Estimation and Uncertainty of the Mixing Effects on Scots Pine—European Beech Productivity from National Forest Inventories Data
Abstract
:1. Introduction
2. Materials and Methods
2.1. Data
2.2. Basal Area Growth Efficiency Models
2.2.1. Relative Density and Species Proportions by Area
2.2.2. Model Fitting
2.2.3. Uncertainty Assessment
3. Results
3.1. Mean Mixing Effects on Basal Area Growth
3.2. Uncertainty of Mixing Effects
4. Discussion
4.1. Species Growth Efficiency According to the General Model
4.2. Total Stand Over-Yielding
4.3. Mixing Effect Uncertainty
4.4. Strengths and Limitations of NFI Databases
5. Conclusions
Author Contributions
Funding
Acknowledgments
Conflicts of Interest
References
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Pine | Beech | Total | ||||||||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
N | dg | Ho | RD | IG | N | dg | Ho | RD | IG | N | dg | Ho | RD | IG | M | |||
Pine | 8109 plots | Mean | 757 | 23.5 | 18.3 | 0.55 | 0.65 | 794 | 22.9 | 18.3 | 0.56 | 0.67 | 45.2 | |||||
Sd | 584 | 8.2 | 7.8 | 0.25 | 0.41 | 595 | 7.8 | 7.8 | 0.25 | 0.42 | 11.9 | |||||||
Min | 28 | 6.8 | 2.8 | 0.10 | 0.01 | 28 | 6.8 | 2.8 | 0.10 | 0.01 | 30.0 | |||||||
Max | 5612 | 67.1 | 42.1 | 1.87 | 3.48 | 5612 | 61.9 | 42.1 | 1.87 | 3.59 | 99.8 | |||||||
Mixtures | 540 plots | Mean | 301 | 29.7 | 19.6 | 0.32 | 0.32 | 489 | 23.1 | 17.3 | 0.25 | 0.33 | 838 | 23.6 | 20.4 | 0.58 | 0.67 | 53.6 |
Sd | 259 | 9.5 | 8.5 | 0.22 | 0.29 | 466 | 14.8 | 6.6 | 0.17 | 0.22 | 551 | 8.3 | 8.2 | 0.25 | 0.36 | 14.9 | ||
Min | 14 | 5.3 | 2.3 | 0.02 | 0.01 | 5 | 7.2 | 4.6 | 0.02 | 0.00 | 75 | 7.4 | 6.1 | 0.11 | 0.07 | 30.5 | ||
Max | 2108 | 57.9 | 43.9 | 1.09 | 2.21 | 2865 | 114.8 | 39.3 | 1.02 | 1.19 | 3701 | 56.6 | 43.9 | 1.46 | 3.02 | 99.0 | ||
Beech | 2460 plots | Mean | 675 | 29.8 | 21.1 | 0.53 | 0.55 | 698 | 29.2 | 21.1 | 0.54 | 0.57 | 64.7 | |||||
Sd | 679 | 14.9 | 6.9 | 0.25 | 0.32 | 688 | 14.4 | 6.9 | 0.25 | 0.33 | 17.9 | |||||||
Min | 10 | 5.5 | 5.6 | 0.10 | 0.01 | 10 | 5.5 | 5.6 | 0.10 | 0.01 | 30.0 | |||||||
Max | 8524 | 155.7 | 47.5 | 1.93 | 2.71 | 8524 | 155.7 | 47.5 | 2.03 | 2.98 | 99.9 |
Pine | Beech | |||
---|---|---|---|---|
Value | Standard Error | Value | Standard Error | |
(Intercept) | 0.8392 | 0.2127 | 0.9262 | 0.2010 |
log(Ho) | 0.2712 | 0.0284 | 0.4887 | 0.0389 |
log(dgsp) | −0.8089 | 0.0242 | −0.6279 | 0.0250 |
log(RD) | 1.4873 | 0.1657 | 0.3879 | 0.0216 |
log(M) | 0.1671 | 0.0470 | −0.2069 | 0.0390 |
log(M)·log(RD) | −0.2285 | 0.0431 | ns | |
RDinter | −3.2002 | 1.1075 | ns | |
log(M)·RDinter | 0.7424 | 0.2811 | 0.1390 | 0.0172 |
R2 marginal | 0.3711 | 0.3588 | ||
R2 conditional | 0.4946 | 0.4002 |
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Condés, S.; Sterba, H.; Aguirre, A.; Bielak, K.; Bravo-Oviedo, A.; Coll, L.; Pach, M.; Pretzsch, H.; Vallet, P.; Del Río, M. Estimation and Uncertainty of the Mixing Effects on Scots Pine—European Beech Productivity from National Forest Inventories Data. Forests 2018, 9, 518. https://doi.org/10.3390/f9090518
Condés S, Sterba H, Aguirre A, Bielak K, Bravo-Oviedo A, Coll L, Pach M, Pretzsch H, Vallet P, Del Río M. Estimation and Uncertainty of the Mixing Effects on Scots Pine—European Beech Productivity from National Forest Inventories Data. Forests. 2018; 9(9):518. https://doi.org/10.3390/f9090518
Chicago/Turabian StyleCondés, Sonia, Hubert Sterba, Ana Aguirre, Kamil Bielak, Andrés Bravo-Oviedo, Lluís Coll, Maciej Pach, Hans Pretzsch, Patrick Vallet, and Miren Del Río. 2018. "Estimation and Uncertainty of the Mixing Effects on Scots Pine—European Beech Productivity from National Forest Inventories Data" Forests 9, no. 9: 518. https://doi.org/10.3390/f9090518