Post on 18-Mar-2016
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Effects of MPB on hydrology and post-attack vegetation dynamics
Principal investigators: Uldis Silins and Ellen Macdonald,
Ph.D. projects: Anne McIntosh and Pablo Piña
Lead field technician: Pete Presant
Annual hydrograph
Waskahegan River
0
20
40
60
80
100
120
Str
ea
mfl
ow
(m
3/s
)
1997
1998
?
Time
Re
lative
im
pa
ct
Approach
Don’t wait for MPB (issue of “control”; B.C.)
Simulate MPB attack – variable density herbicide treatment
Stand level research – processes affected by MPB
Forest water balance – how much extra water is produced ?
Short term vegetation responses – potential for compensation, recovery
Combination of
1. Before-After: Treatment:Control approach: Water balance research
2. Replicated stand level: Understory vegetation dynamics research
Treatment
Control
After Before
Main Plots = 120 x 180 m (2.2 ha) 4 treatments (below) x 2.2 ha = 8.8 ha total
Stand water balance subplot (80 x 80 m; 0.64 ha)
Vegetation subplot (80 x 60 m; 0.48 ha)
Control (undisturbed) 50% MPB kill 100% MPB kill Salvage logged (harvested) plot
- no trees left standing
* 1 tree height (20m) exterior buffer between measurement plots & adjecent stand in all plots
Additional replicated plots for vegetation work = 120 x 100 m (1.2 ha ea) 4 treatments (below) x 2 replicates = 9.6 ha total
Control (undisturbed) 50% MPB kill 100% MPB kill Salvage logged (harvested) plot
- no trees left standing
Study duration 3 yr. (1 yr pre-treatment, 2 yr. post-treatment)
Main Plots = 120 x 180 m (2.2 ha) 4 treatments (below) x 2.2 ha = 8.8 ha total
Stand water balance subplot (80 x 80 m; 0.64 ha)
Vegetation subplot (80 x 60 m; 0.48 ha)
Control (undisturbed) 50% MPB kill 100% MPB kill Salvage logged (harvested) plot
- no trees left standing
* 1 tree height (20m) exterior buffer between measurement plots & adjecent stand in all plots
Additional replicated plots for vegetation work = 120 x 100 m (1.2 ha ea) 4 treatments (below) x 2 replicates = 9.6 ha total
Control (undisturbed) 50% MPB kill 100% MPB kill Salvage logged (harvested) plot
- no trees left standing
Study duration 3 yr. (1 yr pre-treatment, 2 yr. post-treatment)
1 year pre-treatment measurements
2 years post-treatment measurements
x 2
x 1
12
stands
Jul Aug Sep Oct Nov Dec Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Jan Feb Mar
2007 2008 2009 2010
Post-Treatment Year 2
2011 2012
Analysis, write-upSurveying-layout, set up - instrumentation Pre-Treatment year Post-Treatment Year 1
• Pure pine 120 yrs.
• Medium site index
• 24-26 m height
Jul Aug Sep Oct Nov Dec Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Jan Feb Mar
2007 2008 2009 2010
Post-Treatment Year 2
2011 2012
Analysis, write-upSurveying-layout, set up - instrumentation Pre-Treatment year Post-Treatment Year 1
Jul Aug Sep Oct Nov Dec Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Jan Feb Mar
2007 2008 2009 2010
Post-Treatment Year 2
2011 2012
Analysis, write-upSurveying-layout, set up - instrumentation Pre-Treatment year Post-Treatment Year 1
Post-attack hydrologic response
1. Changes in overstory rainfall interception.
2. Changes individual tree & stand level transpiration
- Can surviving trees compensate (use more water)
3. Changes in forest floor and soil moisture storage
4. Changes in water table level, groundwater
How much extra water is produced after different levels of “red attack” ?
Gross precipitation + Evaporative demand
Overstory transpiration
Canopy interception
Rainfall interception
Rainfall event size
Inte
rce
ption (
mm
)
Rainfall interception
66 %
= 633 mm
Stemflow
Throughfall
6 m
Litter interception
Rainfall interception
Rainfall interception
Rainfall interception
43%
Individual tree & canopy transpiration
Individual tree & canopy transpiration
20%
Individual tree & canopy transpiration
On a daily basis an average tree
transpires 5.5 liters, that is about 0.7
liters per ground square meter.
During the growing season:
• ≈ 57% of precipitation is
intercepted by the canopy
• 20% of precipitation leaves as
transpiration
• Forest floor interception?
• Understory evaporation?
•Soil moisture storage?
What will happen when the MPB kills the trees?
Stand level (canopy) transpiration
0
0.5
1
1.5
2
2.5
3
3.5
4
4.5
5
1 6 11 16 21 2 7 12 17 22 3 8 13 18 23 4 9 14 19 24 5 10 15 20 1 6 11 16 21
235 236 237 238 239 240
mm
/day
50k
100k
control
Stand level (canopy) transpiration
0
0.5
1
1.5
2
2.5
3
3.5
4
4.5
5
1 6 11 16 21 2 7 12 17 22 3 8 13 18 23 4 9 14 19 24 5 10 15 20 1 6 11 16 21
235 236 237 238 239 240
mm
/day
50k
100k
control
0
0.5
1
1.5
2
2.5
3
3.5
4
4.5
5
1 6 11 16 21 2 7 12 17 22 3 8 13 18 23 4 9 14 19 24 5 10 15 20 1 6 11 16 21
220 221 222 223 224 225
mm
/day
Julian day
100 Kill
50 k
clearcut
Post-attack vegetation response
1. Changes in overstory forest structure.
2. Changes in understory plant community composition (shrubs, seedlings, vascular plants, bryophytes).
3. Recruitment of downed woody debris (DWD).
4. Changes in below-ground processes (nutrient availability, microbial community, decomposition).
What is the early trajectory of post-attack response (advanced growth, understory
vegetation) after different levels of “red attack” ?
23
Objective 1: Overstory
Characterize the overstory forest structure (0.02 ha plots)
• Species
• Live status
• Dbh
• Height
• Crown Vigor
• Cover (hemispherical photos)
24
Pre-treatment - Overstory Basal Area vs Block
Block
HTL NRH PSH
Ba
sa
l a
rea (
m2
/ha
)
0
10
20
30
40
50
60
Live
Dead
Basal Area
25
Pre-treatment - Overstory TPH vs Block
Block
HTL NRH PSH
Tre
es p
er
Hecta
re
0
500
1000
1500
2000
2500
3000
Live
Dead
Trees Per Ha
26
Pre-treatment - Overstory
Mean dbh vs block
Block
HTL NRH PSH
Me
an
db
h (
cm
)
0
5
10
15
20
25
All
live
dead
Mean DBH
27
Objective 2: Understory
Quantify differences in the understory
plant community composition
Seedlings/Saplings (pine)
Vascular plants (shrubs, forbs, graminoids)
Non-vascular plants (bryophytes, lichens)
Abundance (% cover) and richness by
species
Mean Cover by Block (+/- SE)
Block
HTL NRH PSH
Me
an
co
ve
r o
f q
ua
dra
t
0
20
40
60
80
100
120
140
160
Pre-treatment - Understory
28
Cover
Mean Richness by Block (+/- SE)
Block
HTL NRH PSH
Me
an
sp
ecie
s r
ich
ne
ss o
f q
ua
dra
t
0
2
4
6
8
10
12
14
Pre-treatment - Understory
29
Quadrat Richness
Pre-treatment - Understory
Block
HTL NRH PSH
Sp
ecie
s R
ich
ne
ss
0
20
40
60
80
100
Quadrats
Species census
Total Richness
31
Objective 3:
Downed Woody Debris
Quantify DWD
Transects: biomass
estimates
(Megagrams/ha)
32
Mean Fuel (+/- SE) by Block
Block
HTL NRH PSHDead w
oody d
ebris (
Megagra
ms/h
a)
0
10
20
30
40
50
60
Pre-treatment – Downed Woody Debris
Fuel Biomass
33
Objective 4: Below-Ground
Quantify differences in below-ground attributes
Decomposition (cellulose paper in mesh bags)
Microbial biochemical activity & biomass
Community-level physiological profiles (CLPP)
Phospholipid fatty acid (PLFA) analysis
Nutrient availability (PRS probes)
Soil moisture (TDR)
Stay Tuned!
The Future?
Support for the work
Foothills Research Institute
FRIAA / AB SRD
West Fraser Timber Co. Ltd.
Milo Mihajlovich
…Thank you for listening
Coming years …
Jul Aug Sep Oct Nov Dec Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Jan Feb Mar
2007 2008 2009 2010
Post-Treatment Year 2
2011 2012
Analysis, write-upSurveying-layout, set up - instrumentation Pre-Treatment year Post-Treatment Year 1