scholarly journals Virtual forest stand as a component of sophisticated forestry educational systems

2012 ◽  
Vol 49 (No. 9) ◽  
pp. 419-428 ◽  
Author(s):  
M. Fabrika
Keyword(s):  
Stand Structure ◽  
Forest Stand ◽  
Geographical Information ◽  
Educational Systems ◽  
Individual Tree ◽  
E Learning ◽  
Forest Mensuration ◽  
Internet Environment ◽  
Growth Simulator ◽  
Virtual Reality Model

The paper presents the methodology of virtual stand generation. Virtual stand serves for forestry e-learning as a tool for training of forest tending and demonstration of stand structure and some forest mensuration practices. The model can be connected with growth simulator and geographical information system, or integrated into the Internet environment. In the first part of the paper, the methodology of individual tree visualisation, total stand visualisation, terrain and stand environment visualisation and the principle of user’s interaction with virtual forest are proposed. The Virtual Reality Model Language (VRML 97) was used for these goals. In the second part of the paper, an example of model usage for the training of forest tending is presented.

scholarly journals Financial viability of a fully simulated transformation from even-aged to uneven-aged stand structure in forests of different ages

2021 ◽  
Author(s):  
Lucie Vítková ◽  
Dominik Saladin ◽  
Marc Hanewinkel
Keyword(s):  
Interest Rates ◽  
Stand Structure ◽  
Transformation Process ◽  
Management Approach ◽  
Individual Tree ◽  
Timber Volume ◽  
Growing Stock ◽  
Age Class ◽  
Different Ages ◽  
Growth Simulator

Abstract For the first time, an economic analysis of a fully simulated forest transformation process from even-aged to uneven-aged stand structure using natural regeneration was performed using an individual tree growth simulator. A comparison to a ‘business as usual’ management approach (i.e. age-class scenario) was also made. Norway spruce (Picea abies (L.) Karst.)-dominated forests of different ages were selected for the simulation: forest at thinning stage (52 years; hereafter, ‘younger stand’) and a mature stand (95 years) to explore different starting points for the transformation. The harvested and remaining stand volume showed only little fluctuation over the course of the simulation period in the case of the transformation (uneven-aged) scenario. The age-class scenario, on the other hand, showed peaks and drops in the timber volume. The land expectation values at the end of transformation were higher (i = 1 or 2 per cent) or equal (i = 3 per cent) to those of the age-class scenario for the younger stand. The transformation of younger forests appears to be economically interesting (under interest rates above 2 per cent) as the early revenues of more intensive thinnings achieve an equilibrium growing stock well below the potential maximum growing stock of an even-aged stand. This suggests transformation management to be economically efficient under the given silvicultural and economic conditions. The transformation of mature stands was found to be less economically viable due to the lower holding values for the transformation (uneven-aged) scenario compared with the age-class scenario. However, the holding values of the younger stand were higher for all interest rates compared with the age-class scenario. This study concludes that transformation (uneven-aged) scenario yielded more economically viable silvicultural approach (in the case of younger forests) and a steadier trend in harvested and remaining timber volume showing no major fluctuations. Transformation approach also forms a better foundation where other ecosystem services can be built.

Développement d'un modèle de type arbre appliqué à la croissance des peuplements feuillus irréguliers du sud de la Belgique

1996 ◽  
Vol 26 (10) ◽  
pp. 1838-1848 ◽  
Author(s):  
P. Lejeune
Keyword(s):  
Stand Structure ◽  
Basal Area ◽  
Tree Stand ◽  
Individual Tree ◽  
Growing Period ◽  
Site Characteristics ◽  
Individual Tree Growth ◽  
Forest Mensuration ◽  
Individual Trees ◽  
Changes Over Time

A model predicting circumference growth of individual trees has been developed for mixed irregular stands dominated by Fagussilvatica L. in southeastern Belgium. This model integrates simultaneously tree, stand, and growing site characteristics without considering distances between individual trees. It has a determination coefficient of 40.1% and a residual standard deviation of 0.45 cm/year. Forest mensuration variables considered in the model are circumference, tree social position represented by the total basal area of trees greater than the subject tree, stand basal area, and some index of stand structure corresponding to the ratio of the variance over the mean circumference. The site component is essentially expressed by the length of the growing period. The low accuracy obtained for individual tree growth is relative because the results are used mainly after individual trees have been distributed into size classes. We have been able to show that the introduction of crown description in the model can increase its accuracy. But this modification requires a submodel describing crown changes over time.

Modelling growing stock volume of forest stands with various ALS area-based approaches

2021 ◽  
Author(s):  
Karolina Parkitna ◽  
Grzegorz Krok ◽  
Stanisław Miścicki ◽  
Krzysztof Ukalski ◽  
Marek Lisańczuk ◽  
...  
Keyword(s):  
Laser Scanning ◽  
Mean Squared Error ◽  
Prediction Method ◽  
Forest Stand ◽  
Boosted Regression Trees ◽  
Forest Stands ◽  
Individual Tree ◽  
Growing Stock ◽  
Modelling Techniques ◽  
Stock Volume

Abstract Airborne laser scanning (ALS) is one of the most innovative remote sensing tools with a recognized important utility for characterizing forest stands. Currently, the most common ALS-based method applied in the estimation of forest stand characteristics is the area-based approach (ABA). The aim of this study was to analyse how three ABA methods affect growing stock volume (GSV) estimates at the sample plot and forest stand levels. We examined (1) an ABA with point cloud metrics, (2) an ABA with canopy height model (CHM) metrics and (3) an ABA with aggregated individual tree CHM-based metrics. What is more, three different modelling techniques: multiple linear regression, boosted regression trees and random forest, were applied to all ABA methods, which yielded a total of nine combinations to report. An important element of this work is also the empirical verification of the methods for estimating the GSV error for individual forest stand. All nine combinations of the ABA methods and different modelling techniques yielded very similar predictions of GSV for both sample plots and forest stands. The root mean squared error (RMSE) of estimated GSV ranged from 75 to 85 m3 ha−1 (RMSE% = 20.5–23.4 per cent) and from 57 to 64 m3 ha−1 (RMSE% = 16.4–18.3 per cent) for plots and stands, respectively. As a result of the research, it can be concluded that GSV modelling with the use of different ALS processing approaches and statistical methods leads to very similar results. Therefore, the choice of a GSV prediction method may be more determined by the availability of data and competences than by the requirement to use a particular method.

scholarly journals Forest stand structure and coarse woody debris determine the biodiversity of beetle communities in Mediterranean mountain beech forests

2021 ◽  
pp. e01637
Author(s):  
Francesco Parisi ◽  
Michele Innangi ◽  
Roberto Tognetti ◽  
Fabio Lombardi ◽  
Gherardo Chirici ◽  
...  
Keyword(s):  
Coarse Woody Debris ◽  
Stand Structure ◽  
Woody Debris ◽  
Forest Stand ◽  
Beech Forests ◽  
Forest Stand Structure

scholarly journals Using Airborne Light Detection and Ranging (LIDAR) to Characterize Forest Stand Condition on the Kenai Peninsula of Alaska

2009 ◽  
Vol 24 (2) ◽  
pp. 95-102 ◽  
Author(s):  
Hans-Erik Andersen
Keyword(s):  
Forest Inventory ◽  
Laser Scanning ◽  
Three Dimensional ◽  
Grid Cell ◽  
Forest Stand ◽  
Light Detection And Ranging ◽  
Inventory Analysis ◽  
Light Detection ◽  
Individual Tree ◽  
Kenai Peninsula

Abstract Airborne laser scanning (also known as light detection and ranging or LIDAR) data were used to estimate three fundamental forest stand condition classes (forest stand size, land cover type, and canopy closure) at 32 Forest Inventory Analysis (FIA) plots distributed over the Kenai Peninsula of Alaska. Individual tree crown segment attributes (height, area, and species type) were derived from the three-dimensional LIDAR point cloud, LIDAR-based canopy height models, and LIDAR return intensity information. The LIDAR-based crown segment and canopy cover information was then used to estimate condition classes at each 10-m grid cell on a 300 × 300-m area surrounding each FIA plot. A quantitative comparison of the LIDAR- and field-based condition classifications at the subplot centers indicates that LIDAR has potential as a useful sampling tool in an operational forest inventory program.

scholarly journals Comparative Analysis of Determining the Market Value of Forest Real Properties Using Various Valuation Techniques

2018 ◽  
Vol 26 (1) ◽  
pp. 51-62
Author(s):  
Małgorzata Buśko
Keyword(s):  
Forest Management ◽  
Market Value ◽  
Management Plan ◽  
Forest Resources ◽  
Forest Stand ◽  
Individual Tree ◽  
Market Values ◽  
Significant Difference ◽  
Forest Management Plan ◽  
Survey Approach

Abstract The paper presents procedures for determining market values of forest real properties, with particular emphasis placed on the forest stand. The mixed-approach valuation procedure - land valuation index method - was analyzed. The practical part of the work regarding the valuation of the forest stand introduces the various techniques of valuation and acquisition of data on forest resources used, i.e.: index-based valuation approach and stock survey approach. The subject of the research is part of a forest property, which represents an assessment area, typical of the southern part of Poland, located in the Tenczynek Forest Division. There is a forest management plan for the analyzed property which, together with the assessment descriptions, was used as one of the sources of data for valuation. The second source of data for valuation were direct field surveys, i.e.: geodetic surveys for determining the assessment area and the stock survey approach with individual tree assessment with respect to data on the stand. Based on the research, it may be concluded that both valuation techniques and methods used to capture data on forest resources significantly affect the final value of forest properties. The market value of the stand, determined by the index-based valuation approach, demonstrates a significant difference when compared to the value of the stand determined by the stock survey approach. The forest management plan should only be used as a supplementary material and only to identify site types of forests by property valuers and, partially, together with economic maps, to determine the boundaries of assessment areas.

scholarly journals Stand structure links up canopy processes and forest management

2009 ◽  
Vol 51 (1) ◽  
pp. 40-48
Author(s):  
Toomas Frey
Keyword(s):  
Forest Management ◽  
Stand Structure ◽  
Net Primary Production ◽  
Stand Density ◽  
Tree Height ◽  
Belowground Biomass ◽  
Unit Mass ◽  
Total Biomass ◽  
Individual Tree ◽  
Mean Values

Stand structure links up canopy processes and forest management Above- and belowground biomass and net primary production (Pn) of a maturing Norway spruce (Picea abies (L.) Karst.) forest (80 years old) established on brown soil in central Estonia were 227, 50 and 19.3 Mg ha correspondingly. Stand structure is determined mostly by mean height and stand density, used widely in forestry, but both are difficult to measure with high precision in respect of canopy processes in individual trees. However, trunk form quotient (q2) and proportion of living crown in relation to tree height are useful parameters allowing describe stand structure tree by tree. Based on 7 model trees, leaf unit mass assimilation activity and total biomass respiration per unit mass were determined graphically as mean values for the whole tree growth during 80 years of age. There are still several possible approaches not used carefully enough to integrate experimental work at instrumented towers with actual forestry measurement. Dependence of physiological characteristics on individual tree parameters is the missing link between canopy processes and forest management.

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