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Lietuvos medynų CO2 pasisavinimo ekonominė analizė / The Economical Analysis of CO2 Sequestration in Lithuania’s Forest StandsLapinskas, Marius 16 June 2006 (has links)
Study object. Forest stands in Lithuania: pine, spruce, birch, aspen, black alder, grey alder, oak, ash and others.
Study aim. To estimate CO2 sequestration, to evaluate and to analyze its dependency on the main tree species, mean annual increment, age.
Methodology. The estimations were made according to formulas stated in book “Algorithm of forest resources reproduction model (1984)”. The formulas allow to calculate CO2 stock per hectare in differrent tree species stands according to annual increment. Also by using Willis&Benson method and data based on calculations made by State Forest Survey Institute according to “IPCC Good Practice Guidance for LULUCF” methodology.
Results. The biggest amount of CO2 is sequestrated in deciduous forest stands: by Zubas et al. method – 17,5 t/ha/year (coniferous – 14,2 t/ha/year); by Willis&Benson method – 10,3 t/ha/year (coniferous – 8,8 t/ha/year); by IPCC Good Practice Guidance for LULUCF method – 8,8 t/ha/year (coniferous – 7,4 t/ha/year). The age classes where annual increment is the highest sequestrate more CO2 than the ones with a lower annual increment. The total estimated value for the sequestrated CO2 of year 2002 in all the forest stands in Lithuania are as stated: by Zubas et al. method – 2,9 mill. Lt; by Willis&Benson method – 1,8 mill. Lt and by IPCC Good Practice Guidance for LULUCF method – 1,5 mill. Lt. For the warmhouse effect reduction the most valuable are tree species with the least economical value of wood... [to full text]
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Ekonomické vyhodnocení škod kůrovcem na lesních porostech v revíru Stříbrné Hutě / Economic evaluation of damages caused by bark beetle on forest stand in the district of Stribrne HuteHEJNÁ, Jana January 2012 (has links)
The aim of the thesis was to evaluate the damage caused by bark beetle on forest stand in the district of Stribne Hute which is managed by Forest Management Tabor. Forest stands are being damaged by various harmful effects which reduce theirs ecological stability. The damage is defined as a reduction of utility value or as a damage caused by adverse effects. Spruce bark beetle (Ips typographus L.) is significant part of entomocenosis and it is being considered as the most serious pest of spruce stands. Data from 2007 - 2012 were processed, it consisted of bark beetle matter production records, evaluation of timber harvest (especially random harvest) and calculation of revenues. The price lists of average values of spruce logs KH and A/B quality was used to calculate revenues from bark beetle matter and standard quality. The comparison of revenues was used to determinate the loss caused by bark beetle. Losses were minimal due to the quantity of bark beetle which did not reach state of emergency.
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Modelo de crescimento, com variáveis ambientais, para o ipê felpudo em diferentes espaçamentos. / Growth model, with ambiental variables, for ipê felpudo in different plantation densities.Clariça Cacciamali de Souza 01 October 2004 (has links)
O Ipê Felpudo (Zehyera tuberculosa (Vell) Bur) é uma espécie nativa, pioneira que possui um alto potencial silvicultural. Essa está ameaçada de extinção devido ao caráter extrativista e predatório da exploração florestal brasileira. A eliminação de complexos ecossistemas florestais por atividades agrícolas, agropecuárias, madeireiras e industriais tem levado a drásticas reduções da base genética dessa essência. O espaçamento é de grande importância para o desenvolvimento das árvores sob aspectos tecnológicos, silviculturais e econômicos. Esse influencia na morfologia e crescimento das árvores. O espaçamento ótimo é aquele que concorrerá para o maior volume do produto e a qualidade almejada. A modelagem florestal inicia-se no inventário de parcelas permanentes que sofrem remedições, pois as florestas são um sistema biológico que está sempre em mudanças e, necessita-se da projeção destas mudanças para que se possa tomar decisões necessárias a fim de ser executado um manejo adequado nesse ecossistema. As decisões de manejo são baseadas em informações sobre as situações atuais e futuras dos povoamentos.Os objetivos desse trabalho são: analisar um experimento com 6 diferentes espaçamentos; definir um modelo de crescimento para a espécie, em função de variáveis do povoamento e climáticas coletadas na Estação Experimental de Linhares, Espírito Santo. / The Ipê Felpudo (Zeyhera tuberculosa (Vell) Bur) is a native and pioneer species, which possesses a high silvicultural potencial. It has been threatened of extinguishing due the intense predatory exraction of the Brazilian forestry exploitation. The elimination of the complex forestry ecosystem for agricultural, farming, lumber and industrial activities has induced to the drastic redutions of its genetic base. Plantation density is one of the most important factor or is the most important factor has a great importance for the development of the trees under technological, sivicultural and economic aspects. It influences in the morphological and trees growth. The excellent plantation density is the one that will concur for the biggest volume of the product and its quality. Forest modeling initiates through the inventory of permanent plots that suffer remeasures, therefore, forests are biological systems that are always changing and requires a projection of theese changes, in order to permit executinge management adjustments in this ecosystem. This decisions are based on information of the current and future situations of the stand. The purposes of this work are: to analyze an experiment with 6 different plantation densities; to define a growth model for this species, with stand and climatic variables, collected in the Experimental Station of Linhares, Espírito Santo.
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Scale challenges in inventory of forests aided by remote sensingKukunda, Collins B. 13 May 2019 (has links)
No description available.
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Contributions to the economic analysis of even-aged silviculture: From simple models to complex analysesHalbritter, Andreas 19 August 2022 (has links)
In managed forests, the enormous complexity of an ecologic system meets a vast range of economic and other impact factors. Thus, to determine, analyze and understand economically optimal stand management is a task which has kept forest economists occupied for the past 200 years. The approach which has been followed since the days of Martin FAUSTMANN is the analysis of models which describe rather specific management scenarios using a set of clearly defined model assumptions. Unfortunately, the applicability of the findings to more general scenarios is limited. On the other side, the possibility of analyzing general management environments with single models is also limited by increasing complexity. Thus, a holistic understanding of optimal forest management is still missing. This statement also holds for the extensive field of optimal even-aged timber production, which essentially consists of only three main components, i.e., planting, thinning and final harvest. Therefore, this dissertation aims to make a contribution to further increase the general understanding of even-aged forest management.
To achieve this goal three steps were taken. First, a qualitative analysis of a combined management plan including decisions on all three basic components is presented based on HALBRITTER and DEEGEN (2015). It provides a discussion of the direct and indirect dependencies between the decision variables of a rotation in a rather classical management environment.
Second, three studies are presented which dissolve some of the classical model assumptions and extend the existing knowledge on even-aged forestry to relevant but more complex mangement questions. HALBRITTER (2015) includes natural regeneration and a shelter period in an even-aged system and explores the borders between the even- and uneven-aged management. Thereby, the influence of natural regeneration and the impact of several age classes were studied. HALBRITTER (2020) drops the assumption of stand homogeneity and investigates stand management under heterogeneous tree growth in which, for example, different social classes of trees are maintained. Lastly, HALBRITTER et al. (2020) extend the classical deterministic management environment in the direction of density-dependent hazard risk. This adds an additional aspect to the thinning and the
rotation decision because, in this scenario, the probability of stand destruction can be controlled by thinning.
As a third step, the studies above were embedded in a patchwork representing a conglomeration of models which are connected and validated by overlapping scopes. Using this approach, a wide range of different management scenarios can be covered by rather simple models. Thus, the complexity of the analysis decreases compared to single models with a more generally applicable framework and the problem of model complexity is mitigated. In addition, the inclusion of reference models with a particular focus on the management components stand establishment, thinning or rotation allows for a clear identification of the relationship between optimal stand management and the characteristics of a scenario. Applied to the qualitative analysis of the four studies above, the approach yields insights which contribute to a better understanding of even-aged forest management.:1. Introduction
2. The FAUSTMANN Framework
2.1 Model Definition
2.2 The FAUSTMANN Model
2.3 Assumptions
2.4 Basic Applications
2.4.1 The Rotation Model
2.4.2 The Thinning Model
2.4.3 The Planting Model
2.4.4 The Uneven-aged Model
3. Problem
4. Methodology
5. The Combined Model
5.1 Model
5.2 Optimal Management
5.3 Impact of Timber Price and Interest Rate
5.4 Discussion in Comparison to the Basic FAUSTMANN Applications
6. Extensions
6.1 Uneven-Aged Extension: The Double-Cohort Model
6.1.1 Even-Aged and Uneven-Aged Stands
6.1.2 Model
6.1.3 Optimal Management
6.1.4 Impact of Timber Price and Interest Rate
6.1.5 Discussion in Comparison to the Basic FAUSTMANN Applications
6.2 Heterogeneous Extension: The Heterogeneous Stand Model
6.2.1 Homogeneous and Heterogenous Stands
6.2.2 Model
6.2.3 Optimal Management
6.2.4 Impact of Timber Price and Interest Rate
6.2.5 Discussion in Comparison to the Basic FAUSTMANN Applications
6.3 Stochastic Extension: The Natural Risk Model
6.3.1 Deterministic and Stochastic Scenarios
6.3.2 Model
6.3.3 Optimal Management
6.3.4 Impact of Timber Price and Interest Rate
6.3.5 Discussion in Comparison to the Basic FAUSTMANN Applications
7. Conclusions
7.1 Optimal Management Strategy
7.1.1 Optimal Planting
7.1.2 Optimal Thinning
7.1.3 Optimal Rotation
7.2 The Patchwork Approach
7.2.1 Applicability of the Patchwork Approach
7.2.2 Limitations of the Patchwork Approach
7.2.3 Comparison to the Holistic Approach
8. Summary
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Effects of forest structure and dynamics on vascular epiphyte assemblages - Functional trait analyses and modelling studiesPetter, Gunnar 02 May 2016 (has links)
No description available.
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Ökonomische Analyse forstlicher Bestandesbehandlung / Economic Analysis of Forest Stand ManagementKoster, Roman 11 September 2020 (has links)
No description available.
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