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STRI NEWS
OCTOBER 27, 2017
MONTHLY NEWSLETTER / BOLETÃN MENSUAL
TROPICAL TREE ROOTS
AND THE CARBON CYCLE
www.stri.si.edu
LAS RAÃCES TROPICALES Y EL
CICLO DEL CARBONO
sk someone to draw a tree and they will
invariably draw a trunk and branches—
leaving the roots out of the picture. In a
unique study of tropical tree roots at the Smithsonian
Tropical Research Institute published in PLOS ONE, roots
accounted for almost 30 percent of the total biomass
of young trees. The authors hope that future estimates
of carbon storage and water-use by tropical forests will
include information on root biomass and architecture.
“Studies like the article published by Baccini et al. in
the Sept. 28 issue of Science use satellite data to measure
aboveground carbon density,†said Jefferson Hall,
director of the Smithsonian’s Panama Canal Watershed
(Agua Salud) experiment. “It is fairly common practice
to calculate forest carbon storage either incorporating
root mass via a fudge-factor, or leaving it out altogether.
What percentage of a tree is underground? How does
this change with climate, soil fertility and over time?
The answers to these questions will refine our ability to
understand how forests respond to global change.â€
“During the rainy season in 2009, our team excavated
all roots down to 2 millimeters in diameter from six
species of tropical trees,†said Katherine Sinacore,
doctoral student at the University of New Hampshire.
“We chose 6- to 8-year-old trees from reforestation
experiments at Sardinilla and in Soberania National Park
in the Panama Canal Watershed, with permission from
Panama’s Ministry of the Environment.â€
“There were huge differences among species,â€
Sinacore said. “We found that trees have very different
architectures. For example, some species invest in a large
taproot that descends directly below the trunk while
other species send large roots out laterally just below
the soil surface. These trees sent smaller roo