Quantifying the environmental impacts of alfalfa production in different farming systems

Abstract

In this study a cradle to farm gate life cycle assessment (LCA) of alfalfa production in different farming systems was investigated to examine alfalfa production systems from environmental perspective. Data were randomly collected from 75 alfalfa production farms from Iranian West Azerbaijan province. Functional unit was considered as one ton of baled alfalfa hay. The results revealed that electricity had the most share on environmental emissions. Annual quantities of CO2, N2O and NH3 emissions in alfalfa production were calculated as 51.27, 0.0807 and 0.7312 kg t−1, respectively. By application of CML-IA baseline V3.02/World 2000 methodology, LCA results revealed that total quantities of abiotic depletion, global warming, ozone layer depletion, human toxicity, fresh water aquatic ecotoxicity, marine aquatic ecotoxicity, terrestrial ecotoxicity, photochemical oxidation, photochemical oxidation, acidification, and eutrophication were found to be 109E-5 kg Sbeq, 988 kg CO2eq, 802E-7 kg CFC-11eq, 150 kg 1,4-DBeq, 22.5 kg 1,4-DBeq, 173E3 kg 1,4-DBeq, 4.19 kg 1,4-DBeq, 284E-3 kg C2H4eq, 6.64 kg SO2eq, and 1.38 kg PO43−eq, respectively. Classification results of farms into small, medium and large farms clearly demonstrated that small farms produce more environmental loads. Employing modern and efficient irrigation procedures in all alfalfa cultivation systems and use of new electrical pumps with higher efficiency for supplying water from agricultural water wells and also integration of small farms for a better management of inputs are recommend for decreasing the harmful environmental impacts.