MILWAUKEE, March 28 (UPI) -- Kudzu, a plant scourge of the U.S. Southeast, is on the move north with a warming climate but its tropical cousins are of more concern, researchers say.
Dubbed by some the "stranglers of the tropics," the woody vines, or lianas, are choking trees and changing forest ecosystems throughout the tropics, a National Science Foundation release reported Monday.
Ecologist Stefan Schnitzer of the University of Wisconsin-Milwaukee said data from sites in eight studies show lianas are overgrowing trees in every instance.
"Any alteration of tropical forests has important ramifications for species diversity, productivity -- and ultimately the global carbon cycle," Schnitzer said.
Lianas, found in most tropical lowland forests, are "non-self-supporting structural parasites that use the architecture of trees to ascend to the forest canopy," he said.
Intense competition from lianas for above- and below-ground resources limits tropical tree growth and survival.
Lianas usually have a high canopy-to-stem ratio, Schnitzer said, "which allows them to deploy a large canopy of leaves above those of the host tree, competing aggressively with their hosts for sunlight, water and nutrients."
Robert Sanford, program director in the National Science Foundation's Division of Environmental Biology, which funded the research, said increasing liana abundance may have far-reaching consequences for tree species in tropical forests.
