Eastern forest composition has been altered due to a change in disturbance regimes, not due to climatic changes, a study carried out by Penn State University suggests.
Forests in the Eastern United States remain in a state of “disequilibrium” after the clear-cutting and large-scale burning that occurred in the late 1800s and early 1900s, says Marc Abrams, professor of forest ecology and physiology.
The state of Minnesota is experiencing a significant overhaul of its forest populations, where trees such as the American basswood, black cherry, red maple, sugar maple, and white oak are becoming increasingly prevalent, whereas the region’s more characteristic species such as the white spruce and balsam fir tree struggle to get used to increasing temperature and wet winter storms, the Nature World News recently reported.
Marc Abrams, a researcher from Penn State’s College of Agricultural Sciences is disputing that climate is a primary factor involved in forests overhaul, especially in the eastern United States forests. He further insisted that these forests are still struggling from the burning and clear-cutting of large-scale forests.
Moreover, Abrams noted, since about 1930 aggressive forest-fire suppression has had a far greater impact on shifts in dominant tree species than small differences in temperatures.
“Looking at the historical development of Eastern forests, the results of the change in types of disturbances — both natural and man-caused — are much more significant than any change in climate,” said Abrams, who is the Steimer Professor of Agriculture in the Department of Ecosystem Science and Management.
“Over the last 50 years, most environmental science has focused on the impact of climate change. In some systems, however, climate change impacts have not been as profound as in others. This includes the forest composition of the eastern U.S.”
Abrams compared pre-settlement – original land survey data along with present vegetation conditions in the Eastern United States, in a recent study published in the journal Global Change Biology. It revealed that the “change” experience by the eastern forests is similar to the still ongoing turbulent results of European disturbances on what was once thought to be a balanced forest system.
Abrams noted that this doesn’t mean that the climate isn’t having its own influences. “Land-use change often trumped the impacts of a warming climate, and this needs greater recognition in climate change discussions, scenarios and model interpretations,” Abrams added.
Eastern Forest Composition Altered Due to Change in Disturbance Regimes