Lettuce to reduce greenhouse gases: A comparative life cycle assessment of conventional and community agriculture

Abstract

One of the most frequently touted benefits of community gardens and the local food movement is the potential to reduce greenhouse gas emissions through local low input production. Commercially grown foods, grown as monocultures on large acreage typically require large inputs of fertilizers, water and pesticides along with long transport distances and refrigerated storage to reach consumers. What impact can we have when labor, water, and nutrients are supplied locally? To evaluate this, we used life cycle assessment to compare the greenhouse gas emissions of supplying lettuce to customers in Seattle with either conventionally grown lettuce from central California or with lettuce grown in a community garden (Figs. 1 and 2).