Thinning Impacts on Even-aged Stands of Eucalyptus in Brazil
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Thinning Impacts on Even-aged Stands of Eucalyptus in Brazil iano S. Nogueira – UFVJM/Brazil Peter L. Marshall – UBC/Ca Valerie Lemay – UBC/Can o Garcia Leite – UFV/Brazil Carlos Chagas Campos – UFV/Brazil June 21, 2010 Missoula, MT Western Mensurationists’ Conference
description
Thinning Impacts on Even-aged Stands of Eucalyptus in Brazil. Gilciano S. Nogueira – UFVJM/Brazil. Peter L. Marshall – UBC/Canada. Helio Garcia Leite – UFV/Brazil. Valerie Lemay – UBC/Canada. João Carlos Chagas Campos – UFV/Brazil. Western Mensurationists’ Conference. - PowerPoint PPT Presentation
Transcript of Thinning Impacts on Even-aged Stands of Eucalyptus in Brazil
Thinning Impacts on Even-aged Stands
of Eucalyptus in Brazil
Gilciano S. Nogueira – UFVJM/Brazil Peter L. Marshall – UBC/CanadaValerie Lemay – UBC/CanadaHelio Garcia Leite – UFV/Brazil
João Carlos Chagas Campos – UFV/Brazil
June 21, 2010 Missoula, MT
Western Mensurationists’ Conference
Introduction
Plantation forest in Brazil: 6.6 million hectares, representing 0.8 % of the land area
From 2004 to 2008 the area in eucalyptus plantation increased by 33.1%, or 1.1 million ha
solid wood products is minimal
Introduction
Advances in wood technology and design have allowed various uses of eucalyptus wood as a solid product
Introduction
The demand for wood from large trees has been supported by illegal harvesting in native forests
Consequently, there are also few studies on the impact of thinning in stands of eucalyptus in Brazil
Introduction
Studies of thinning in eucalyptus are strategic for Brazil, both economically and environmentally
Thinning in eucalyptus forests can help increase Brazilian participation in the global market for solid wood products and may reduce pressure on Brazilian native forests
Introduction
An experiment was established to obtain a database reliable for analyzing the difference among thinning treatments and for developing growth and yield models for thinned eucalyptus stands
Requirements: - Selection of the sample units was deliberate (selective sampling), so that
representation of the medium and extreme site conditions is guaranteed
- The sample units were sufficiently large to faithfully represent the silvicultural practices applied to the remainder of the stand
Objective
To analyze the effect of thinning on growth of stand
variables in eucalyptus forests
Overview of the experiment
- Species: Eucalyptus grandis x Eucalyptus urophylla hybrid
- Location: Northeast region of Bahia State, Brazil
Overview of the experiment
- Planting date: June/July 1993
- Date of installation of the permanent plots: September 1995
- Company: Bahia Specialty Cellulose (BSC) (http://www.bahiaspeccell.com)
- Initial spacing between trees: 3.0 X 3.0 m
- Thinnings accomplished: two selective thinnings, in 1998 and 2004
- Final harvest: at the end of 2007
Experimental Design- based on level-of-growing-stock installation standards
- Located in 3 installations, comprising medium and good quality site conditions
Experimental Design
- Replicated randomized complete block with repeated measures- 6 blocks (two in each installation), each one involving two repetitions;
- 4 treatments, corresponding to different basal area percentages removed in each thinning :
Treatment 1: 20% without pruning;
Treatment 2: 35% without pruning;
Treatment 3: 50% without pruning;
Treatment 4: 35% with pruning up to 6.0 meters;
- Each block contained 8 permanent rectangular plots, with an area of 2,600 m2, totaling 48
plots (6 blocks x 2 repetitions x 4 treatments)
- Layout
Experimental Design
Block 1
Block 2
3 2
2 1
1 4
4 3I II
99,28
204,0 m
3 2
1 4
4 3
2 1III IV
99,28
204,0 m
Block 1 Block 2
Block 2Block 1A
3 2
2 1
1 4
4 3III IV
119.0 m
176.8 m
B
C
Experimental Design
- Replicated randomized complete block with repeated measures- 6 blocks (two in each installation), each one involving two repetitions;
- 4 treatments, corresponding to different basal area percentages removed in each thinning :
Treatment 1: 20% without pruning;
Treatment 2: 35% without pruning;
Treatment 3: 50% without pruning;
Treatment 4: 35% with pruning up to 6.0 meters;
- Each block contained 8 permanent rectangular plots, with an area of 2,600 m2, totaling 48
plots (6 blocks x 2 repetitions x 4 treatments)
- Plots were buffered by a few rows of trees on each side
Marked boundaries of a plot
Measurement Year ofmeasurement
Age (month)
Age (year) Note
1 1995 27 2.3 before 1st thinning2 1996 40 3.3 before 1st thinning3 1997 50 4.2 before 1st thinning; 1st stem analysis (6 trees per dbh class)4 1998
61 5.1after 1st thinning
5 1999 75 6.3 after 1st thinning6 2000 87 7.3 after 1st thinning7 2001 100 8.3 after 1st thinning8 2002 111 9.3 after 1st thinning9 2003 124 10.3 after 1st thinning
10 2004 136 11.3 after 1st thinning11 2005 147 12.3 after 2nd thinning12 2006 157 13.1 after 2nd thinning13 2007 164 13.7 after 2nd thinning; 2nd stem analysis (6 trees per dbh class)
- Data
Measurements
After 1st thinning (61 months)
After 1st thinning (87 months)
MeasurementsAfter 1st thinning (101 months)
After 2nd thinning (165 months)
Volume equation
HtLndbhLnVtLn 23523.1751165.1-10.28859 998.02 R
outside bark:
inside bark:
HtLndbhLnVtLn 22368.174249.1-10.39158 998.02 R
Volume equation
Distri b u ti o n o f Ra w re si d u a l s
E xp e cte d No rm a l
-0 .3 0 -0 .2 5 -0 .2 0 -0 .1 5 -0 .1 0 -0 .0 5 0 .0 0 0 .0 5 0 .1 0 0 .1 5 0 .2 00
2 0
4 0
6 0
8 0
1 0 0
1 2 0
1 4 0
1 6 0
1 8 0
2 0 0
No of obs
P re d i cte d vs. O b se rve d V a l u e sD e p e n d e n t va ria b le : L n V t ib
-5 .0 -4 .5 -4 .0 -3 .5 -3 .0 -2 .5 -2 .0 -1 .5 -1 .0 -0 .5 0 .0
P re d icte d V a lu e s
-5 .0
-4 .5
-4 .0
-3 .5
-3 .0
-2 .5
-2 .0
-1 .5
-1 .0
-0 .5
0 .0
Observed V
alues
9 5 % co n f id e n ce
P re d i cte d vs. Re si d u a l S co re sDe p en d e n t va ri ab l e : L n V tib
-5 .0 -4 .5 -4 .0 -3 .5 -3 .0 -2 .5 -2 .0 -1 .5 -1 .0 -0 .5 0 .0
P re d i cte d V a lu e s
-0 .2 5
-0 .2 0
-0 .1 5
-0 .1 0
-0 .0 5
0 .0 0
0 .0 5
0 .1 0
0 .1 5
0 .2 0
0 .2 5
Residuals
9 5 % co n f i de n ce
Di stri b u ti o n o f Ra w re sid u a l s E xp e cte d No rm a l
-0 .3 0 -0 .2 5 -0 .2 0 -0 .1 5 -0 .1 0 -0 .0 5 0 .0 0 0 .0 5 0 .1 0 0 .1 5 0 .2 0 0 .2 50
2 0
4 0
6 0
8 0
1 0 0
1 2 0
1 4 0
1 6 0
1 8 0
2 0 0
No of obs
P re d i cte d vs. O b se rve d V a l u e sDe p e n d e n t va ria b l e : L n V to b
-4 .5 -4 .0 -3 .5 -3 .0 -2 .5 -2 .0 -1 .5 -1 .0 -0 .5 0 .0 0 .5
P re d ic te d V a lu e s
-4 .5
-4 .0
-3 .5
-3 .0
-2 .5
-2 .0
-1 .5
-1 .0
-0 .5
0 .0
0 .5
Observed V
alues
9 5 % co n f id e n ce
P re d i c te d vs. Re sid ua l S co re sDe p e n d e n t va ri a b le : L n V to b
-5 -4 -3 -2 -1 0
P re d i cte d V a l ue s
-0 .2 5
-0 .2 0
-0 .1 5
-0 .1 0
-0 .0 5
0 .0 0
0 .0 5
0 .1 0
0 .1 5
0 .2 0
0 .2 5
Residuals
9 5 % co n fid e n ce
outside bark
inside bark
Height equation
dbhdbhLn
SISILnAgeAgeLnHtLn-0.016830.64171
-0.4935512.928360.00231-0.42280-29.32738
97.02 R
Installation A
dbhdbhLn
SISILnAgeAgeLnHtLn0.01233-0.54414
0.6872217.218170.00238-0.45930-38.23811
dbhdbhLn
SISILnAgeAgeLnHtLn0.03013-0.81710
0.4116412.671100.00774-0.85823-32.40495
Installation B
Installation C
97.02 R
98.02 R
Height equation
Distri b u ti o n o f Ra w re si d u a l s E xp e cte d No rm a l
-0 .2 0 -0 .1 6 -0 .1 2 -0 .0 8 -0 .0 4 0 .0 0 0 .0 4 0 .0 8 0 .1 2 0 .1 6 0 .2 00
1 0 0
2 0 0
3 0 0
4 0 0
5 0 0
6 0 0
7 0 0
8 0 0
No of obs
P re d i cte d vs. O b se rve d V a lu e s
De p e n d e n t va ri a b l e : L n Ht
2 .0 2 .2 2 .4 2 .6 2 .8 3 .0 3 .2 3 .4 3 .6
P re d i cte d V a l u e s
2 .0
2 .2
2 .4
2 .6
2 .8
3 .0
3 .2
3 .4
3 .6
Observed V
alues
9 5 % co n f i d e n ce
A
Distri b u ti o n o f Ra w re si d u a l s E xp e cte d No rm a l
-0 .2 0 -0 .1 6 -0 .1 2 -0 .0 8 -0 .0 4 0 .0 0 0 .0 4 0 .0 8 0 .1 2 0 .1 6 0 .2 00
1 0 0
2 0 0
3 0 0
4 0 0
5 0 0
6 0 0
7 0 0
8 0 0
No of obs
P re d i cte d vs. O b se rve d V a lu e sDe p e n d e n t va ri a b le : L n Ht
2 .0 2 .2 2 .4 2 .6 2 .8 3 .0 3 .2 3 .4 3 .6
P re d i cte d V a lu e s
2 .0
2 .2
2 .4
2 .6
2 .8
3 .0
3 .2
3 .4
3 .6
Observed V
alues
9 5 % co n fi d e n ce
P re d ic te d vs. Re si d u a l S co re sDe p e n d e n t va ria b le : L n Ht
2 .0 2 .2 2 .4 2 .6 2 .8 3 .0 3 .2 3 .4 3 .6
P re d i cte d V a lu e s
-0 .2 0
-0 .1 5
-0 .1 0
-0 .0 5
0 .0 0
0 .0 5
0 .1 0
0 .1 5
0 .2 0
Residuals
9 5 % co n fi d e n ce
B
P re d i cte d vs. Re sid u a l S co re s
2 .0 2 .2 2 .4 2 .6 2 .8 3 .0 3 .2 3 .4 3 .6
Predic ted Values
-0 .2 0
-0 .1 5
-0 .1 0
-0 .0 5
0 .0 0
0 .0 5
0 .1 0
0 .1 5
0 .2 0
Residuals
9 5 % co n fi d e n c e
Height equation
Distri b u ti o n o f Ra w re si d u a l s
E xp e cte d No rm a l
-0 .2 0 -0 .1 6 -0 .1 2 -0 .0 8 -0 .0 4 0 .0 0 0 .0 4 0 .0 8 0 .1 2 0 .1 6 0 .2 00
5 0
1 0 0
1 5 0
2 0 0
2 5 0
3 0 0
3 5 0
4 0 0
No of obs
P re d i cte d vs. O b se rve d V a lu e sDe pe n d e n t va ri a b le : L n H t
1 .8 2 .0 2 .2 2 .4 2 .6 2 .8 3 .0 3 .2 3 .4 3 .6
P re d i cte d V a lu e s
1 .8
2 .0
2 .2
2 .4
2 .6
2 .8
3 .0
3 .2
3 .4
3 .6
Observed V
alues
9 5 % co n fi d e n ce
P re d i cte d vs. Re sid u a l S co re s
De p e n d e n t va ri a b le : L n Ht
2 .0 2 .2 2 .4 2 .6 2 .8 3 .0 3 .2 3 .4 3 .6
P re d i c te d V a lu e s
-0 .2 0
-0 .1 5
-0 .1 0
-0 .0 5
0 .0 0
0 .0 5
0 .1 0
0 .1 5
0 .2 0
Residuals
9 5 % co n fid e n ce
C
Growth trendMean per treatment Individual values
Growth trendsMean per treatment Individual values
Growth trendsMean per treatment Individual values
Growth trendsMean per treatment Individual values
Analysis
Variables: - periodic monthly increment (absolute): total height, dominant height,
quadratic mean diameter and volume per tree - periodic monthly increment (percentage): basal area per hectare and
volume per hectare
Periods: A and B1
(61 to 87)3
(147 to 165)2
(87 to 137)1
(61 to 87)2
(61 to 87)
C
Analysis
Anova: Mixed linear model, with thinning as the whole plot factor and period as the split-plot factor
Random effect: block block*thinning Repetition(block*thinning) period period*thinning
Fixed effect: thinning
Pairwise comparisons: Bonferroni test
Effect on periodic increment of average total height
A B C
A: only thinning 35% and thinning 35% + pruning were equal
B and C : Only thinning 20% was different from the other treatments
There is thinning effect
Effect on periodic increment of dominant height
No thinning effect
Effect on periodic increment of quadratic mean diameter
A B C
A, B and C: only thinning 35% and thinning 35% + pruning were equal
There is thinning effect
Effect on periodic increment of basal area per hectare
A B C
A, B and C: only thinning 35% and thinning 35% + pruning were equal
There is thinning effect
Effect on periodic increment of volume per hectare
A B C
A, B and C: only thinning 35% and thinning 35% + pruning were equal
There is thinning effect
Effect on periodic increment of volume per tree
A
A, B and C: only thinning 35% and thinning 35% + pruning were equal
There is thinning effect
B C
Conclusion
No surprise!
Conclusion
Thinning affected the growth of total height, diameter, basal area per hectare, total volume per tree and total volume per hectare, but did not affect the growth of dominant height
Thinning prevented regular tree mortality
Prunning did not affect the growth trend of the variables analyzed
