scholarly journals Generic Model of Willow Stem Volume: A Meta-Analysis

2021 ◽  
pp. 49-58
Author(s):  
Vladimir А. Usoltsev ◽  
◽  
Andrey А. Paramonov ◽  
Sergey V. Tretyakov ◽  
Sergey V. Koptev ◽  
...  
Keyword(s):  
Forest Management ◽  
Carbon Balance ◽  
Meta Analysis ◽  
Coefficient Of Determination ◽  
Stem Volume ◽  
Generic Model ◽  
Volume Assessment ◽  
Monitoring And Forecasting ◽  
Russian Forests ◽  
Russian Forest

Current scenarios of the consequences of global warming stimulate research on the carbon-depositing capacity of vegetation cover. The stem is the main part of the tree biomass, and the accuracy of its volume assessment determines the possibility of correct monitoring and forecasting of forest resources. In the Russian forest management system, willow was not among the main forest-forming species, and therefore there was no need to develop valuation standards for it. However, due to the increased relevance of assessing the carbon-deposing function of Russian forests and the requirement to take into account the contribution to the carbon balance of all types of vegetation, there is a necessity to develop such standards. The solution can be found in the development of a generic model (or table) that takes into account the morphology of willows within the Salix L. genus and is based on data published in different regions and countries. The object of our research is data on the volume of willow stems, which is published and freely available in Russia, Kazakhstan, Bulgaria, and Norway in the form of tables or regression models. However, the extent to which each local model is applicable in other regions is unknown. To resolve this uncertainty, we used meta-analysis as a statistical procedure that combines the results of several independent studies in order to find a common pattern. As a result, we obtained a generic model of stem volume for the Salix genus, which is characterized by a high coefficient of determination and can be applied to estimate the stem volume of any species of this genus with minimum deviations from the calculated values. The results of the work are aimed at improving the accuracy of accounting deciduous stands during forest management and monitoring activities, valuation of stands on permanent and temporary trial plots. The implementation of unified standards for the use, reproduction, conservation and protection of willow stands with all the diversity of its species will solve a number of practical issues. For citation: Usoltsev V.А., Paramonov А.А., Tretyakov S.V., Koptev S.V., Tsepordey I.S. Generic Model of Willow Stem Volume: A Meta-Analysis. Lesnoy Zhurnal [Russian Forestry Journal], 2021, no. 3, pp. 49–58. DOI: 10.37482/0536-1036-2021-3-49-58

Anrechnung der CO2-Senken des Schweizer Waldes: Grundlagenpapier und Empfehlungen | Accounting of CO2 sinks in Swiss forests. Working paper and recommendations

2005 ◽  
Vol 156 (11) ◽  
pp. 438-441
Author(s):  
Arbeitsgruppe Wald- und ◽  
Holzwirtschaft im Klimaschutz
Keyword(s):  
Forest Management ◽  
Greenhouse Gases ◽  
Climate Policy ◽  
Federal Government ◽  
Kyoto Protocol ◽  
Carbon Balance ◽  
Carbon Sink ◽  
Management Policy ◽  
Working Paper ◽  
Reduction Of Co2

With the ratification of the Kyoto Protocol aimed at reducing greenhouse gases, Switzerland is committed to reducing CO2emissions by 4.2 million tonnes by 2008. The forests in Switzerland could contribute to the country's national carbon balance with maximum 1.8 million tonnes reduction of CO2. With an increased use of the forest the emissions could be reduced by up to 2 million tonnes by the substitution of other materials. With a targeted forest management policy carbon sink reduction and the substitution value of the forest could be balanced against one another. In the framework of climate policy the Federal government should create the legal and organisational conditions for this.

scholarly journals Assessment of Stem Volume on Plots Using Terrestrial Laser Scanner: A Precision Forestry Application

Sensors ◽  
2021 ◽  
Vol 21 (1) ◽  
pp. 301
Author(s):  
Dimitrios Panagiotidis ◽  
Azadeh Abdollahnejad ◽  
Martin Slavík
Keyword(s):  
Norway Spruce ◽  
Laser Scanner ◽  
Estimation Methods ◽  
Coefficient Of Determination ◽  
Stem Volume ◽  
Small Scale ◽  
Terrestrial Laser Scanner ◽  
Precision Forestry ◽  
Total Tree ◽  
European Oak

Timber volume is an important asset, not only as an ecological component, but also as a key source of present and future revenues, which requires precise estimates. We used the Trimble TX8 survey-grade terrestrial laser scanner (TLS) to create a detailed 3D point cloud for extracting total tree height and diameter at breast height (1.3 m; DBH). We compared two different methods to accurately estimate total tree heights: the first method was based on a modified version of the local maxima algorithm for treetop detection, “HTTD”, and for the second method we used the centers of stem cross-sections at stump height (30 cm), “HTSP”. DBH was estimated by a computationally robust algebraic circle-fitting algorithm through hierarchical cluster analysis (HCA). This study aimed to assess the accuracy of these descriptors for evaluating total stem volume by comparing the results with the reference tree measurements. The difference between the estimated total stem volume from HTTD and measured stems was 2.732 m3 for European oak and 2.971 m3 for Norway spruce; differences between the estimated volume from HTSP and measured stems was 1.228 m3 and 2.006 m3 for European oak and Norway spruce, respectively. The coefficient of determination indicated a strong relationship between the measured and estimated total stem volumes from both height estimation methods with an R2 = 0.89 for HTTD and R2 = 0.87 for HTSP for European oak, and R2 = 0.98 for both HTTD and HTSP for Norway spruce. Our study has demonstrated the feasibility of finer-resolution remote sensing data for semi-automatic stem volumetric modeling of small-scale studies with high accuracy as a potential advancement in precision forestry.

scholarly journals Evolution of the hypsometric relationship in Araucaria angustifolia plantations in the mid-south region of Paraná state

CERNE ◽  
2010 ◽  
Vol 16 (3) ◽  
pp. 347-357 ◽  
Author(s):  
Afonso Figueiredo Filho ◽  
Andrea Nogueira Dias ◽  
Sintia Valerio Kohler ◽  
Aline Angélica Verussa ◽  
Ademar Luiz Chiquetto
Keyword(s):  
Coefficient Of Determination ◽  
Generic Model ◽  
Araucaria Angustifolia ◽  
Analysis Method ◽  
Total Height ◽  
The Past ◽  
Satisfactory Performance ◽  
Standard Estimate ◽  
Estimate Error ◽  
The Right

The aim of this study was to assess and model the evolution of the hypsometric relationship in Araucaria angustifolia plantations grown in the 1940's and 1960's in the Irati National Forest, in the mid-south region of Paraná state, Brazil. Using the complete stem analysis method, it was possible to reconstitute the past annual growth of the diameter at 1.3 m (d) and of the total height (h) of a sample of 30 trees, selected so as to cover diametric and age variability. Eleven discs were removed from each tree at 0.1 and 1.3 m and at 15, 25, 35,..., 95% of the total height. Eleven models traditionally used in hypsometric relationships were tested, two of which were considered generic because they involved the age variable. The models were selected based on the Adjusted Coefficient of Determination (R²Adj), Standard Estimate Error (Syx), absolute (m) and relative (%), and on the graphic distribution of residues in percentage. In the models tested by age, no tendencies were observed and erros (Syx) remained below 14.6%, except for ages 5 and 11. However, the coefficients of determination were low, ranging from 0.29 to 0.55. The Curtis generic model (1970), selected to represent the h/d curve for all ages, also presented a satisfactory performance (R²Adj = 0.87 and Syx = 16%), with results similar to those obtained for the models in each age. As age increases, the h/d curve shifts to the right and changes level, remaining steep at the younger ages and more stable and flat as the population nears the end of its cycle.

scholarly journals Une nouvelle approche pour immuniser nos forêts contre l'incertitude (essai)

2018 ◽  
Vol 169 (4) ◽  
pp. 199-202 ◽  
Author(s):  
Christian Messier ◽  
Fanny Maure ◽  
Núria Aquilué
Keyword(s):  
Forest Management ◽  
Global Change ◽  
Conceptual Framework ◽  
Complexity Theory ◽  
Dynamic Systems ◽  
Spatial Network ◽  
New Approach ◽  
The World ◽  
Present Context ◽  
Monitoring And Forecasting

A new approach to immunizing our forests against uncertainty (essay) In the present context of global change, managing our forests is a major challenge, in particular because of the great uncertainty associated with this change. Faced with this new reality, our methods of monitoring and forecasting the developments in our forests are no longer effective enough, so we have to review how we manage our forests. Complexity theory provides a conceptual framework for our approach, which leads us to adopt a more holistic and flexible way of seeing the world when planning our forest management. We must therefore accept that forests are complex and dynamic systems, and for that reason, never completely predictable. By incorporating the functional properties of trees and the complex spatial network of their populations in our forest management, and encouraging greater functional diversity and connectivity, we can immunize the forests against present and future stresses.

scholarly journals Effects of a windthrow disturbance on the carbon balance of a broadleaf deciduous forest in Hokkaido, Japan

2015 ◽  
Vol 12 (23) ◽  
pp. 6837-6851 ◽  
Author(s):  
K. Yamanoi ◽  
Y. Mizoguchi ◽  
H. Utsugi
Keyword(s):  
Forest Management ◽  
Carbon Balance ◽  
Deciduous Forest ◽  
Carbon Sink ◽  
Ecosystem Respiration ◽  
Gross Primary Production ◽  
Co2 Flux ◽  
White Birch ◽  
Eddy Covariance Method ◽  
Area Index

Abstract. Forests play an important role in the terrestrial carbon balance, with most being in a carbon sequestration stage. The net carbon releases that occur result from forest disturbance, and windthrow is a typical disturbance event affecting the forest carbon balance in eastern Asia. The CO2 flux has been measured using the eddy covariance method in a deciduous broadleaf forest (Japanese white birch, Japanese oak, and castor aralia) in Hokkaido, where incidental damage by the strong Typhoon Songda in 2004 occurred. We also used the biometrical method to demonstrate the CO2 flux within the forest in detail. Damaged trees amounted to 40 % of all trees, and they remained on site where they were not extracted by forest management. Gross primary production (GPP), ecosystem respiration (Re), and net ecosystem production were 1350, 975, and 375 g C m−2 yr−1 before the disturbance and 1262, 1359, and −97 g C m−2 yr−1 2 years after the disturbance, respectively. Before the disturbance, the forest was an evident carbon sink, and it subsequently transformed into a net carbon source. Because of increased light intensity at the forest floor, the leaf area index and biomass of the undergrowth (Sasa kurilensis and S. senanensis) increased by factors of 2.4 and 1.7, respectively, in 3 years subsequent to the disturbance. The photosynthesis of Sasa increased rapidly and contributed to the total GPP after the disturbance. The annual GPP only decreased by 6 % just after the disturbance. On the other hand, the annual Re increased by 39 % mainly because of the decomposition of residual coarse-wood debris. The carbon balance after the disturbance was controlled by the new growth and the decomposition of residues. The forest management, which resulted in the dead trees remaining at the study site, strongly affected the carbon balance over the years. When comparing the carbon uptake efficiency at the study site with that at others, including those with various kinds of disturbances, we emphasized the importance of forest management as well as disturbance type in the carbon balance.

Reassessing the role of grazing lands in carbon-balance estimations: Meta-analysis and review

2019 ◽  
Vol 661 ◽  
pp. 531-542 ◽  
Author(s):  
E.F. Viglizzo ◽  
M.F. Ricard ◽  
M.A. Taboada ◽  
G. Vázquez-Amábile
Keyword(s):  
Carbon Balance ◽  
Meta Analysis ◽  
Grazing Lands

Future Shock in Forest Yield Forecasting: The Need for a New Approach

1985 ◽  
Vol 61 (6) ◽  
pp. 503-512 ◽  
Author(s):  
J. P. Kimmins
Keyword(s):  
Forest Management ◽  
Acid Rain ◽  
Atmospheric Chemistry ◽  
Management Practices ◽  
Biomass Accumulation ◽  
Growth Potential ◽  
Stem Volume ◽  
Soil Conditions ◽  
Yield Model ◽  
The Future

The traditional method of predicting future yields of conventional forest products and/or biomass is based on an empirical bioassay of the growth potential of unmanaged stands, or of stands subject to one, or a small number of, management practices. The method employs the historical pattern of stem volume and/or forest biomass accumulation in the form of volume- or biomass-over-age curves. This type of yield predictor, which may be presented as a simple yield table or a more complex mensurational computer yield model, is widely considered to produce believable future yield predictions. However, the predictions will only be accurate if the future environmental conditions and management regimes are similar to those that pertained over the period during which the biomass accumulation on which the yield model is based occurred. This is unlikely because the continued growth of the human population and the resultant loss of forest land will require a great intensification of forest management. The significant changes in management that many believe await forestry in the not-too-distant future in many parts of the world will render such conventional predictions very questionable. In addition, human-induced changes in atmospheric chemistry may result in changes in the climatic (the "green-house gases" problem), canopy or soil conditions (the "acid rain" problem) that determine tree growth.Computer models of forest yield based solely on the simulation of the biological processes that determine tree growth do not at present offer a viable alternative. Either we do not yet know enough to build, or we do not have sufficient resources to develop and calibrate such process models at an adequate level of complexity.What is needed is a generation of hybrid yield models that combine traditional mensurational models with a simulation of those growth-regulating processes that are significantly altered by changing management practices and/or by changing atmospheric chemistry and climate. One such model is FORCYTE: the FORest nutrient Cycling and Yield Trend Evaluator. This is an ecologically-based forest management simulation model that can predict the long-term consequences of a wide variety of forest management practices for the future harvest yield, ecosystem nutrient budgets, economic efficiency and the energy benefit/cost ratio of management. It combines the believability of the traditional approach with the flexibility of ecological and biological process simulation. Present versions of the model focus on the consequences for future production and yield of changes in forest management. However, because of the structure of the model, it is capable of being modified to examine similar consequences of climatic change and alteration in atmospheric chemistry. Progress in the latter area must await clarification of the processes involved in acid rain damage to forests. FORCYTE is also capable, with minor modification, of being used in agriculture and mined land reclamation research and planning. Key words: Yield prediction, FORCYTE.

scholarly journals Timber Volume Estimation Model for Merchantable Tree Species in Sarmi Regency, Papua

Jurnal Wasian ◽  
2016 ◽  
Vol 3 (2) ◽  
pp. 91
Author(s):  
Relawan Kuswandi
Keyword(s):  
Forest Management ◽  
Forest Inventory ◽  
Standing Stock ◽  
Volume Estimation ◽  
Coefficient Of Determination ◽  
Estimation Model ◽  
Timber Volume ◽  
Management Planning ◽  
Forest Management Planning ◽  
Validation Test

Precise forest inventory to estimate standing stock is needed in forest management planning.  Therefore, it is necessary to have proper and reliable tools in estimating merchantable timber volume. This research was intended to build an accurate model to estimate timber volume for  merchantable species in logging concession of PT Wapoga Mutiara Timber, Sarmi Regency.  Regression equation between diameter and length did not have a significant correlation (coefficient of determination, R2 = 6.7 %). The best equation to estimate table tree volume based on validation test in logging concession of PT Wapoga Mutiara Timber was Log V = - 3.34 + 2.16 log d.     

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