Post on 24-Jul-2020
Impacts of the Drought
and Heat in 2003 on ForestsScientific Conference 17 – 19 November 2004
Freiburg, Germany
Working Group 5: Forest Growth
Impacts of Drought and Heat on Tree and Forest Growth
A Synthesis of Studies on Short-, Medium- and Long-term Effects Observed under Temperate Climatic
Conditions
Hans-Peter Kahle, Institute for Forest Growth, University Freiburg
Questions addressed:
Was Tree Growth Affected by the Heat and Drought in 2003?
- To which Extent? (% of “normal”)
- Most affected Species (on the same site): Beech vs. Spruce
- Most affected Sites: Elevation and Aspect
- Most affected Stands: dense vs. open
- Most affected Crown Class: dominant vs. intermediate.
Drought 2003Working Group 5: Forest Growth
Scaling issues addressed:
Short-term effects on growth? Effects in 2003? (% of “normal”)
Medium-term consequences?Effects during the next 5 years?
Long-term consequences?Effects beyond the next 5 years?
Drought 2003Working Group 5: Forest Growth
Weather Conditions in 2003at two meteo stations in Baden-Württemberg:
- Karlsruhe (DWD): 112 m asl
- Schauinsland (UBA): 1205 m asl
Drought 2003Working Group 5: Forest Growth
high elevation
(Data source: DWD 2004, UBA 2004)
Weather Conditions in 2003: Air Temperature
low elevation
Weather Conditions in 2003: Air Temperature Anomalies
(Data source: DWD 2004, UBA 2004)
rKA/SC = 0.9135
Weather Conditions in 2003: Precipitation
(Data source: DWD 2004, UBA 2004)
low elevation
high elevation
(Data source: DWD 2004, UBA 2004)
Weather Conditions in 2003: Precipitation Anomalies
rKA/SC = 0.7607
Mean air temperature 1994-2002 and 2003
02468
10121416182022
11,4 18,1 6,0 11,7
Jan-Dec May-Sep Jan-Dec May-Sep
Karlsruhe Schauinsland
Tp (°
C)
(Data source: DWD 2004, UBA 2004)
(112 m) (1205 m)
Mean air temperature 1994-2002 and 2003
02468
10121416182022
11,4 11,9 18,1 20,3 6,0 7,2 11,7 14,8
Jan-Dec May-Sep Jan-Dec May-Sep
Karlsruhe Schauinsland
Tp (°
C)
+ 0,5°C + 2,2°C + 1,2°C + 3,1°C
+ 4,4 % + 12,2 % + 20,2 % + 27,0 %
(Data source: DWD 2004, UBA 2004)
(112 m) (1205 m)
Precipitation sum 1994-2002 and 2003
0
500
1000
1500
2000
2500
813 352 2142 894
Jan-Dec May-Sep Jan-Dec May-Sep
Karlsruhe Schauinsland
Pr (m
m)
(Data source: DWD 2004, UBA 2004)
Precipitation sum 1994-2002 and 2003
0
500
1000
1500
2000
2500
813 561 352 245 2142 1488 894 532
Jan-Dec May-Sep Jan-Dec May-Sep
Karlsruhe Schauinsland
Pr (m
m)
- 252 mm- 107 mm
- 654 mm
- 362 mm
- 31 %
- 31 %
- 31 %
- 40 %
(Data source: DWD 2004, UBA 2004)
240 mm
211 mm
376 mm
344 mm
(Data source: DWD 2004)
21.5 °C23.8 °C
16.4 °C 17.8 °C
11.6 °C 12.3 °C
23.0 °C25.5 °C
17.9 °C 19.4 °C
13.0 °C 13.9 °C
Climate Trends at Karlsruhe: Temperature & Precipitation
(Data source: DWD 2004)
Climate Trends at Karlsruhe: Climatic Water Balance
- 71 mm
-135 mm
111 mm
50 mm
-127 mm
-208 mm
(Station Karlsruhe, Data source: DWD 2004)
Weather in Selected Warm and Dry Years in 1895-2004
Temperate oceanic forestTemperate continental forestBoreal coniferous forestTemperate mountain systemSubtropical dry forestSubtropical mountain systemTemperate steppeBoreal mountain system
Weather Conditions in Selected Years in Europe (Ecozones according to FAO classification)
(Map source: FAO 2002)
Subtropica
l dry
forest
Subtropica
l mountai
n system
Temperate oce
anic
forest
Temperate co
ntinental
fore
st
Temperate steppe
Temperate m
ountain sys
tem
Boreal
conife
rous fo
rest
Boreal
mountain sys
temPolar
-70
-60
-50
-40
-30
-20
-10
0
Prec
ipita
tion
(Mai
-Sep
)(d
evia
tion
in %
of 1
975-
2002
)
194719762003
(Data source: New et al. 1999, 2000, 2002)
Subtropica
l dry
fore
st
Subtropica
l mountai
n syste
m
Tempera
te oce
anic
fore
st
Tempera
te co
ntinental
fore
st
Tempera
te ste
ppe
Tempera
te m
ountain sys
tem
Boreal
conife
rous fo
rest
Boreal
mountai
n syste
m
Polar
0,0
1,0
2,0
3,0
4,0
5,0
6,0
7,0
Tem
pera
ture
(May
-Sep
) (d
evia
tion
in K
of 1
975-
2002
)
194719762003
(Data source: New et al. 1999, 2000, 2002)
Radial Growth by Species and Elevation
- Dendrometer studies
Drought 2003Working Group 5: Forest Growth
Point Dendrometer Mounted on a Beech Stem (Hauser 1999)
Stainless steel body with displacement transducer
Sensor head
5 cm
Black Forest Vosges Mountains Rhine Valley
Dendrometer Measurements - Field Sites
Günterstal: 450 m aslHeibrain: 750 m asl
Schauinsland: 1250 m asl
Dietenbach: 220 m asl
Beech Low Elevation (220 m asl) Oak
Spruce Low Elevation (450 m asl) Beech
22.05.xx
06.05.03
08.04.xx
01.04.03 06.10.xx
23.06.xx
02.06.03
02.08.0303.04.03
08.04.xx
26.06.03
29.09.xx
27.10.03
Spruce Medium Elevation (750 m asl) Beech
Spruce High Elevation (1250 m asl) Beech
020406080
100120140160180200
450 750 1250
FASY FASY FASY
GUE HEI SCHnu
mbe
r of g
row
ing
days
1999-20022003
Number of GrowingDays derivedfromDendrometerData
Beech
020406080
100120140160180200
450 750 1250
PCAB PCAB PCAB
GUE HEI SCH
num
ber o
f gro
win
g da
ys
1999-20022003
Spruce
Occurrence of may shoot of Norway spruce at Schauinsland (1250 m asl)
120130140150160170
1992
1993
1994
1995
1996
1997
1998
1999
2000
2001
2002
2003
2004
2005
year
day
of y
ear
(Data source: Henhappl 2004)
Radial growth in 2003
0
20
40
60
80
100
120
140
0 500 1000 1500
Altitude (m asl)
ir 20
03 (I
ndex
200
2=10
0)
BeechOakSpruceLinear (Spruce)Linear (Beech)
Radial growth in 2004
0
20
40
60
80
100
120
140
0 500 1000 1500
Altitude (m asl)
ir 20
04 (I
ndex
200
2=10
0)
BeechOakSpruceLinear (Spruce)Linear (Beech)
Rate of radial displacement of European Beech(expressed in % of the maximum rate during the period 1999-2002)
220 m asl
450 m asl
750 m asl
1250 m asl
Radial Growth and Aspect of the Site
Drought 2003Working Group 5: Forest Growth
Radial Growth of European Beech at Möhringen (750 m asl)
Aspect: north-east south-west
Radial Growth of European Beech at Möhringen (750 m asl)
Radial Growth of European Beech at Möhringen (750 m asl)
• level of growth larger on north-east facing slope!• growth reduction smaller on south-west facing slope!• recovery faster on south-west facing slope!
Radial Growth and Stand Density
Drought 2003Working Group 5: Forest Growth
Radial growth of European Beech at Möhringen (760 m asl)
control basal area 15 m² basal area 10 m²
Radial Growth of European Beech at Möhringen (760 m asl)
control BA 15 m² BA 10 m²
Rate of radial displacement of Beech at Möhringen(expressed in % of the maximum rate during the period 2001-2002)
Radial Growth of European Beech at Möhringen (760 m asl)
• the lower the stand density the higher the level of growth!• no clear difference in growth reduction in 2003!• no clear difference in recovery in 2004!
Radial Growth and Crown Class
Drought 2003Working Group 5: Forest Growth
Radial Growth of European Beech at Möhringen (760 m asl)
dominant codominant intermediate
• the higher the crown class the higher the level of growth!• intermediate trees show larger growth reduction in 2003!• no clear differences between crown classes in recovery
in 2004!
Radial Growth of European Beech at Möhringen (760 m asl)
Restrospective Growth AnalysesTwo sites in the Black Forest:
- Municipal forest of Freiburg (Dist. I/Abt. 23, 650 m asl)
- Community Forest Elzach (Elztal, 400 m asl)
Drought 2003Working Group 5: Forest Growth
Annual Radial Increment, Black Forest, 650 m asl. (I/23)
Norwayspruce (PCAB)
Silver fir(ABAL)
Douglas fir (PSME)
European beech (FASY)
2003
Standardized Annual Radial Increment, Black Forest, 650 m asl. (I/23)
2003
Annual Radial Increment of Beech in Relation to Spruce(Black Forest I/23, 650 m asl.)
Annual Radial Increment of Dead and Alive Norway Spruce
Annual Radial Increment of Dead vs. Alive Norway Spruce
Detail: stem cross section Norway spruce (Elztal, Tree no. 6, Radius 2)
2002 2001 2000 1999 1998 19972003
2004 1996
grey value profile
Annual Radial Increment of Dead and Alive Silver Fir
Annual Radial Increment of Dead vs. Alive Silver Fir
Annual Radial Increment of Norway Spruce and Climatic WaterBalance during July-August of the Five Preceeding Years
Annual Radial Increment of Silver Fir and Climatic Water Balance during July-August of the Five Preceeding Years
Development of radial increment after extreme growth reduction versus the time in years passed since the reduction occurred
Spruce PCAB: left, Fir ABAL: right. The analysis refers to the time period 1936-2002. Only events where radial increment is within the 1-10- (red line), 11-20- (blue) and 21-30-percentile (green) of the ir-index distribution were selected. The annual radial increment data have been standardised into ir-indices using cubic smoothing splines with 50% frequency cut-off of 30 years and normalised to a mean of zero and a standard deviation of one. The lines are the regression models together with the 95% confidence belts (dotted lines).
Development of radial increment after extreme growth reduction
Spruce (PCAB) Elztal. The regression model shows the development of radial increment after extreme growth reduction versus the initial intensity of growth reduction and the time in years passed since the growth reduction occurred. Further explanations see previous figure. Surface plot (left) and corresponding contour plot (right).
Development of radial increment after extreme growth reduction
Fir (ABAL) Elztal. The regression model shows the development of radial increment after extreme growth reduction versus the initial intensity of growth reduction and the time in years passed since the growth reduction occurred. Further explanations see previous figure. Surface plot (left) and corresponding contour plot (right).
Norway Spruce: Terminal Shoot of a 32 m tall Tree.(photo: 28.09.2004, Elzach, Brand)
2002
2003
2004• shoot length reduced• needle number reduced• needle density increased• needle length reduced
Normalstate
Stress Recovery
Func
tiona
lst
ate
Prod
uctio
n
Return to normal state
short-termmedium- to long-term
(acc. to Larcher 2003)
Stress concept: temporary stress, elastic response
time
?
Conclusions: Radial Growth Reduction in 2003 Elevation: low elevation > high elevation
Aspect: north-east > south-west
Drought 2003Working Group 5: Forest Growth
Conclusions: Radial Growth Reduction in 2003 Species: Spruce > Beech
Recovery: Beech > Spruce
Spruce > Fir
Crown Class: intermediate > dominant
Density: no (clear) difference
Drought 2003Working Group 5: Forest Growth
Acknowledgment:Felix Baab, IWW, D
Matthias Dobbertin, WSL, CH
Albert Fehrenbach, IWW, D
André Granier, INRA, F
Stephan Raspe, LWF, D
Rüdiger Unseld, IWW, D
Drought 2003Working Group 5: Forest Growth
Thank you
for your attention!