mpbep 2012 04 prsnttn ecologicalimpactsofmpbonfoothillsofalberta
DESCRIPTION
http://foothillsri.ca/sites/default/files/null/MPBEP_2012_04_Prsnttn_EcologicalImpactsOfMPBOnFoothillsOfAlberta.pdfTRANSCRIPT
René Alfaro, Brad Hawkes, Lara vanAkker
and Bill Riel Pacific Forestry Centre, Victoria, BC, Canada
Jodi Axelson Dept Geography, University of Victoria
Ian Cameron Azura Informetrics
Ecological impacts of the Mountain Pine
Beetle on the Foothills of Alberta
2
Contents
Introduction
Disturbances: drivers of ecosystem change
Need for establishing baselines
Need for forecasting growth and yield and
flow of ecosystem services following MPB
Work in the BC and Alberta
Forest transformation by MPB actual and
stand simulations
Knowledge gaps and opportunities
Conclusions
3
Ecology of lodgepole pine:
a fire regenerated species
4
Life after fire
5
The mountain pine beetle Forest management, climate change
Fire suppression and
selective harvesting for
species other than pine
during previous century,
created large forests of
pine
Beetle survival has
improved over much of
western Canada during
recent decades due to
global warming, allowing
populations to invade
areas formerly unsuitable
for MPB
6
Probable range of the MPB
A very plastic insect= High
potential for invasion
US Distribution from
McCambridge and Trostle 1970
Canada Distribution: from Alberta
and BC sources
7
Largest pine beetle outbreaks in BC and Alberta in recent history
Aerial surveys
begin
History of beetle outbreaks in BC
1980 1985 2011
BC Montana Border 31 years later
Ecological and timber impacts
9
The Cariboo-Chilcotin Plateau plots Established 1987, remeasured in 2001 and 2008
3 biogeoclimatic zones
Mixed-severity fire regime
Stands dominated by Pl
10
East Slopes sites
New range
Historic range
20 Years after MPB in Waterton National Park
12
Waterton Lakes NP, Red Rock Canyon
– 1982 and 2008
13
Methodology: Establishing beetle disturbance
baselines
Dating coarse woody debris
Dating regen. cohorts
Dating canopy layers
1. Past distribution of MPB outbreaks and return interval
2. Understanding impacts. Timber and ecosystem
Disturbance history in “even” and uneven aged stands
15
Results: Stand development after beetle
MPB is a natural thinning agent
Promotes increased growth among
the surviving trees
Allows for the establishment of
seedlings in understory
Creates coarse woody debris
History of the canopy layers of an “even-aged” lp stand Logan Lake, Kamloops
Axelson J., Alfaro, R., and Hawkes, B. 2009.
17
Beetle and stand dynamics: Bull Mtn. Study
Heath and Alfaro 1990 (re-surveyed in 2001)
Overstory Understory
Tree ring widths (mm)
1882-2001
Chilcotin: Growth release after 1970-80’s outbreak
19
Beetle
history of
in BC and Alberta
1630 1640 1790 1800 1810 1820 1830 1840 1850 1860 1870 1880 1890 1900 1910 1920 1930 1940 1950 1960 1970 1980 1990 2000
1630 1640 1790 1800 1810 1820 1830 1840 1850 1860 1870 1880 1890 1900 1910 1920 1930 1940 1950 1960 1970 1980 1990 2000
Sta
nd
MAN1MAN4MAN5WAT
MAN3MAN2OK14CASTMOY
OK15OK16
BLR10ST2BPARS
BLR11ST2CANG1ANG2
KATHCBAN08BLR09
K302KET2
KATHAKATHB
KET3KET1WHIT
CAN12CAN13
LAL3LAL2LAL1
CORRTUNKSAVOHALL
KOOTREV02CRAN
REV01BAN05CC163CC359CC103
GOLD03GOLD04
CC101CC102CC105CC106CC104CC120CC122CC121CC128CC125SASKXCC129CC130CC119CC116CC118CC107CC117CC124CC126
BULLCC108CC109CC115CC114CC110CC111CC113CC123CC112
JASPJWGDOIG
TWD2TWD3TWD9TWD6TWD7TWD8TWD5TWD4
PG
MAN1MAN4MAN5WATMAN3MAN2OK14CASTMOYOK15OK16BLR10ST2BPARSBLR11ST2CANG1ANG2KATHCBAN08BLR09K302KET2KATHAKATHBKET3KET1WHITCAN12CAN13LAL3LAL2LAL1CORRTUNKSAVOHALLKOOTREV02CRANREV01BAN05CC163CC359CC103GOLD03GOLD04CC101CC102CC105CC106CC104CC120CC122CC121CC128CC125SASKXCC129CC130CC119CC116CC118CC107CC117CC124CC126BULLCC108CC109CC115CC114CC110CC111CC113CC123CC112JASPJWGDOIGTWD2TWD3TWD9TWD6TWD7TWD8TWD5TWD4PG
1890’s 1930’s 1970’s
20
Bull Mountain 2001: A 320 year old tree: outbreaks every 52 years (40 years for entire BC)
Lodgepole pine growth
Year
Mea
n ra
dial
gro
wth
(mm
)
0.0
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
1.8
2.0
2.2
2.4
2.6
2.8
3.0
1683
1700
1720
1740
1760
1780
1800
1820
1840
1860
1880
1900
1920
1940
1960
1980
2000
1970's1930's1860's1800's1760's
Douglas-fir
21
Beetle creates advance regeneration
22
From simple post-fire
stand structure…
Beetle and stand dynamics
To multiple cohort structure
23
Beetle creates coarse woody debris CWD from the 1970’s-80’s outbreak
24
CWD from the 1930’s
outbreak
Beetle creates coarse woody debris
25
Fire interactions Chilcotin
0
1
2
3
4
5
6
7
8
1564
1579
1594
1609
1624
1639
1654
1669
1684
1699
1714
1729
1744
1759
1774
1789
1804
1819
1834
1849
1864
1879
1894
1909
1924
1939
1954
1969
1984
1999
Year of scarring
Num
ber
of d
etec
ted
fire
scar
s (N
= 2
2)
1869 1906
1842
1776
Fire control
implemented
26
Brad plays with fire
27
Resiliency of the Chilcotin Forest after two
outbreaks
Density (stems/ha) Volume (m3/ha)
Layer Mean SE Mean SE
Overstory
(>7.0cm DBH) 413 84 27.9 5.3
Understory (<7.0cm DBH, taller than 1.5m)
1035 168
Regeneration (shorter than 1.5m) 4709 1429
Total 6157
Live pine in 2008 after 1970’s and 2000’s outbreak
Resiliency of the Chilcotin Forest after two
outbreaks
29
AC3R3T125
Initial conditions 2008
3 cohorts
30
AC3R3T150
2033
31
AC3R3T158PRE
2041 (immediately prior to light outbreak)
32
AC3R3T158
2041 Light outbreak removes 30 % BA
33
AC3R3T175
2058 New cohort is born
34
AC3R3T191PRE
2074 (immediately prior to outbreak)
35
AC3R3T191
2074 Massive outbreak kills 70% BA
36
AC3R3T200
2083
37
AC3R3T225
2108 New cohort is born
38
Results: Waterton National Park
Pine is mostly down
Forest dominated by
shade tolerant
39
History of beetle at Waterton
Stand 1
Stand 2
Stand 3
Stand 4
Stand 5
1880 1885 1890 1895 1900 1905 1910 1915 1920 1925 1930 1935 1940 1945 1950 1955 1960 1965 1970 1975 1980 1985 1990 1995 2000 2005 2010
Outbreaks
1970’6-1980’s 1920’-1930’s
40
Overstorey Saplings Regeneration
41
Results: Waterton
Marked decline in lodgepole pine density
Increase in non-host species such as spruce and fir from 1981
to 2010
With the exception of stand 1, sapling and seedling densities
have increased in all stands from 2002 to 2010
High degree of variability in stocking between stands
Composition made up almost entirely of shade tolerant species
42
Conclusion: Stand dynamics cycle in BC
43
Conclusion: Stand dynamics cycle in Alberta
44
Conclusions
Stand-replacing fires initiate even-aged lp stands
Reduced fire in 20th century: MPB directs stand
dynamics
MPB transform stands into multiple age cohort
forests, initiated by repeated beetle thinning.
Or transition to other stand types
Long term impacts: alleviated by the presence of a
sub-canopy, and advance regeneration layers
which will form reasonably well stocked forests in
the future.
45
Impacts on timber and ecosystem services
Timber production is heavily impacted
Ecological impacts or ecosystem services:
If disturbance is part of cycle, business as usual
In novel habitats: transition to different
ecosystems
Caveat: climate change will alter natural
disturbance regimes.
46
“I’ll be back”
Dendroctonus ponderosanegger
http://cascadiascorecard.typepad.com/
48
Questions?
Mpbep 2010 03 prsnttn effectsofsimulatedmpbonhydrologyandpostattackvegetationandbelowgrounddynamicss
Hlp 2009 12 prsnttn infosessionpreliminaryevidenceofmixedseverityfireregimesineastslopesofrockymount