Forest disturbance in mountain environments:
Hydrologic impacts of increasing landscape heterogeneity
Sarah Boon & Katie Burles
University of Lethbridge
Mountain Hydrology Research Group

Outline
• Geography
• Mountain snow
• Forests, climate & disturb ance
• Stand scale results
• Watershed scale approaches
• Interesting considerations
Crowsnest Pass, AB

Research locations
1. Vanderhoof; Fraser Lake
3. Mayson Lake;
Upper Penticton Ck
2. Crowsnest Pass

Controls on mountain snow
• Topography
• Climate
• Vegetation
• Accumulation
– elevation, slope, wind, interception
• Ablation
– elevation, aspect, temperature/radiation, transmissivity

Climate change and feedbacks
• SWE, snowmelt timing/magnitude
(Westerling et al. 2003)
• Forest disturbance
– wildfire
– insect infestation
The ‘red hand of death’, Fraser Exp.
Forest, CO
Glenrosa-Westbank wildfire, BC, July 2009

Forest disturbance and snow
Vanderhoof, BC Crowsnest Pass, AB

Snow accumulation: post-pine beetle
2007
High snow year
2008
Low snow year
Alive Dead
(Boon 2007; 2008; in review)

Snow accumulation: post-wildfire
• Sublimation
• Redistribution
40
35
30
25
20
15
10
5
Burned Healthy (Reference)
0
16-Feb-09 8-Mar-09 28-Mar-09 17-Apr-09 7-May-09 27-May-09
Burn
Healthy
(Burles, unpub. data)

Snowmelt energetics: post-beetle
HEALTHY INFESTED

Snowmelt energetics: post-beetle
Modelled melt 2007
Modelled melt components
(Boon 2008; 2009)

Snowmelt energetics: post-wildfire
HEALTHY BURNED

Snowmelt energetics: post-wildfire
BURN
HEALTHY
2.5
2.0
1.5
1.0
0.5
0.0
-0.5
-1.0
2.5
2.0
1.5
1.0
0.5
0.0
-0.5
-1.0
LHF
SHF GHF K*
L*
Q m
LHF GHF
SHF K* L* Q m
Components of the snowmelt energy balance (Apr 1 …
(Burles, unpub. data)

Snowmelt energetics: post-beetle litter
0.4
0.3
0.2
0.1
0.0
0
1.0
0.9
0.8
0.7
0.6
0.5
10 20 30 40 50 o = young pine x = mature mixed species
∆ = clearcut
60 bare ground
80 90 100 70
Young pine Mature mixed Clearcut
(Winkler et al., 2010)

Mosaic of forest stand types
Kelowna, BC
Harney Peak, SD
Kootenay National Park, BC

Work to date: pine beetle
• Binary forest cover
– dead, harvested OR healthy
– no combinations
– no regenerating stands
• Limited process approach
– peak flow focus
Vancouver
Percent change in peak flow between 1995 baseline and 2007 MPB infestation levels
(Carver et al. 2010)

Work to date: wildfire
• Rain-dominated catchments
– what about snow?
• Limited modelling work
– Europe, Australia
– many process studies
Moody & Martin 2001

Research underway
• Snowmelt and runoff
– response to wildfire, pine beetle
– incorporate patchwork effects
• Cold Regions hydrologi cal model (Pomeroy et al. 2007)
• Validate with field datasets
– 20 y paired watershed experi ment
Upper
Penticton
Creek
(UPCk)

Interesting considerations
• Hydrologic connectivity
– soil moisture vs. forest structure
• Scale
– key processes in stand vs. watershed
• Topographic gradient
– are low elevations hydrologically insensitive to forest change?

Fall 2010 AGU session
Snowmelt partitioning in mountain environments (Boon, Tromp-van Meerveld,
Allen)
• Overland flow, soil moisture, subsurface flow, and deep groundwater recharge
• Field experiments, numerical modelling studies, theoretical approaches

Acknowledgements
Future Forest Ecosystems Scientific Council of BC
Forest Management Branch
Canadian Forest Service
Mountain Pine Beetle Initiative
Mountain Hydrology Research Group
Katie Burles
Dave Dixon
Reed Davis
Dave Lewis
Dez Tessler
Josh Padolsky
Angus Duncan
Ryan MacDonald

Outline
• Background
• Research areas
– snow accumulation
– snowmelt energetics
– snow hydrology
• New directions
• Summary
Crowsnest Pass, AB

Snow accumulation: watershed-scale
• Topography, vegetation controls
– field data, interpolation, statistical approaches
• New instrumentation applications
– total station
• Effects of disturbance
(Dixon, unpub. data)

Watershed scale impacts
• Accumulation patterns
• Melt onset
• Hydrologic connectivity
• Runoff generation

Climate change: Temp & PPT
Change from 1980-1999 to 2080-2099
(IPCC 2007)

Climate change effects
Trends in 1 Apr SWE 1978-2000
(Rodenhuis et al. 2009)
Trend in PNW freshet timing
(Cayan et al. 2001)

Climate change feedbacks: MPB
MPB-killed area w/ time
The ‘red hand of death’, Fraser Exp. Forest, CO
Kill area & PDO relationship
(Macias Fauria & Johnson 2009)

Climate change feedbacks: wildfire
Wildfire frequency and temperature
Glenrosa-Westbank wildfire, July 2009
Snowmelt timing & wildfire
(Westerling et al. 2003)