Human activities play a key role in total greenhouse-gas emissions,of which the global food system is responsible for up to onethird of all (Gilbert, 2012). In this chain, cropping systems account for 14% of global net CO2 emissions (Cooper et al., 2011; Mohammadi et al., 2013). The environmental awareness of both consumers and producers has sharply increased over the past decade; since consumers seek cleaner production, producers of this sector try to meet their demands.