In fact, the landfilling process was found the main contributor to the Climate Change damage category due to emissions of CH4, CO2 and to a lesser extent N2O (859.06 kg CO2eq/t waste) which are the three main Greenhouse Gases (GHGs). It is well documented that the GHGs are the main causes of global warming by absorbing infrared radiations in the atmosphere, trapping heat and warming the surface of the Earth [63]. Given the proportion of CH4 and by comparing the environmental impact of the three GHGs released during landfilling, Hong et al. [30] labeled CH4 as the main contributor to the adverse eco-effects of ‘landfilling’ scenario. These gases are also released at drastically lower amounts during the composting process (16.80 kg CO2eq/t waste). Overall, composting process in the scenarios Sc-3 (and to a lesser extent in the Sc-1) had an adverse effect on the Climate Change damage category. This was not true for the scenarios Sc-0 and Sc-4 in which composting materials were obtained from the AD. In fact, the composting process through anaerobic digestion (AD-compost) had two major advantages over the aerobically-produced compost. The first and more important advantage was the lower environmental burden associated with the composting process through the AD. The second advantage was associated with compost final quality. In better words, the AD-compost (which can be obtained by the scenarios Sc-0 and Sc-4) contained higher amounts of humus which in turn resulted in better compost quality compared to the aerobically-produced compost (which can be obtained by the scenarios Sc-3 and Sc-1). In general, Iran׳s soil is poor in organic matters (humus