SLIDE 1
Initial effects of burn piles on vegetation and soil following - - PowerPoint PPT Presentation
Initial effects of burn piles on vegetation and soil following - - PowerPoint PPT Presentation
Initial effects of burn piles on vegetation and soil following conifer removal from a montane meadow Sheena Hillstrom 2007-2008 SEEDS Fellow Washington State University Charles Halpern University of Washington Background Encroachment of
SLIDE 2
SLIDE 3
Background
Restoration challenges
SLIDE 4
Background
Slash disposal
SLIDE 5
Study Site
1959 1997
SLIDE 6
Study Site
SLIDE 7
Study Site
January 2006
SLIDE 8
Study Site
November 2006
SLIDE 9
Study Questions
- Do vegetation or soil characteristics vary with
distance from the center of the burn scars?
- Do burning effects extend beyond the burn
scars?
SLIDE 10
Experimental Design
U2 C E U1 Lower intensity burn (charcoal, duff) Soil cores 20x50 cm quadrat Higher intensity burn (ash)
Analysis: One-way ANOVA, post-hoc tests of means
SLIDE 11
Results
Ground-surface conditions
P o sitio n
C E U 1 U 2
Cover (%)
2 0 4 0 6 0 8 0
B a re g ro u n d
P o sitio n
C E U 1 U 2 2 0 4 0 6 0 8 0
F in e litte r
p < 0 .0 0 1
p < 0 .0 0 1 a b b b a b b b
Cover (%)
Central area: white ash Outer ring: blackened duff, charcoal
SLIDE 12
Results
Soil physical properties
Bulk Density Position C E U2 Bulk Density (g/L)
0.0 0.2 0.4 0.6 0.8 1.0
SLIDE 13
Results
Soil chemical properties
C (%)
2 4 6 8 1 0 1 2 1 4 p = 0 .3 7
T o ta l C N (%)
0 .0 0 .2 0 .4 0 .6 0 .8 p = 0 .9 1
T o ta l N P o s itio n
C E U 1 U 2
C:N ratio
5 1 0 1 5 2 0 2 5
C :N r a tio
a a b a b p = 0 .0 3 2 b
P o s itio n
C E U 1 U 2
pH
0 .0 5 .5 6 .0 6 .5 7 .0
p H
p < 0 .0 0 1 a b b b
SLIDE 14
Results
Available N
NH4+- N (mg/kg) 50 100 150 200 p < 0.001
NH4
+- N
Position
C E U1 U2 50 100 150 200 p = 0.002 a b a ab
NO
3
- - N
b
Position
C E U1 U2 NH4+- N + NO3- - N (mg/kg) 50 100 150 200
NH4
+ - N and NO 3
- - N
a b c p < 0.001 b b a c NO3- - N (mg/kg) C
E
U1 U2
Position
SLIDE 15
Results
Vegetation responses
Position
C E U1 U2
- No. species / quadrat
2 4 6 8 10 12 14
Species richness Position
C E U1 U2
Total plant cover (%)
25 50 75
p < 0.001
a a b
Total plant cover
b a b c c
p < 0.001
SLIDE 16
Results
Meadow and forest species
Meadow species cover Position
C E U1 U2
Meadow species cover (%)
10 20 30 40 50
Meadow species richness
- No. meadow species / quadrat
1 2 3 4 5 Forest species richness
- No. Forest species / quadrat
1 2 3 4 5 6
Forest species cover Position
C E U1 U2
Forest species cover (%)
10 20 30
p < 0.001 p < 0.001
a a b b a a b b a a b b a b c c
p < 0.001 p < 0.001
SLIDE 17
Conclusions
Pile burning has sever but local effects on soil and vegetation. Effects on soil N are likely to be short lived.
SLIDE 18
Conclusions
No direct effects on adjacent unburned soils or vegetation. Some survival or rapid colonization of burn edges by meadow species.
SLIDE 19
Conclusions
Little evidence of ruderal species. Minimal establishment of conifer seedlings.
SLIDE 20