Updated at 9:25 a.m. PST, February 18, 2010: The data from the original study regarding lawn carbon emissions versus carbon capture was found to be miscalculated. The study itself has since been amended, and this article has been corrected to reflect the new data.
While parks and lawns provide solace amidst urban and suburban sprawl, well-maintained grass is technically polluting to the environment, a study has shown.
While Nevada officials and residents have long espoused the benefits of desert landscaping in lieu of grass lawns, their focus has been on water conservation. This latest study from the University of California, Irvine, sought to determine a lawn's carbon footprint and found that it's not good.
The amount of carbon dioxide emitted from lawn-related maintenance is similar to or greater than the amount of carbon naturally collected and store by the lawn itself, the study found.
The researchers didn't simply calculate statistical averages to come to this determination. At four parks in the Irvine, Calif. area, they measured soil samples for carbon sequestration, air above the lawns for nitrous oxide emissions, and fuel consumption for park maintenance. The parks included ornamental lawns, picnic areas, and athletic fields.
The study led by Amy Townsend-Small, an Earth system science postdoctoral researcher at UC Irvine, specifically looked at the gas emissions created by lawn mowing, leaf blowing, irrigation, lawn fertilizer manufacturing, and the nitrous oxide released from soil after fertilization. Those collective lawn maintenance emissions far outweighed the amount of carbon the lawns removed from the atmosphere through photosynthesis and storage of carbon in soil.
"Lawns look great--they're nice and green and healthy, and they're photosynthesizing a lot of organic carbon. But the carbon-storing benefits of lawns are counteracted by fuel consumption," Townsend-Small said in a statement.
The UC Irvine study was funded in part by the U.S. Department of Agriculture and the Kearney Foundation of Soil Science.