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western C</title></head><body>
<div><font face="Geneva">Global Change Biology October 2015</font><br>
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<div><font face="Geneva"><b>Net aboveground biomass declines of four
major forest types with forest ageing and climate change in western
Canada's boreal forests</b></font><font face="Arial"><br>
</font><font face="Geneva">Han Y. H. Chen, Yong Luo</font><font
face="Arial"><br>
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face="Geneva"
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face="Arial"><br>
</font><font face="Geneva">"Our results suggest that persistent
warming and decreasing water availability have profound negative
effects on forest biomass in the boreal forests of western
Canada."</font><font face="Arial"><br>
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face="Geneva"
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</font><font face="Geneva">Abstract</font><font face="Arial"><br>
</font><font
face="Geneva"><u
>http://onlinelibrary.wiley.com/doi/10.1111/gcb.12994/full</u></font><br
>
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<div><font face="Geneva">Biomass change of the world's forests is
critical to the global carbon cycle. Despite storing nearly half of
global forest carbon, the boreal biome of diverse forest types and
ages is a poorly understood component of the carbon cycle. Using data
from 871 permanent plots in the western boreal forest of Canada, we
examined net annual aboveground biomass change (?AGB) of four major
forest types between 1958 and 2011. We found that ?AGB was higher for
deciduous broadleaf (DEC) (1.44 Mg ha?1 year?1, 95%
Bayesian confidence interval (CI), 1.22-1.68) and early-successional
coniferous forests (ESC) (1.42, CI, 1.30-1.56) than mixed forests
(MIX) (0.80, CI, 0.50-1.11) and late-successional coniferous (LSC)
forests (0.62, CI, 0.39-0.88). ?AGB declined with forest age as well
as calendar year. After accounting for the effects of forest age, ?AGB
declined by 0.035, 0.021, 0.032 and
0.069 Mg ha?1 year?1 per calendar year in DEC, ESC, MIX
and LSC forests, respectively. The ?AGB declines resulted from
increased tree mortality and reduced growth in all forest types except
DEC, in which a large biomass loss from mortality was accompanied with
a small increase in growth. With every degree of annual temperature
increase, ?AGB decreased by 1.00, 0.20, 0.55 and 1.07
Mg ha?1 year?1 in DEC, ESC, MIX and LSC forests,
respectively. With every cm decrease of annual climatic moisture
availability, ?AGB decreased 0.030, 0.045 and
0.17 Mg ha?1 year?1 in ESC, MIX and LSC forests, but
changed little in DEC forests. Our results suggest that persistent
warming and decreasing water availability have profound negative
effects on forest biomass in the boreal forests of western Canada.
Furthermore, our results indicate that forest responses to climate
change are strongly dependent on forest composition with
late-successional coniferous forests being most vulnerable to climate
changes in terms of aboveground biomass.</font><font face="Arial"
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<div><font face="Cambria" size="-1"
color="#000000"><b
>====================================================================<span
></span>===============<br>
</b></font><font face="Bookman Old Style" size="-1"
color="#000000">"The growth in CO2 emissions closely follows the
growth in Gross Domestic Product (GDP) corrected for improvements in
energy efficiency."<br>
<br>
P. Friedlingstein, et al. "Update on CO2 emissions."</font></div>
<div><font face="Bookman Old Style" size="-1"
color="#000000"><i>Nature Geoscience.</i> Published online: 21
November 2010</font></div>
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color="#000000"
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<div><font face="Geneva" size="-1" color="#000000">"An impressive
study across all of northern Russia from 1953-2002 showed a shift in
tree allometries. In areas where summer temperatures and precipitation
have both increased, a general increase in biomass (up 9%) is
primarily a result of increased greenery (33% more carbon in leaves
and needles), rather than woody parts (roots and stem). In areas that
have experienced warming and drying trends, greenery has decreased,
and both roots and stems have increased (Lapenis et al.
2005)."</font></div>
<div><font face="Geneva" size="-1" color="#000000"><br></font></div>
<div><font face="Geneva" size="-1" color="#000000">" ...
there is little theoretical or experimental support to suggest that
climate warming will cause absolute climatic tolerances of a species
to evolve sufficiently to allow it to conserve its geographic
distribution."</font></div>
<div><font face="Bookman Old Style" color="#000000"><br></font></div>
<div><font face="Bookman Old Style" color="#000000">Camille Parmesan.
"Ecological and Evolutionary Responses to Recent Climate
Change."<i> Annual Review of Ecol. Evol. & Systematics </i>
2006. 37:637-69</font><font face="Geneva" size="-1"
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