Montane forest ecotones moved downslope in northeastern USA in spite of warming between 1984 and 2011

Jane R. Foster, Anthony W. D'Amato

Research output: Contribution to journalArticlepeer-review

61 Scopus citations


Ecotones are transition zones that form, in forests, where distinct forest types meet across a climatic gradient. In mountains, ecotones are compressed and act as potential harbingers of species shifts that accompany climate change. As the climate warms in New England, USA, high-elevation boreal forests are expected to recede upslope, with northern hardwood species moving up behind. Yet recent empirical studies present conflicting findings on this dynamic, reporting both rapid upward ecotonal shifts and concurrent increases in boreal species within the region. These discrepancies may result from the limited spatial extent of observations. We developed a method to model and map the montane forest ecotone using Landsat imagery to observe change at scales not possible for plot-based studies, covering mountain peaks over 39 000 km2. Our results show that ecotones shifted downward or stayed stable on most mountains between 1991 and 2010, but also shifted upward in some cases (13-15% slopes). On average, upper ecotone boundaries moved down -1.5 m yr-1 in the Green Mountains, VT, and -1.3 m yr-1 in the White Mountains, NH. These changes agree with remeasured forest inventory data from Hubbard Brook Experimental Forest, NH, and suggest that processes of boreal forest recovery from prior red spruce decline, or human land use and disturbance, may swamp out any signal of climate-mediated migration in this ecosystem. This approach represents a powerful framework for evaluating similar ecotonal dynamics in other mountainous regions of the globe.

Original languageEnglish (US)
Pages (from-to)4497-4507
Number of pages11
JournalGlobal change biology
Issue number12
StatePublished - Dec 2015

Bibliographical note

Publisher Copyright:
© 2015 John Wiley & Sons Ltd.


  • Climate migration
  • Decline
  • Disturbance
  • Ecotones
  • Forest dynamics
  • Global change
  • Picea rubens
  • Species range shifts


Dive into the research topics of 'Montane forest ecotones moved downslope in northeastern USA in spite of warming between 1984 and 2011'. Together they form a unique fingerprint.

Cite this