Historical change and functional control of montane forest distribution in northern New England.

Recipient Organization
UNIVERSITY OF VERMONT
(N/A)
BURLINGTON,VT 05405

Performing Department
PLANT BIOLOGY

Non Technical Summary
The distribution of forests in New England may change in response to global warming. We will examine how the current distribution of New England forests has been affected by recent climate change and we will predict how these forests will change in response to predicted future climate change.

Animal Health Component

20%

Research Effort Categories

Basic

80%

Applied

20%

Developmental

(N/A)

Classification

Knowledge Area (KA)	Subject of Investigation (SOI)	Field of Science (FOS)	Percent
123	0610	1070	40%
123	0613	1070	20%
123	0620	1070	40%

Knowledge Area
123 - Management and Sustainability of Forest Resources;

Subject Of Investigation
0610 - Conifer forests of the North; 0620 - Broadleaf forests of the North; 0613 - Mixed conifer-broadleaf forests;

Field Of Science
1070 - Ecology;

Keywords

Goals / Objectives
We will investigate the effects of climate change and acid deposition on montane forests in northern New England. The relative importance and potential for interactions between climate change and anthropogenic acidification on the dynamics of forests is largely unknown.

Project Methods
We will examine whether recent declines in populations of high elevation forests are primarily controlled by i) climate, ii) acid deposition, or iii) their interaction. We will distinguish between these mechanisms by examining current and historic forest dynamics in plots stratified along elevational transects located on four montane sites that encompass a broad range of susceptibility to acid deposition. At each site, we will place plots across an elevational range that encompasses northern hardwood forests and high elevation conifer forests. We will (1) quantify historical shifts of major forest types through resurveys of historic forest plots, comparison of historic and current aerial photographs and satellite images. We will (2) attribute shifts to proximate climatic and acid-deposition factors and their interactions. Lastly, we will (3) forecast changes in forest distribution in response to projected climate change using a biogeographic model based on biophysical variables.

Progress 10/01/07 to 10/01/10

Outputs
OUTPUTS: We investigated the impact of regional warming on montane forests in Vermont. We compared the present and past tree composition of vegetation plots that were originally established in the early 1960's in order to assess changes in forests associated with regional warming trends. We also used historical aerial photographs and satellite images to determine elevational shifts in forest trees associated with regional warming trends. We used a simulation model to project the future distribution of forests in New England in response to projected climate change. We have disseminated results of our work their publication in scientific journals as well as through mainstream media outlets. PARTICIPANTS: One Ph.D. student was partially supported by this project. One postdoctoral associate was involved in this project. One computer programmer was involved in this project. TARGET AUDIENCES: We have presented results of our research at professional scientific meetings. PROJECT MODIFICATIONS: Nothing significant to report during this reporting period.

Impacts
We detected a significant shift in forest composition and a rapid upslope shift in the ecotone between lower elevation hardwood forests and upper elevation boreal forests over the last half century. Northern hardwood trees have increased in abundance in the ecotone while boreal forests have declined. The change in forest composition and upward shift in the econtone is consistent with regional warming trends. We have projected continuing shifts of forests to higher elevations with a general expansion of more southernly forest species and reductions in area of boreal forest.

Publications

Beckage B., B. Osborne, C. Pucko, D.G. Gavin, T. Siccama, and T. Perkins. 2008. An upward shift of a forest ecotone during 40 years of warming in the Green Mountains of Vermont, USA. Proceedings of the National Academy of Sciences 105(11): 4197- 4202.
Gavin, D.G., B. Beckage, and B. Osborne. 2008. Forest dynamics and the growth decline of red spruce and sugar maple on Bolton Mountain, Vermont: a comparison of modeling methods. Canadian Journal of Forest Research 38(10): 2635-2649.
Tang, G., and B. Beckage. 2010. Projecting the distribution of forests in New England in response to climate change. Diversity and Distributions 16: 144-158.
Pucko, C., B. Beckage, T. Perkins, and W. Keeton. Species shifts in response to climate change: Individual or shared responses 2011. In review.

Progress 10/01/07 to 09/30/08

Outputs
OUTPUTS: We are investigating the impact of regional warming on montane forests in Vermont. We are comparing the present and past tree composition of vegetation plots that were originally established in the early 1960's in order to assess changes in forests associated with regional warming trends. We are using historical aerial photographs and satellite images to determine elevational shifts in forest trees associated with regional warming trends. We are examining potential interactive effects of anthropogenic acid deposition (acid rain) and regional warming on forest dynamics. We have detected a significant shift in forest composition and a rapid upslope shift in the ecotone between lower elevation hardwood forests and upper elevation boreal forests over the last half century. The upward shift in the econtone is consistent with regional warming trends. PARTICIPANTS: One graduate student is currently being partially supported by this project. TARGET AUDIENCES: Nothing significant to report during this reporting period. PROJECT MODIFICATIONS: Nothing significant to report during this reporting period.

Impacts
The regional climate of Vermont has warmed by 1.5 degrees C over the last several decades and these trends are expected to continue in response to human emissions of greenhouse gases. Understanding the changing nature of Vermont forests will allow for planning that can mitigate against the negative consequences of global warming on the economy Vermont (e.g., maple syrup production, tourism associated with leaf watching).

Publications

Beckage B., B. Osborne, C. Pucko, D.G. Gavin, T. Siccama, and T. Perkins. 2008. An upward shift of a forest ecotone during 40 years of warming in the Green Mountains of Vermont, USA. Proceedings of the National Academy of Sciences 105(11): 4197-4202.
Gavin, D.G., B. Beckage, and B. Osborne. 2008. Forest dynamics and the growth decline of red spruce and sugar maple on Bolton Mountain, Vermont: a comparison of modeling methods. Canadian Journal of Forest Research 38(10): 2635-2649.