Growth Dynamics of Young Mixed Norway Spruce and Birch Stands in Finland
Abstract
:1. Introduction
2. Materials and Methods
2.1. Study Area
2.2. Data Collection
2.3. Data Analyses
3. Results
3.1. Stand Characteristics
3.2. Individual Tree Growth Dynamics
3.2.1. Diameter Growth
3.2.2. Height Growth
4. Discussion
5. Conclusions
Author Contributions
Funding
Data Availability Statement
Acknowledgments
Conflicts of Interest
References
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Stand | Coordinates | Temperature Sum, d.d. | Age, Years | Site Type | JSM (Year) | C/N Organic | C/N Mineral | |
---|---|---|---|---|---|---|---|---|
North | East | |||||||
1 | 61°22.6′ | 24°48.0′ | 1293 | 23 | OMT | PCT (2009) | 26.1 | 20.0 |
2 | 61°15.3′ | 25°16.6′ | 1271 | 19 | OMT | PCT (2015) | 27.3 | 26.1 |
3 | 61°23.8′ | 25°1.5′ | 1325 | 17 | OMT | PCT (2012) | 24.9 | 22.3 |
4 | 61°22.6′ | 24°48.0′ | 1326 | 24 | MT | EC (2002), PCT (2011) | 24.2 | 24.7 |
5 | 61°23.0′ | 24°57.8′ | 1315 | 24 | MT | PCT (?) | 27.9 | 27.5 |
6 | 61°21.6′ | 25°10.9′ | 1321 | 29 | MT | ? | 30.4 | 27.1 |
7 | 61°20.7′ | 25°5.2′ | 1305 | 19 | MT | PCT (2014) | 25.1 | 23.5 |
8 | 61°37.7′ | 29°18.0′ | 1307 | 19 | OMT | EC (2006), PCT (2014) | 22.2 | 20.4 |
9 | 61°37.6′ | 29°18.2′ | 1307 | 20 | OMT | EC (2006), PCT (2014) | 20.1 | 17.1 |
10 | 61°31.7′ | 29°8.2′ | 1307 | 22 | OMT | PCT (2016) | 24.1 | 24.0 |
Stand | Species | Stem Number, ha−1 | % of Stem Number | Basal Area, m2 ha−1 | Mean dbh, cm | Mean Height, m | Dominant Height, m |
---|---|---|---|---|---|---|---|
1 | All | 1870 | 21.6 | 11.5 | 10.8 | 14.7 | |
spruce | 1000 | 53 | 10.0 | 10.7 | 9.8 | 13.3 | |
silver birch | 130 | 7 | 2.4 | 14.7 | 14.6 | 15.2 | |
downy birch | 270 | 14 | 3.7 | 12.5 | 12.4 | 13.9 | |
2 | All | 1830 | 15.7 | 10.2 | 9.9 | 11.6 | |
spruce | 1210 | 66 | 10.8 | 10.4 | 9.1 | 10.9 | |
silver birch | 550 | 30 | 4.7 | 9.7 | 11.6 | 13.1 | |
downy birch | 60 | 3 | 0.2 | 7.1 | 9.1 | 9.1 | |
3 | All | 2000 | 16.9 | 10.0 | 10.1 | 12.2 | |
spruce | 1300 | 65 | 10.4 | 9.7 | 8.8 | 10.9 | |
silver birch | 600 | 30 | 5.9 | 11.0 | 13.0 | 14.5 | |
downy birch | 60 | 3 | 0.3 | 8.2 | 10.7 | 10.7 | |
4 | All | 910 | 12.9 | 12.2 | 10.6 | 13.4 | |
spruce | 590 | 65 | 11.0 | 14.6 | 10.9 | 13.4 | |
silver birch | 150 | 16 | 1.2 | 9.8 | 11.3 | 12.1 | |
downy birch | 170 | 19 | 0.7 | 6.4 | 8.9 | 10.2 | |
5 | All | 1600 | 19.0 | 11.9 | 12.5 | 17.1 | |
spruce | 840 | 53 | 10.9 | 12.3 | 11.5 | 15.9 | |
silver birch | 300 | 19 | 4.3 | 12.0 | 14.3 | 15.9 | |
downy birch | 370 | 23 | 3.1 | 10.9 | 12.6 | 14.5 | |
6 | All | 2090 | 24.7 | 11.5 | 12.8 | 18.2 | |
spruce | 1240 | 59 | 11.7 | 10.2 | 11.1 | 16.5 | |
silver birch | 460 | 22 | 6.3 | 12.6 | 16.6 | 19.1 | |
downy birch | 20 | 1 | 0.1 | 2.8 | 5.1 | 5.1 | |
7 | All | 1810 | 16.8 | 10.4 | 10.2 | 12.4 | |
spruce | 1140 | 63 | 10.6 | 10.5 | 10.1 | 12.9 | |
silver birch | 190 | 10 | 1.7 | 10.4 | 12.0 | 12.6 | |
downy birch | 140 | 8 | 0.9 | 8.5 | 10.5 | 11.0 | |
8 | All | 1880 | 24.8 | 12.3 | 12.0 | 15.5 | |
spruce | 1240 | 66 | 18.8 | 13.2 | 11.5 | 15.5 | |
silver birch | 340 | 18 | 4.2 | 12.2 | 14.5 | 16.0 | |
downy birch | 180 | 10 | 1.2 | 8.6 | 11.8 | 13.1 | |
9 | All | 1730 | 22.3 | 12.3 | 12.3 | 14.3 | |
spruce | 1000 | 58 | 13.6 | 12.5 | 10.8 | 13.8 | |
silver birch | 520 | 30 | 6.3 | 12.0 | 14.8 | 16.6 | |
downy birch | 180 | 10 | 2.3 | 12.3 | 13.9 | 14.8 | |
10 | All | 2050 | 19.1 | 10.4 | 11.1 | 12.9 | |
spruce | 1140 | 56 | 11.7 | 10.9 | 9.7 | 12.9 | |
silver birch | 760 | 37 | 6.6 | 10.3 | 13.2 | 14.9 | |
downy birch | 150 | 7 | 0.7 | 7.7 | 10.8 | 11.0 |
Effect of Species | Effect of Stand | ||||||
---|---|---|---|---|---|---|---|
Variable | Spruce | Silver Birch | Downy Birch | F (1,29) | p | F (9,29) | p |
Mean dbh, cm | 11.5 ± 1.6a | 11.5 ± 1.9a | 8.5 ± 2.1 | 14.18 | <0.001 | 2.85 | 0.009 |
Mean height, m | 10.3 ± 1.0a | 13.6 ± 1.8 | 10.6 ± 3.0a | 17.05 | <0.001 | 1.99 | 0.061 |
Dominant height, m | 13.6 ± 1.9a | 15.0 ± 2.3a | 11.3 ± 3.4 | 12.49 | <0.001 | 2.57 | 0.017 |
Stem number, ha−1 | 1070 ± 251 | 400 ± 247 | 160 ± 132 | 104.09 | <0.001 | 1.67 | 0.123 |
Basal area, m2 ha−1 | 12.0 ± 2.8 | 4.4 ± 2.6 | 1.3 ± 1.4 | 122.71 | <0.001 | 1.75 | 0.104 |
Volume, m3 ha−1 | 71.2 ± 21.1 | 30.6 ± 19.8 | 8.0 ± 8.5 | 81.85 | <0.001 | 2.32 | 0.029 |
Variable | Spruce | Silver Birch | Downy Birch | F-Test * | p |
---|---|---|---|---|---|
All sample trees in 2020 | N = 160 | N = 126 | N = 34 | ||
Age, years | 20.6 ± 4.4a | 19.5 ± 3.9 | 21.4 ± 2.5a | 4.71 | 0.010 |
Dsh, cm | 14.2 ± 4.5a | 13.2 ± 3.7ab | 12.8 ± 3.8b | 3.49 | 0.032 |
Height, m | 11.2 ± 2.4 | 13.4 ± 2.4 | 12.3 ± 2.2 | 46.26 | <0.001 |
Mean idsh in last 4 years, mm | 7.7 ± 2.9 | 6.4 ± 2.6 | 5.0 ± 2.5 | 25.81 | <0.001 |
Mean ih in last 4 years, cm | 59.5 ± 14.3 | 50.4 ± 11.0a | 46.7 ± 10.5a | 30.32 | <0.001 |
Dominant sample trees in 2020 | N = 80 | N = 72 | N = 26 | ||
Age, years | 21.3 ± 4.8a | 19.9 ± 3.9b | 21.3 ± 2.6ab | 3.61 | 0.029 |
Dsh, cm | 17.3 ± 3.7 | 15.1 ± 3.3 | 13.9 ± 3.5 | 16.79 | <0.001 |
Height, m | 12.2 ± 1.9a | 13.9 ± 2.3 | 12.7 ± 2.0a | 29.07 | <0.001 |
Mean idsh in last 4 years, mm | 9.1 ± 2.5 | 7.2 ± 2.6 | 5.6 ± 2.5 | 44.05 | <0.001 |
Mean ih in last 4 years, cm | 62.4 ± 12.1 | 51.3 ± 9.9 | 46.6 ± 10.6 | 39.37 | <0.001 |
Dominant sample trees in 2010 | N = 80 | N = 72 | N = 26 | ||
Dsh, cm | 7.3 ± 3.2a | 6.6 ± 3.8a | 6.8 ± 2.8a | 1.09 | 0.339 |
Height, m | 5.8 ± 2.0 | 6.7 ± 2.3a | 6.7 ± 1.5a | 15.26 | <0.001 |
All Sample Trees | Dominant Sample Trees | |||
---|---|---|---|---|
Estimate | S.E. | Estimate | S.E. | |
Fixed parameter (species) | ||||
(all species) | 439.7519 | 35.0675 | 492.6726 | 41.8451 |
(silver birch) | −60.0643 | 8.4844 | −92.5508 | 9.6243 |
(downy birch) | −61.6000 | 13.8340 | −102.6199 | 13.7100 |
(all species) | −7.1633 | 1.3532 | −6.9743 | 1.6150 |
(all species) | 0.0782 | 0.0010 | 0.0762 | 0.0013 |
(silver birch) | 0.0233 | 0.0017 | 0.0250 | 0.0021 |
(downy birch) | 0.0020 ns | 0.0028 | 0.0047 ns | 0.0031 |
(all species) | 2.5785 | 0.0957 | 2.6426 | 0.0977 |
(silver birch) | −0.0426 ns | 0.0860 | −0.0658 ns | 0.1117 |
(downy birch) | −0.4710 | 0.1416 | −0.4423 | 0.1585 |
Random parameters | ||||
Stand level | ||||
sd () | 14.1053 | corr () | 13.5546 | corr () |
sd () | 0.2398 | 0.999 | 0.1904 | 0.999 |
Plot level | ||||
sd () | 6.9125 | corr() | 12.2973 | corr () |
sd () | 0.0638 | −1.000 | 0.0153 | −0.999 |
Tree level | ||||
sd () | 66.2934 | corr () | 51.7413 | corr () |
sd () | 0.6505 | 0.434 | 0.6220 | 0.386 |
Error term | ||||
sd () (spruce) | 3.5499 | 4.0240 a | ||
sd () (silver birch) | 3.9616 | 4.0307 a | ||
sd () (downy birch) | 3.7767 | 4.0058 a | ||
Fitting statistics | Random + fixed | Fixed only | Random + fixed | Fixed only |
R2 | 99.6% | 74.1% | 99.6% | 78.9% |
Bias, mm (Bias%) | 0.07 (0.09%) | 0.26 (0.33%) | 0.07 (0.09%) | 0.26 (0.33%) |
RMSE, mm (RMSE%) | 3.49 (4.49%) | 26.55 (34.28%) | 3.49 (4.49%) | 26.55 (34.28%) |
All Sample Trees | Dominant Sample Trees | |||
---|---|---|---|---|
Estimate | S.E. | Estimate | S.E. | |
Fixed parameter (species) | ||||
(all species) | 4426.4543 | 409.7445 | 4752.6402 | 524.6740 |
(silver birch) | −688.0801 | 112.3660 | −632.0077 | 129.1824 |
(downy birch) | −491.1221 | 187.3695 | −677.2739 | 185.6002 |
(all species) | −41.4767 | 15.6635 | −52.8258 | 20.0886 |
(all species) | 0.0323 | 0.0007 | 0.0328 | 0.0010 |
(silver birch) | 0.0169 | 0.0016 | 0.0156 | 0.0019 |
(downy birch) | 0.0046 ns | 0.0025 | 0.0080 | 0.0029 |
(all species) | 1.5163 | 0.0330 | 1.4687 | 0.0431 |
(silver birch) | -- a | -- | −0.0417 ns | 0.0541 |
(downy birch) | -- a | -- | −0.1029 ns | 0.0774 |
(birches) | −0.1168 | 0.0434 | -- | -- |
Random parameters | ||||
Stand level | ||||
sd () | 175.4400 | corr () | 95.5069 | corr () |
sd () | 0.0420 | −0.111 | 0.0621 | −0.138 |
Plot level | ||||
sd () | -- a | corr () | 252.9621 | corr () |
sd () | -- a | -- a | 0.0537 | 0.994 |
Tree level | ||||
sd () | 636.7373 | corr () | 488.6960 | corr ( |
sd () | 0.3605 | 0.700 | 0.3052 | 0.699 |
Error term | ||||
sd () (spruce) | 28.6935 | 27.6291 | ||
sd () (silver birch) | 36.2225 | 35.5614 | ||
sd () (downy birch) | 39.9996 | 37.7442 | ||
Fitting statistics | Random + fixed | Fixed only | Random + fixed | Fixed only |
R2 | 99.4% | 79.3% | 99.4% | 83.2% |
Bias, cm (Bias%) | 0.24 (0.03%) | −4.77 (−0.65%) | 0.20 (0.03%) | −7.37 (−0.94%) |
RMSE, cm (RMSE%) | 32.52 (4.45%) | 185.36 (25.18%) | 31.51 (4.06%) | 171.45 (21.86%) |
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Huuskonen, S.; Lahtinen, T.; Miina, J.; Uotila, K.; Bianchi, S.; Niemistö, P. Growth Dynamics of Young Mixed Norway Spruce and Birch Stands in Finland. Forests 2023, 14, 56. https://doi.org/10.3390/f14010056
Huuskonen S, Lahtinen T, Miina J, Uotila K, Bianchi S, Niemistö P. Growth Dynamics of Young Mixed Norway Spruce and Birch Stands in Finland. Forests. 2023; 14(1):56. https://doi.org/10.3390/f14010056
Chicago/Turabian StyleHuuskonen, Saija, Tuulia Lahtinen, Jari Miina, Karri Uotila, Simone Bianchi, and Pentti Niemistö. 2023. "Growth Dynamics of Young Mixed Norway Spruce and Birch Stands in Finland" Forests 14, no. 1: 56. https://doi.org/10.3390/f14010056
APA StyleHuuskonen, S., Lahtinen, T., Miina, J., Uotila, K., Bianchi, S., & Niemistö, P. (2023). Growth Dynamics of Young Mixed Norway Spruce and Birch Stands in Finland. Forests, 14(1), 56. https://doi.org/10.3390/f14010056