(3) in 2007. Almost all the increase was attributable to the expansion of the external WF, while the internal WF only changed slightly, indicating a growing dependence of Beijing on external water resources. The decomposition analysis reveals that the technological effect was the principal contributor to offset the WF increase and the structural effect stemmed from the shift of demand toward products of the tertiary industries also contributed to reducing the WF. However, these effects were not sufficient to reverse the expansion of Beijing's WF resulted from the scale effect induced by expansion of final demand and the economic system efficiency effect associated with the growth of trade between Beijing and outside. The study provides insights into Beijing's water challenge and sheds lights on the combating strategies for the future. It is also an endeavor to enhance the policy relevance of the WF studies.