Research from ENST faculty and alumni finds landscape, number, and size of trees can change stormwater uptake by over 60 percent.
Street trees along a roadside in Gaithersburg, MD.
Image Credit: Tuana Phillips
A new study from UMD found that the amount of rainwater a tree absorbs varies dramatically depending on where it’s planted, and whether it is alone or with other trees. The finding is important because trees reduce rainwater runoff and improve and protect water quality. They play a key role in many urban stormwater management designs where conservation programs often give credits for planting urban trees and forests.
Understanding how different factors influence a tree’s ability to absorb rainwater is important for developing effective incentive programs and understanding the impact of these conservation efforts. The study was published in the journal Urban Forestry & Urban Greening and is a collaboration with researchers at the USFS Northern and Southern Research Stations and the non-profit Center for Watershed Protection.
Although scientists know a lot about how different tree species absorb water and the impact of varied conditions on water uptake, most of the data used for developing stormwater management plans comes from non-urban settings or arid cities like Los Angeles. Little is known about water absorption by trees in different urban settings, like in the Mid-Atlantic. This knowledge gap is especially important in the Chesapeake Bay region where five states are bound by U.S. Environmental Protection Agency laws to reduce rainwater runoff into waterways.
“We were partly surprised that there weren’t strong differences between species,” said Mitchell Pavao-Zuckerman, an associate professor in the Department of Environmental Science and Technology, and senior author of the study. “The differences really were more connected to the size of the trees, where larger trees basically had more capillary tissue to move water up through their trunks and into their canopies.”
