Investigating of Environmental Indicators of Water Footprint and Depletion ofResources in Different Scenario of Rice Cultivation

The agricultural sector is the largest consumer of water in the world and the role of this vital matter in creating or not creating environmental hazards is undeniable. In this study, environmental indicators of water footprint (potential of damage to human health, ecosystem quality, resources and depletion of water resources) and resource depletion (fossil, phosphate, potash and water resources) involved in paddy rice production were evaluated using the LCA method under three different cropping scenarios including rice-ratoon cultivation (RR), rice- secondary rice cultivation (RS) and rice- canola cultivation (RC) and two cultivation systems consisting mechanized and conventional practices. The results of environmental indicators of water use showed that the highest damage to human health, ecosystem quality and resources was obtained by Pfister et al. 0.001052 (DALY), 1630.853 (PDF * m2yr) and 10262.54 (MJ urplus), the index of fresh water degradation in the Berger et al method was 1382.122 (m3), and in Boulay et al method the damage to human health by distribution and margin of 0.176743 and 0.65772 (DALY) in the second scenario - second culture (Conventional system). Also the highest values of depletion of fossil resource value was 3.061 in second scenario- second cultivation (mechanized cultivation) and depletion of potassium and water resources were 0.04 and 0.31 in second scenario- second cultivation (conventional cultivation) and depletion of phosphate resource value was 0.6 in first and second scenario- first cultivation (conventional cultivation). Based on the results, the minimum and maximum resource depletion occurred under the RS and RR scenarios. The overall results indicated that rice cropping under the second scenario- second cultivation and in the third scenario (after canola harvesting) have destructive environmental effects from the point of view of water footprint and depletion of resources.