[MCN] Which US forests most at risk from drought?

[Lance Olsen]

Global Change Biology  August 2016

US forest response to projected climate-related stress: a tolerance perspective
Jean Liénard, John Harrison,Nikolay Strigul
Washington State University Vancouver, Vancouver, WA, USA
-------------------------------------------------------------------------
"Vulnerable areas include mostly the Midwest 
United States and Northeast United States, as 
well as high-elevation areas of the Rocky 
Mountains. We also infer stress incurred by 
shifting climate should create an opening for the 
establishment of forest types not currently seen 
in the conterminous United States."
--------------------------------------------   

Abstract
http://onlinelibrary.wiley.com/doi/10.1111/gcb.13291/full

Although it is widely recognized that climate 
change will require a major spatial 
reorganization of forests, our ability to predict 
exactly how and where forest characteristics and 
distributions will change has been rather 
limited. Current efforts to predict future 
distribution of forested ecosystems as a function 
of climate include species distribution models 
(for fine-scale predictions) and potential 
vegetation climate envelope models (for 
coarse-grained, large-scale predictions). Here, 
we develop and apply an intermediate approach 
wherein we use stand-level tolerances of 
environmental stressors to understand forest 
distributions and vulnerabilities to anticipated 
climate change. In contrast to other existing 
models, this approach can be applied at a 
continental scale while maintaining a direct link 
to ecologically relevant, climate-related 
stressors. We first demonstrate that shade, 
drought, and waterlogging tolerances of forest 
stands are strongly correlated with climate and 
edaphic conditions in the conterminous United 
States. This discovery allows the development of 
a tolerance distribution model (TDM), a novel 
quantitative tool to assess landscape level 
impacts of climate change. We then focus on 
evaluating the implications of the drought TDM. 
Using an ensemble of 17 climate change models to 
drive this TDM, we estimate that 18% of US 
ecosystems are vulnerable to drought-related 
stress over the coming century. Vulnerable areas 
include mostly the Midwest United States and 
Northeast United States, as well as 
high-elevation areas of the Rocky Mountains. We 
also infer stress incurred by shifting climate 
should create an opening for the establishment of 
forest types not currently seen in the 
conterminous United States.
-- 
------------------------------------------------------------------------
"Full of recent references and statistics, 
Harvesting the Biosphere adds to the growing 
chorus of warnings about the current trajectory 
of human activity on a finite planet, of which 
climate change is only one dimension. One can 
quibble with some assumptions or tweak Smil's 
calculations, but the bottom line will not 
change, only the time it may take humanity to 
reach a crisis point."

Stephen Running. "Approaching the Limits" Science 15 March 2013.

Book review. Harvesting the Biosphere: What we 
have taken from Nature. by Vaclav Smil .  MIT 
Press, Cambridge, MA, 2012. 315 pp. $29, £19.95. 
ISBN 9780262018562.




-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://bigskynet.org/pipermail/missoula-community-news_bigskynet.org/attachments/20160726/a01de99d/attachment-0002.html>