Modeling individual tree height to diameter ratio for Norway spruce and European beech in Czech Republic

The article aims to evaluate the research provenance plot established in 1980 in locality No. 214 – Hrubá Skála (in the north of the Czech Republic), where nine provenances of grand fir (Abies grandis (Douglas ex D. Don) Lindley) provided in the framework of the International Union of Forest Research Organizations project, and one provenance of grand fir, Norway spruce, silver fir and Douglas-fir from a standard commercial source are tested. We present the results of tree height, stem DBH, stem volume production and health status after 36 years. The results correspond with similar experiments in the Czech Republic and abroad and suggest that grand fir provenances from Vancouver Island (British Columbia, Canada) and the Washington (USA) State coastal region show the best production features, while the Oregon Cascades, Idaho and Montana provenances grow more slowly. Comparison with other tree species indicates that the production of grand fir at the investigated age exceeds the production of both Norway spruce and silver fir, and equalizes or gently exceeds even Douglas-fir.

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The Effect of Crown Social Class on Bark Thickness and Sapwood Moisture Content in Norway Spruce

Forests ◽

10.3390/f11121316 ◽

2020 ◽

Vol 11 (12) ◽

pp. 1316

Author(s):

Luka Krajnc ◽

Jožica Gričar

Keyword(s):

Social Class ◽

Moisture Content ◽

Norway Spruce ◽

Research Study ◽

Physiological State ◽

Tree Height ◽

Social Classes ◽

Bark Thickness ◽

Individual Tree ◽

The Relationship

The research study examined the effect of tree properties (crown social class, diameter at breast height (DBH), and tree height) on bark thickness (BT) and sapwood moisture content (SMC) in Norway spruce (Picea abies (L.) H. Karst.). Both examined variables were shown to be positively affected by DBH and tree height. The relationship between DBH and SMC varied among crown social classes, while the relationship between DBH and BT was relatively constant across crown social classes. Crown social class had a relatively small effect on BT and SMC, having a more pronounced effect on SMC than on BT. The relationship between tree height and BT did not vary across crown social classes, while the relationship between SMC and tree height was found to change slightly across crown social classes. Measurements of BT and SMC in the field are affordable, fast, and easy to use. Both variables could potentially be used to improve predictions of bark beetle attacks, as they reflect the physiological state of an individual tree.

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Modeling individual tree height growth of Norway spruce and Scots pine from national forest inventory data in Norway

Scandinavian Journal of Forest Research ◽

10.1080/02827581.2016.1269944 ◽

2016 ◽

Vol 32 (6) ◽

pp. 501-514 ◽

Cited By ~ 5

Author(s):

Ram P. Sharma ◽

Andreas Brunner

Keyword(s):

Norway Spruce ◽

Forest Inventory ◽

Tree Height ◽

National Forest Inventory ◽

Height Growth ◽

National Forest ◽

Inventory Data ◽

Individual Tree ◽

Forest Inventory Data ◽

Tree Height Growth

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The accuracy of estimating individual tree variables with airborne laser scanning in a boreal nature reserve

Canadian Journal of Forest Research ◽

10.1139/x04-055 ◽

2004 ◽

Vol 34 (9) ◽

pp. 1791-1801 ◽

Cited By ~ 116

Author(s):

M Maltamo ◽

K Mustonen ◽

J Hyyppä ◽

J Pitkänen ◽

X Yu

Keyword(s):

Norway Spruce ◽

Scots Pine ◽

Laser Scanning ◽

Stand Structure ◽

Tree Height ◽

Heterogeneous Structure ◽

Mixed Stands ◽

Individual Tree ◽

Tree Layer ◽

Pine Trees

This study examines the ability of high-density laser scanning to produce single-tree estimates in mixed stands of heterogeneous structure. Individual trees were detected from a constructed digital canopy height model by locating local maxima of the height values. The reference material comprised accurately measured field data for 10 mapped sample plots containing Norway spruce (Picea abies (L.) Karst.), Scots pine (Pinus sylvestris L.), and different birches. To verify the accuracy of height measurements of single trees in more detail, the height of 29 Scots pine trees and their annual shoots of the last few years was carefully measured with a tacheometer and a glass fibre rod. The considered variables were the proportion of detected trees and tree height. As more than 80% of the dominant trees were detected, the results indicated that laser scanning can accurately describe the trees of the dominant tree layer. Because of the dense understorey tree layer in most of the sample plots, about 40% of all trees were detected. On the plot level, the stand structure affected the accuracy of the results considerably. The scanning-based tree height was most accurate for Norway spruce and least accurate for birches. The height of the separately measured 29 Scots pine trees was obtained with an accuracy of ±50 cm or better.

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Estimation of Genetic Parameters and Selection of Superior Genotypes in a 12-Year-Old Clonal Norway Spruce Field Trial after Phenotypic Assessment Using a UAV

Forests ◽

10.3390/f11090992 ◽

2020 ◽

Vol 11 (9) ◽

pp. 992

Author(s):

Mateusz Liziniewicz ◽

Liviu Theodor Ene ◽

Johan Malm ◽

Jens Lindberg ◽

Andreas Helmersson ◽

...

Keyword(s):

Norway Spruce ◽

Field Trial ◽

Measurement Techniques ◽

Tree Height ◽

Tree Breeding ◽

Breeding Program ◽

Average Height ◽

Individual Tree ◽

Breeding Populations ◽

Additive Regression

Height is a key trait in the indices applied when selecting genotypes for use in both tree breeding populations and production populations in seed orchards. Thus, measurement of tree height is an important activity in the Swedish Norway spruce breeding program. However, traditional measurement techniques are time-consuming, expensive, and often involve work in bad weather, so automatization of the data acquisition would be beneficial. Possibilities for such automatization have been opened by advances in unmanned aerial vehicle (UAV) technology. Therefore, to test its applicability in breeding programs, images acquired by a consumer-level UAV (DJI Phantom 4 Pro V2.0) system were used to predict the height and breast height diameter of Norway spruce trees in a 12-year-old genetic field trial established with 2.0 × 2.0 m initial spacing. The tree heights were also measured in the field using an ultrasonic system. Three additive regression models with different numbers of predictor variables were used to estimate heights of individual trees. On stand level, the average height estimate derived from UAV data was 2% higher than the field-measured average. The estimation of family means was very accurate, but the genotype-level accuracy, which is crucial for selection in the Norway spruce breeding program, was not high enough. There was just ca. 60% matching of genotypes in groups selected using actual and estimated heights. In addition, heritability values calculated from the predicted values were underestimated and overestimated for height and diameter, respectively, with deviations from measurement-based estimates ranging between −19% and +12%. However, the use of more sophisticated UAV and camera equipment could significantly improve the results and enable automatic individual tree detection.

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Generalized Nonlinear Mixed-Effects Individual Tree Crown Ratio Models for Norway Spruce and European Beech

Forests ◽

10.3390/f9090555 ◽

2018 ◽

Vol 9 (9) ◽

pp. 555 ◽

Cited By ~ 7

Author(s):

Ram Sharma ◽

Zdeněk Vacek ◽

Stanislav Vacek

Keyword(s):

Norway Spruce ◽

Model Fitting ◽

Basal Area ◽

European Beech ◽

Logistic Function ◽

Mixed Effects ◽

Mixed Effects Model ◽

Individual Tree ◽

Mixed Effects Modeling ◽

Species Mixture

Tree crowns are commonly measured to understand tree growth and stand dynamics. Crown ratio (CR—crown depth-to-total height ratio) is significantly affected by a number of tree- and stand-level characteristics and other factors as well. Generalized mixed-effects CR models were developed using a large dataset (measurements from 14,669 trees of Norway spruce (Picea abies (L.) Karst.) and European beech (Fagus sylvatica (L.)) acquired from permanent research plots in various parts of the Czech Republic. Among several tree- and stand-level variables evaluated, diameter at breast height, height to crown base, dominant height, basal area of trees larger in diameter than a focal tree, relative spacing index, and variables describing the effects of species mixture and canopy height differentiation significantly contributed to CR variation. We included sample-plot-level variations caused by randomness in the data and other stochastic factors into the CR models using the mixed-effects modeling approach. The logistic function, which predicts the values between 0 and 1, was chosen to develop the generalized CR mixed-effects model. A large proportion of the CR variation (R2adj ≈ 0.63 (Norway spruce); 0.72 (European beech)) was described by generalized mixed-effects model without significant residual trends. Testing the CR model against a part of the model fitting dataset confirmed its high prediction precision. Our CR model can be useful for growth simulation using inventory databases that lack crown measures. Other potential implications of our CR models in forest management are mentioned in the article.

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Transgressive overyielding in mixed compared with pure stands of Norway spruce and European beech in Central Europe: evidence on stand level and explanation on individual tree level

European Journal of Forest Research ◽

10.1007/s10342-008-0215-9 ◽

2008 ◽

Vol 128 (2) ◽

pp. 183-204 ◽

Cited By ~ 177

Author(s):

Hans Pretzsch ◽

Gerhard Schütze

Keyword(s):

Norway Spruce ◽

Central Europe ◽

European Beech ◽

Tree Level ◽

Individual Tree

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Tree biomass allometry during the early growth of Norway spruce (Picea abies) varies between pure stands and mixtures with European beech (Fagus sylvatica)

Canadian Journal of Forest Research ◽

10.1139/cjfr-2017-0177 ◽

2018 ◽

Vol 48 (1) ◽

pp. 77-84 ◽

Cited By ~ 6

Author(s):

Ioan Dutcă ◽

Richard Mather ◽

Florin Ioraş

Keyword(s):

Picea Abies ◽

Norway Spruce ◽

Fagus Sylvatica ◽

Aboveground Biomass ◽

European Beech ◽

Mixed Stand ◽

Pure Stand ◽

Tree Biomass ◽

Mixed Stands ◽

Individual Tree

In this paper, we report an investigation of how forest stand mixture may affect biomass allometric relationships in Norway spruce (Picea abies (L.) Karst.). Analysis of aboveground biomass data was conducted for 50 trees: 25 sample trees from a pure Norway spruce stand and 25 from a mixed stand of Norway spruce with European beech (Fagus sylvatica L.). ANCOVA results demonstrated that individual-tree biomass allometry of the pure stand significantly differed from that of the mixed stand. Allometric characteristics depended on the biomass component recorded and the type of biomass predictor used. When predicted by diameter at breast height and (or) height, the total aboveground biomass of mixed-stand trees was significantly less than that for pure-stand trees. This “apparent” lower aboveground biomass was attributed to the lower branch and needle biomass proportions of trees growing in mixed stand. The findings indicate that caution should be exercised when applying biomass allometric models developed from pure stands to predict tree biomass in mixed stands (and vice versa), as such data treatment may introduce significant bias.

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