scholarly journals Scots Pine Stem Parameters in Sites with Different Stand Densities in Lithuania

Forests ◽  
2020 ◽  
Vol 11 (7) ◽  
pp. 716
Author(s):  
Lina Beniušienė ◽  
Benas Šilinskas ◽  
Ričardas Beniušis ◽  
Marius Aleinikovas ◽  
Edmundas Petrauskas ◽  
...  

Background and Objectives: The aim of this study was to determine the effects of different stand densities and thinning regimes on stem quality parameters, mainly branch characteristics, of Scots pine (Pinus sylvestris L.) trees. The study provides some input to the discussion about Scots pine stem quality responses to different forest management practices in relatively young stands. Materials and Methods: Total tree height, height to the lowest live and dead branch, diameter at breast height (DBH), and diameter of all branches from the whorls located up to 6 m from the ground were measured. The linear regression models to predict branch diameter, as the main parameter for the stem quality assessment, were developed based on stand density and stem parameters. Results and Conclusions: DBH, branch diameter and number of branches up to 6-m stem height were significantly higher in the stands with the lowest density. These stem parameters showed a relatively clear downward trend from the lowest to the highest stand densities. The main identified variables which significantly affected stem quality, were branch diameter and diameter of the thickest branch in the bottom part of the stem, at least up to 3-m stem height. For practical use, the best fitted model was estimated when stand density, DBH, and branch diameter up to 3-m height were included in a single equation. The developed model for branch diameter could be used as a forest management tool for managing stem-wood quality.

Forests ◽  
2021 ◽  
Vol 12 (2) ◽  
pp. 201
Author(s):  
Lina Beniušienė ◽  
Edmundas Petrauskas ◽  
Marius Aleinikovas ◽  
Iveta Varnagirytė-Kabašinskienė ◽  
Ričardas Beniušis ◽  
...  

Background and Objectives: The study aimed to determine the changes of the main stem and branch parameters of Norway spruce (Picea abies (L.) H. Karst) trees under different stand densities. More specifically, the objective was to develop the models for the determination of branch diameter in 0–6 m log from root collar, taken as one of the parameters directly influencing the stem quality. The study continues a piece of research on stem and branch parameters’ responses to different stand density (SD) in the plantations of coniferous tree species in Lithuania. Materials and Methods: The following key parameters were measured in this study: total tree height, diameter at breast height, height to the lowest live branch, height to the lowest dead branch, and diameter of all branches in 0–6 m log. The linear regression models to predict branch diameter in 0–6 m log were developed based on stand density (SD), tree characteristics (tree diameter at breast height, DBH; and tree height, H) and other related stem and branch parameters. Results and Conclusions: Directly measured tree DBH, branch diameters and number of branches in 0–6 m log decreased significantly with the increasing SD. In the 0–6 m log, the branch diameter and the diameter of the thickest branch were identified as the main parameters related to stem quality. The best fitted models, developed including SD, tree DBH, branch diameter, and diameter of the thickest branch in 0–3 m log, can be proposed as a predictor for stem-wood quality for Norway spruce in hemiboreal forest zone.


CERNE ◽  
2013 ◽  
Vol 19 (3) ◽  
pp. 509-515 ◽  
Author(s):  
Luciano Farinha Watzlawick ◽  
Marcos Vinicius Winckler Caldeira ◽  
Tiago de Oliveira Godinho ◽  
Rafaelo Balbinot ◽  
Jonathan William Trautenmüller

This study aimed to estimate biomass and organic carbon in stands of Pinus taeda L. at different ages (14, 16, 19, 21, 22, 23 and 32 years) and located in the municipality of General Carneiro (PR). In order to estimate biomass and organic carbon in different tree components (needles, live branches, dead branches, bark and stem wood), the destructive quantification method was used in which seven trees from each age category were randomly sampled across the stand. Stocks of biomass and organic carbon were found to vary between the different age categories, mainly as a result of existing dissimilarities between ages in association with forest management practices such as thinning, pruning and tree density per hectare.


1998 ◽  
Vol 28 (11) ◽  
pp. 1686-1696 ◽  
Author(s):  
Harri Mäkinen ◽  
Francis Colin

A total of 19 thinning experiments were performed in southern and central Finland to study branchiness of Scots pine (Pinus sylvestris L.). Data were collected from 229 trees of different ages and canopy positions growing on sites of different fertility and thinned to different stand densities. They were used to construct models for predicting vertical trends of branch angle and branch diameter along the stem. By using the variance component model, it was possible to separate the stand-, plot-, and tree-level variations of the dependent variables. However, as the random stand and plot effects were small, they were ignored. The random tree effect of the branch angle model was slightly higher compared with the random tree effect of the branch diameter model. Branch angle increased rapidly in the upper part of the crown, but the increase levelled off in the lower part of the stem. Branch diameter increased from the stem apex to the lower part of the crown and then decreased again towards the base of the tree. Stand density measures were significant variables in the models of branch angle and branch diameter. However, they could be excluded without loss of accuracy if variables describing dimensions of the tree were used as independent variables. Relative crown length and stem diameter were adequate tree-level variables for describing branch characteristics. Validation of the models constructed without variables describing stand density revealed no biased behaviour with respect to stand density. It was concluded that branch characteristics can be predicted from the measurement of some tree-level variables without detailed knowledge of the stand history.


Forests ◽  
2020 ◽  
Vol 11 (2) ◽  
pp. 240 ◽  
Author(s):  
Andrzej Węgiel ◽  
Krzysztof Polowy

Background and Objectives: The continuous increase in the amount of atmospheric CO2 is a factor that significantly contributes to global warming. Forests can be used to mitigate climate change by absorbing carbon and storing it. Scots pine (Pinus sylvestris L.) is the most abundant tree species in Polish forests and can substantially aid carbon accumulation. The aim of the study was to determine the carbon content in the dry mass of various parts of Scots pine trees and to evaluate the relationship between the accumulation of carbon in aboveground tree biomass and some stand parameters. Materials and Methods: The research was carried out in 20 even-aged (81–90 years old) Scots pine stands in northwestern Poland (Drawno Forest District). The densities of these stands ranged from 476 to 836 trees per hectare. The aboveground biomass was calculated as the sum of the following tree compartments: stem (wood and bark), dead branches, thick branches, thin branches and needles. The carbon content and storage in these compartments was determined. Results: The mean carbon content was lowest in stem wood (47.0%) and highest in needles (50.3%). No correlation between the stand density and the level of carbon stored in the aboveground biomass of Scots pines was found.


1999 ◽  
Vol 29 (5) ◽  
pp. 585-594 ◽  
Author(s):  
Harri Mäkinen

Branch development of Scots pine (Pinus sylvestris L.) was studied in 19 thinning experiments in southern and central Finland. Data were collected from 229 trees on sites of different fertility with different stand density, age, and canopy position. Stem sections that included the thickest branch or knot of the whorl were sawn out from the whorls below the lowest living and dead whorl. The stem sections were dissected and the years of birth, suppression, death, and occlusion of the branches were determined. Diameter growth of the branches continued for a longer time in older trees. Branch growth was also prolonged by rapid radial growth of the stem. On average, branches died 7 years after their growth cessation. The number of years that branches stayed alive after growth cessation was independent of the tree or stand characteristics. After the death of a branch, more than 40 years elapsed before the branch was occluded. Large branch diameter and rapid radial growth of the stem increased the width of the loose knot zone in the stem. The results showed that there are limited possibilities of using delayed thinnings to reduce the knottiness of timber, and artificial pruning is needed to produce timber of high quality.


2021 ◽  
Author(s):  
Kārlis Dūmiņš ◽  
Sigita Timma ◽  
Dagnija Lazdiņa

<p><strong>Key words</strong>: forest regeneration, Conniflex, Trico, mechanical site preparation</p><p>Forest regeneration is crucial stage in commercial forest management because actions during this stage impact future forest productivity and value. Scots pine is one of the main tree species in forestry of the northern part of Europe. Foresters have to overcome different risk factors during regeneration process and two of them are seedling damage by Pine weevil (<em>Hylobius abietis</em> L) and browsing by herbivores of <em>Cervidae</em> family. Pine weevil is one of the main forest pests in Europe that damage regenerated coniferous stands. Damage caused by this pest can produce 70% mortality of planted seedlings. Another significant risk factor is browsing. With increase of deer <em>(Cervidae)</em> population the damaged forest area also increases to the extent that foresters choose other tree species for regeneration. The mitigation of these risks is possible with appliance of forest management practices.  There are used different repelents against Cervidae animals.  Regarding Pine weevil, due to restrictions on insecticide use in EU, different protective coating materials have been developed, and several studies show that soil preparation before planting reduce amount of damaged Pine seedlings and increase possibility of successful regeneration.  We evaluated if and how forest management methods - soil preparation techniques (spot mounding, disc trenching) in combination with different plant protection products (Conniflex, Trico) - affects the degree of damage caused by pine weevil and <em>Cervidae</em> animals to Scots pine seedlings one and two years after outplanting in four forest stands in Latvia. The results from this study shows that application of Conniflex reduce number of damaged trees by 16.8% first and 20.3% second year after outplanting compared to untreated seedlings. Soil preparation has significant impact on reduction of pine weevil damage. The best results have been achieved by planting with Conniflex treated seedlings on spot mounds (2.4% damaged trees compared to 48.9% in unprepared soil without treatment). Repellent Trico do not provide additional protection against Pine weevil and do not have long term protection effect against browsing. Overall conclusion is that combination of soil preparation and use of appropriate coating material (Conniflex) can provide sufficient protection without usage of insecticides, and Trico has to be applied before winter season to achieve effect of protection.</p>


2019 ◽  
Vol 65 (No. 12) ◽  
pp. 461-471
Author(s):  
Viktoriia Lovynska ◽  
Petro Lakyda ◽  
Svitlana Sytnyk ◽  
Ivan Lakyda ◽  
Yuriy Gritzan ◽  
...  

Abstract: The research paper presents the results of the assessment of the annual stem production of Scots pine (Pinus sylvestris L.) and black locust (Robinia pseudoacacia L.) stands within the Northern Steppe of Ukraine. The research team has developed two- and three-factor regression models for assessing the live biomass stocks for the fractions of the wood and bark of the stems of the Scots pine and black locust stands. The paper also presents the dependences of the live biomass of the components of the stems of the stands on their selected biometric parameters. The direct positive correlation between the fractions of the wood, bark, and stem in total with the factors of age, mean diameter, mean height and stand density for both the studied species has been identified. The results include the distribution of the total stem production of the Scots pine and black locust stands by the state forestry enterprises of the Dnipro region. The mean annual stem production of Scots pine is characterised by lower values (stem wood –2.91 t·ha<sup>–1</sup>·yr<sup>–1</sup>, stem bark –0.38 t·ha<sup>–1</sup>·yr<sup>–1</sup>) compared with the investigated species – black locust with the stem wood 4.94 t·ha<sup>–1</sup>·yr<sup>–1</sup> and stem bark 1.70 t·ha<sup>–1</sup>·yr<sup>–1</sup>.


2019 ◽  
Vol 12 (3) ◽  
pp. 133-166 ◽  
Author(s):  
Alexander Gradel ◽  
Gerelbaatar Sukhbaatar ◽  
Daniel Karthe ◽  
Hoduck Kang

The natural conditions, climate change and socio-economic challenges related to the transformation from a socialistic society towards a market-driven system make the implementation of sustainable land management practices in Mongolia especially complicated. Forests play an important role in land management. In addition to providing resources and ecosystem functions, Mongolian forests protect against land degradation.We conducted a literature review of the status of forest management in Mongolia and lessons learned, with special consideration to halting deforestation and degradation. We grouped our review into seven challenges relevant to developing regionally adapted forest management systems that both safeguard forest health and consider socio-economic needs. In our review, we found that current forest management in Mongolia is not always sustainable, and that some practices lack scientific grounding. An overwhelming number of sources noticed a decrease in forest area and quality during the last decades, although afforestation initiatives are reported to have increased. We found that they have had, with few exceptions, only limited success. During our review, however, we found a number of case studies that presented or proposed promising approaches to (re-)establishing and managing forests. These studies are further supported by a body of literature that examines how forest administration, and local participation can be modified to better support sustainable forestry. Based on our review, we conclude that it is necessary to integrate capacity development and forest research into holistic initiatives. A special focus should be given to the linkages between vegetation cover and the hydrological regime.


2003 ◽  
Vol 154 (8) ◽  
pp. 305-313 ◽  
Author(s):  
Roman Eyholzer ◽  
Martin Baumann ◽  
Rolf Manser

Faced with the challenging task of balancing forest interests and wildlife, the Swiss Forest Agency initiated the pilot programme«Game and Forest», which is committed to a philosophy of goal-oriented management practice and a redesign of forestry subsidizing. Within this programme the diverse goals of forestry and hunting have been amalgamated to a superimposed goal and set out in a corresponding contract. The Game-Forest-Management-Tool (GFMT) has been divised to simulate the effect of various strategies to deal with the complex problems of forest-wildlife. Optimal contract-fulfilling procedures can be simulated on a PC using this technical tool. The efficiency of the measures suggested by simulations that were carried out are being tested in a study area within the pilot programme, «Game and Forest». Half way through this trial, after two years, we can say that there has been no significant increase of non-browsed areas. In 2004, after the collection of data for the entire study area, we will be able to tell whether applying this computer simulated strategy truly leads to an augmentation of non-browsed area and a decrease in bark-peeled forests in the pilot area.


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