Answers to common questions in Ecological Footprint accounting

Abstract

1. IntroductionThe Ecological Footprint measures the amount of biolog-ically productive land and water area required to supportthe demands of a population or productive activity. Sinceits creation more than 15 years ago by William Reesand Mathis Wackernagel (Wackernagel, 1991a,b; Rees,1992; Wackernagel and Rees, 1996), Ecological Footprintaccounts have been created for nations (Wackernagel andRees, 1996; Bicknell et al., 1998; Van Vuuren and Smeets,2000; Ferng, 2001; Haberl et al., 2001; Lenzen and Mur-ray, 2001; McDonald and Patterson, 2004; von Stokar etal., 2006; WWF, 2006; Moran et al., 2008), cities andregions (Folke et al., 1997; Wackernagel, 1998; Best FootForward, 2002; Bagliani et al., 2003; EPA Victoria, 2005;Walsh et al., 2006; Lammers et al., 2008), businesses (Bar-rett and Scott, 2001; Lenzen et al., 2003), and individuals(Redefining Progress, 2002; EPA Victoria, 2008). Acrossscales, analysts apply Ecological Footprint accountingmethods to understand a population’s or activity’s demandfor the planet’s limited capacity to provide a range ofecosystem goods and services.The basic methodologies behind Ecological Footprintaccounting have been widely published in various forms(Wackernagel et al., 1996; Ferng, 2001; Lenzen et al.,2001; Monfreda et al., 2004; WWF, 2006; Galli et al.,2007; Kitzes et al., 2007, 2008), and these publications