scholarly journals Experiences in Boreal Forest Stem Volume Estimation from Multitemporal C-Band InSAR

10.5772/35102 ◽  
2012 ◽  
Author(s):  
Jan Askne ◽  
Maurizio Santoro
Keyword(s):  
Boreal Forest ◽  
Volume Estimation ◽  
Stem Volume

scholarly journals Constructing single-entry stem volume models for four economically important tree species of Greece

2021 ◽  
Vol 48 (2) ◽  
pp. 136-146
Author(s):  
Panagiotis P. Koulelis ◽  
Kostas Ioannidis
Keyword(s):  
Tree Species ◽  
National Level ◽  
Sustainable Use ◽  
Information Criterion ◽  
Cost Effective ◽  
Volume Estimation ◽  
Stem Volume ◽  
Nonlinear Regression Models ◽  
Cubic Polynomial ◽  
Two Parameter

Abstract Three different nonlinear regression models were tested for their ability to predict stem volume for economically important native tree species in Greece. Τhe models were evaluated using adjusted R square (Adj Rsqr) root mean square error (RMSE) and Akaike information criterion (AICc), where necessary. In general, the quadratic polynomial and cubic polynomial models and the two-parameter power models fit the data well. Although the two-parameter power function fit best for fir, oak, and beech trees, the cubic polynomial model produced the best fit statistics for black pine. Making forest inventory estimates often involves predicting tree volumes from only the diameter at breast height (DBH) and merchantable height. This study covers important gaps in fast and cost-effective methods for calculating the volume of tree species at national level. However, the increasing need for reliable estimates of inventory components and volume changes requires more accurate volume estimation techniques. Especially when those estimates concern the national inventory, those models must be validated using an entire range of age/diameter and site classes of each species before their extended use across the country to promote the sustainable use of forest resources.

Forest stem volume estimation using high-resolution lidar and SAR data

2003 ◽  
Author(s):  
G. Smith ◽  
A. Persson ◽  
J. Hohmgren ◽  
B. Hallberg ◽  
J.E.S. Fransson ◽  
...  
Keyword(s):  
High Resolution ◽  
Volume Estimation ◽  
Stem Volume ◽  
Sar Data

The power function as a simple stem profile examination tool

1991 ◽  
Vol 21 (2) ◽  
pp. 193-198 ◽  
Author(s):  
R. R. Forslund
Keyword(s):  
Power Function ◽  
Volume Estimation ◽  
Stem Volume ◽  
Centre Of Mass ◽  
Centre Of Gravity ◽  
Profile Characteristics ◽  
Volume Estimates ◽  
Quantitative Indicators ◽  
Form Stability ◽  
Mass Form

Formulae are presented for calculating the volume, surface area, centre of gravity, centre of mass, form, taper, and instantaneous slope of the power function. A profile plotting technique is also used that allows visual comparisons between average stem profiles independent of the size and taper of individual stems. The technique is used to demonstrate that the position near 30% of the height from the base of the stem is a position of form stability for volume estimation. Using the paracone profile model (a power function midway between a paraboloid and a cone) with the diameter at the 30% position and the total stem height, individual stem volume estimates within 10% of the true volume (95% confidence) are obtained once again using a sample of 50 yearling aspen (Populustremuloides Michx.). The plotting technique is then applied to the aspen sample, and the average profiles support the hypothesis that juvenile stems may begin life as paraboloids. The average centre of gravity, the average centre of mass, the sectional form, the average form, and the taper of the stems are also examined and are shown to be quantitative indicators of the plotted profile characteristics.

scholarly journals On the Sensitivity of TanDEM-X-Observations to Boreal Forest Structure

2019 ◽  
Vol 11 (14) ◽  
pp. 1644 ◽  
Author(s):  
Jan I. H. Askne ◽  
Henrik J. Persson ◽  
Lars M. H. Ulander
Keyword(s):  
Boreal Forest ◽  
Cloud Model ◽  
Tree Height ◽  
Airborne Lidar ◽  
Stem Volume ◽  
Global Dynamics ◽  
Vegetation Density ◽  
Local Data ◽  
Horizontal Structure ◽  
Model Training

The structure of forests is important to observe for understanding coupling to global dynamics of ecosystems, biodiversity, and management aspects. In this paper, the sensitivity of X-band to boreal forest stem volume and to vertical and horizontal structure in the form of forest height and horizontal vegetation density is studied using TanDEM-X satellite observations from two study sites in Sweden: Remningstorp and Krycklan. The forest was analyzed with the Interferometric Water Cloud Model (IWCM), without the use of local data for model training, and compared with measurements by Airborne Lidar Scanning (ALS). On one hand, a large number of stands were studied, and in addition, plots with different types of changes between 2010 and 2014 were also studied. It is shown that the TanDEM-X phase height is, under certain conditions, equal to the product of the ALS quantities for height and density. Therefore, the sensitivity of phase height to relative changes in height and density is the same. For stands with a phase height >5 m we obtained an root-mean-square error, RMSE, of 8% and 10% for tree height in Remningstorp and Krycklan, respectively, and for vegetation density an RMSE of 13% for both. Furthermore, we obtained an RMSE of 17% for estimation of above ground biomass at stand level in Remningstorp and in Krycklan. The forest changes estimated with TanDEM-X/IWCM and ALS are small for all plots except clear cuts but show similar trends. Plots without forest management changes show a mean estimated height growth of 2.7% with TanDEM-X/IWCM versus 2.1% with ALS and a biomass growth of 4.3% versus 4.2% per year. The agreement between the estimates from TanDEM-X/IWCM and ALS is in general good, except for stands with low phase height.

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