ERKKI LÄHDE, TIMO PUKKALA, OLAVI
LAIHO,et al.
1.
2.
3.

Optimal uneven-aged (continuous cover)
Optimal even-aged (clear cutting, planting
and high thinning)
Current even-aged (clear cutting, planting
and low thinning)
Referred to as: (1) Uneven, (2) Even, (3) Current
Basal area, m2/ha
Optimal uneven-aged
25
20
15
10
5
0
0
20
40
60
80
Time, years
Current even-aged (low thinnings,
Optimal even-aged (high
thinning, decreasing BA)
increasing BA)
40
Basal area, m2/ha
Basal area, m2/ha
50
100
40
30
20
10
30
20
10
0
0
0
20
40
60
Time, years
80
100
0
20
40
60
Time, years
80
100

Uneven-aged(-sized) management has been
banned for 60 years in Finland and is still so

No research works have supported this

Finns do not like clear-felling
◦ Only 5 % accepts it without reservations
◦ Non-timber values important

Forests are uneven-sized
◦ Starting uneven-aged management would be easy

Large national inventory and field experment data
used for growth modelling

Models used in simulation–optimization system

Net present value (NPV) of 3 benefits maximized

NPV calculated in Pine and Spruce stands for



wood production
bilberry production
sequestration of carbon dioxide






They are all important
They all can be predicted with reasonable accuracy
and quantified in terms of money
The systems were also compared in terms of
Scenic value and
Biological diversity (LLNS index,Lähde et al.1999)
These two latest ones were not included in
optimization
5000
4000
3000
2000
1000
0
-1000
-2000
-3000
-4000
Timber
Carbon
Uneven
Even
Current
Berry
5000
Pine VT
4000
3000
NPV, €/ha
NPV, €/ha
Spruce MT
Uneven
Even
Current
2000
1000
0
-1000
-2000
-3000
-4000
Timber
Carbon
Berry
Pine
25
20
15
10
5
0
Uneven
Even
Current
Mean annual berry harvest, kg/ha
Mean annual berry harvest, kg/ha
Spruce
25
20
15
10
5
0
Uneven
Even
Current




Uneven-aged best in terms of discounted timber
benefit
Uneven-aged and optimal even-aged equal in
terms of carbon sequestration and discounted
carbon benefits
Uneven-aged best in terms of berry yield and
discounted berry benefit
Current even-aged management bad in terms of
discounted timber and berry benefits
Man annual C balance, tn/ha
Uneven
0
-0.05
-0.1
-0.15
-0.2
Even
Pine
Current
Mean annual C balance, tn/ha
Spruce
0.35
0.3
0.25
0.2
0.15
0.1
0.05
0
Uneven
Even
Current
Pine VT
8
7
6
5
4
3
2
1
0
Fuel
Pulp
Log
Uneven Even Current
Mean annual harvest, m3/ha
Mean annual harvest, m3/ha
Spruce MT
8
7
6
5
4
3
2
1
0
Fuel
Pulp
Log
Uneven Even Current
Spruce MT
150
100
50
0
-100
-150
1%
3%
Uneven
Even
Current
5%
Relative NPV, %
Relative NPV, %
100
-50
Pine VT
150
50
0
-50
-100
-150
1%
3%
Uneven
Even
Current
5%



Uneven-aged management superior to both
even-aged management systems with
respect to
-scenic value and
-biological diversity
Spruce MT
Uneven
Even
Current
2
Pine VT
2.5
Scenic beauty index
Scenic beauty index
2.5
1.5
1
0.5
2
1.5
1
Uneven
Even
Current
0.5
0
0
0
40
80
Year
120
0
40
80
Year
120
Spruce MT
15
10
Uneven
Even
Current
5
Pine VT
20
Diversity index
Diversity index
20
0
15
10
Uneven
Even
Current
5
0
0
40
80
Year
120
0
40
80
Year
120



The higher is the number of forest functions
included in the analysis, the clearer is
superiority of uneven-aged management
Main reason: clear felled forest is bad for
most uses for several decades
Discounting accentuates differences
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