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<div>"Drought and heat-induced tree mortality is accelerating in
many forest biomes as a consequence of a warming climate, resulting in
a threat to global forests unlike any in recorded history (1-12).
Forests store the majority of terrestrial carbon, thus their loss may
have significant and sustained impacts on the global carbon cycle
(11,12).<b> We use a hydraulic corollary to Darcy's law, a core
principle of vascular plant physiology (13)</b>, to predict
characteristics of plants that will survive and die during drought
under warmer future climates.<b> Plants that are tall with isohydric
stomatal regulation, low hydraulic conductance, and high leaf area are
most likely to die from future drought stress</b>. Thus, tall trees of
old-growth forests are at the greatest risk of loss, which has ominous
implications for terrestrial carbon storage. This application of
Darcy's law<b> indicates today's forests generally should be
replaced by shorter and more xeric plants</b>, owing to future warmer
droughts and associated wildfires and pest attacks. The Darcy's
corollary also provides a simple, robust framework for informing
forest management interventions needed to promote the survival of
current forests.<b> Given the robustness of Darcy's law for
predictions of vascular plant function,</b> we conclude with high
certainty that today's forests are going to be subject to continued
increases in mortality rates that will result in substantial
reorganization of their structure and carbon storage."</div>
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<div><b>Bold emphasis added</b></div>
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<div>Nathan G. McDowell and Craig Allen. Darcy's law predicts
widespread forest mortality under climate warming.<i> Nature Climate
Change</i> Published Online: 18 MAY 2015</div>
<div>DOI: 10.1038/NCLIMATE2641</div>
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<div><font face="Geneva" size="-1" color="#000000">"</font><font
face="Geneva" size="-1" color="#121F35">Although it is encouraging to
know that Douglas-fir forests will acclimate to a warmer climate, in
some regions, this increased drought tolerance may come at the expense
of a relatively fast growth rate that is prized by land managers. 'We
found that populations could have good growth and reasonable drought
resistance, or reasonable growth and good drought resistance. You
can't have both maximum growth<i> and</i> maximum drought resistance,'
Bansal explains<i>."</i></font><br>
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<div><font face="Cambria" size="-2"
color="#FFFF00"><u>http://www.fs.fed.us/pnw/sciencef/scifi179.pdf</u></font
><br>
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<div><font face="Cambria" size="-2"
color="#000000">==================================-<br>
</font><font face="Cambria" color="#000000">"</font><font
face="Times New Roman" color="#000000">I KEEP six honest
serving-men<br>
(They taught me all I knew);<br>
Their names are What and Why and When<br>
And How and Where and Who."<br>
<br>
Rudyard Kipling<br>
<br>
Briefly discussed here:<br>
</font><font face="Cambria"
color="#FFFF00"><u
>http://schoolofthinking.org/2008/08/kiplings-six-honest-men/<br>
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color="#000000"></font></div>
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