Influence of Mountain Pine Beetle and Fire Disturbances on Stand Dynamics of Alberta’s Lodgepole Pine Forests Brad Hawkes, RenÊ Alfaro, and Jodi Axelson Pacific Forestry Centre, Victoria, BC, Canada
Contents Waterton Lakes National Park long-term plots FRI MPB program funded stand dynamics study of Foothills Summary of dendro evidence of past MPB outbreaks in AB Rockies Growth and Yield impacts after MPB Recce of WLNP and Southern Rockies PSP’s 2
Ecology of lodgepole pine: a fire regenerated species – my fire ecology research until ‌.
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Past 9 Years – Mountain Pine Beetle and Fire Disturbance influences on forest ecosystems of lodgepole pine
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
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Establishing disturbance baselines: past distribution and return interval
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Repeated Sampling to Determine Stand Dynamics after MPB Chilcotin Plateau 1987 2001 2008
Kootenay NP 1993 2003
Waterton Lakes NP 1983 2003 2009?
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MPB in Waterton Lakes National Park 20 Years After Mountain Pine Beetle 1983-2003
1983
2003
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Importance of seedbed to lodgepole pine regeneration
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ROAD SIDE
Understory stand structure in Waterton Lakes National Park
seedlings No lodgepole pine found in 25 plots No lodgepole pine found in 25 plots
Mostly Serotinous and Closed Cones
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Aspen
Poplar Spruce
Subalpine fir Douglas-fir
Lodgepole pine
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Prognosis G&Y model runs with Fire and Fuel Extension Live Tree Density
Snag Density 6
1000
5 1000 stem/ha
stem/ha
800
600
400
4 3 2
200
1
0
0
1980
1990
2000
2010
2020
2030
1980
1990
2000
2010
2020
2030
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Stand dynamics cycle
Waterton
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Location of sampled PSPs in the Lower Foothills and the Upper Foothills
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Stand History – Lower Foothills Biotic scars (Root collar weevil?)
Birth of the overstory
Canopy disturbances
Birth and death of CWD
Regeneration
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Stand dynamics cycle
N. Alberta 17
Examining spatial variability of lodgepole pine across the eastern Foothills Used chronologies developed in Lower and Upper Foothills in 2008 (15) Used chronologies developed from 20022005 in southern Alberta with historical MPB outbreaks (11) Computed Factor Analysis (FA) to see dominant modes of variability and patterns of tree-growth in 26 lodgepole pine 18 chronologies
FC1
FC2 FC4
FC3
Large growth release in early 1920s characteristic of MPB releases in BC
Large growth reduction from mid-1940s to mid-1970s – strong correlation to the PDO
Growth releases in the 1940s and 1980s attributable to MPB outbreak in Waterton and Crowsnest area
Growth pattern declining over entire record – senescence? competition? 20
3
2
Standardized Index
1
0
-1
-2 March PDO FC2 -3 1900
1910
1920
1930
1940
1950
1960
1970
1980
1990
2000
FC2 and March Pacific Decadal Oscillation Index (PDO). The PDO 21 is a major mode of variability in the north Pacific which affects climate across North America, particularly in western Canada.
1630 1640 1790 1800 1810 1820 1830 1840 1850 1860 1870 1880 1890 1900 1910 1920 1930 1940 1950 1960 1970 1980 1990 2000
Stand
Beetle history of in BC and Alberta
PG TWD4 TWD5 TWD8 TWD7 TWD6 TWD9 TWD3 TWD2 DOIG JWG JASP CC112 CC123 CC113 CC111 CC110 CC114 CC115 CC109 CC108 BULL CC126 CC124 CC117 CC107 CC118 CC116 CC119 CC130 CC129 SASKX CC125 CC128 CC121 CC122 CC120 CC104 CC106 CC105 CC102 CC101 GOLD04 GOLD03 CC103 CC359 CC163 BAN05 REV01 CRAN REV02 KOOT HALL SAVO TUNK CORR LAL1 LAL2 LAL3 CAN13 CAN12 WHIT KET1 KET3 KATHB KATHA KET2 K302 BLR09 BAN08 KATHC ANG2 ANG1 ST2C BLR11 PARS ST2B BLR10 OK16 OK15 MOY CAST OK14 MAN2 MAN3 WAT MAN5 MAN4 MAN1
1890’s
1930’s
1970’s
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PG TWD4 TWD5 TWD8 TWD7 TWD6 TWD9 TWD3 TWD2 DOIG JWG JASP CC112 CC123 CC113 CC111 CC110 CC114 CC115 CC109 CC108 BULL CC126 CC124 CC117 CC107 CC118 CC116 CC119 CC130 CC129 SASKX CC125 CC128 CC121 CC122 CC120 CC104 CC106 CC105 CC102 CC101 GOLD04 GOLD03 CC103 CC359 CC163 BAN05 REV01 CRAN REV02 KOOT HALL SAVO TUNK CORR LAL1 LAL2 LAL3 CAN13 CAN12 WHIT KET1 KET3 KATHB KATHA KET2 K302 BLR09 BAN08 KATHC ANG2 ANG1 ST2C BLR11 PARS ST2B BLR10 OK16 OK15 MOY CAST OK14 MAN2 MAN3 WAT MAN5 MAN4 MAN1
1630 1640 1790 1800 1810 1820 1830 1840 1850 1860 1870 1880 1890 1900 1910 1920 1930 1940 1950 1960 1970 1980 1990 2000
Stand dynamics cycle
N. Alberta
Waterton
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Future of forests: modeling using TASS In-depth stand reconstructions (timing of disturbances, overstory and understory initiation) and current stand information (tree density, DBH, height) inform growth and yield models. We collaborate with BC Ministry of Forests and Range, and Ian Cameron to compute growth and yield of MPB stands using the Tree Age and Stand Simulator (TASS) Simulate stands with MPB disturbances and forecast future growth and yield 24
3 cohorts
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Initial conditions 2008
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2033
27
2041 (immediately prior to light outbreak)
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2041 Light outbreak removes 30 % BA
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2058 New cohort is born
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2074 (immediately prior to outbreak)
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2074 Massive outbreak kills 70% BA
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2083
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2108 New cohort is born
2009 Recce of Waterton Lakes NP and PSPs Examine potential of doing more detailed stand dynamics research on Waterton plots and PSPs impacted by 80s outbreak. Eg determine when saplings were established in plots. Qualify sapling and canopy tree release and growth after 80s outbreak thinned stands. Predict future growth and yield with scenarios of potential future impacts of MPB. 34
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