Abstract:

The objective of this study was to evaluate the differences in the greenhouse gas emissions and energy use of fertilizers applied between the production of certified organic pear, green food certified pear, and conventional pear in two areas in China. Data were collected from interviews with farmers during 2007 and 2008. Three calculation methods for energy value of manure had been found in the literature: substitution method, by-product method, and thermal method. The choice of various calculation methods for estimating the energy value of manure turned out to have great influence on the results in terms of energy use of fertilizers applied in different pear production systems. The greenhouse gas emissions were lowest from fertilizers applied in certified organic pear production, whereas the environment burden was highest in certified organic pear production system. Possible explanations for these differences were discussed.