by EG McPherson, A Kendall
International Journal of Life Cycle Assessment 19:1653-16652014
This study addressed the question of whether Los Angeles’ plan to plant 1 million trees would result in a net reduction in atmospheric greenhouse gases (GHG). A life-cycle GHG assessment of the project was developed based on surveys, interviews, field data, and estimates of growth and survival. More than 90,000 trees were modeled, and based on an expected survival rate of only 34%, the project was estimated to result in a net carbon source. However, when potential GHG benefits from energy conservation were included, the project became an overall carbon sink. The largest source of emissions was decomposition of mulch from dead trees. Suggestions for increasing the net benefit are provided.