scholarly journals Production potential and ecological stability of mixed forest stands in uplands - VI. A beech/larch stand on a mesotrophic site of the Křtiny Training Forest Enterprise

2008 ◽  
Vol 53 (No. 4) ◽  
pp. 170-184 ◽  
Author(s):  
V. Hurt ◽  
P. Kantor
Keyword(s):  
Sea Level ◽  
Natural Regeneration ◽  
Mixed Forest ◽  
The Other ◽  
Forest Stands ◽  
Ecological Stability ◽  
Production Potential ◽  
Growing Stock ◽  
Volume Increment ◽  
High Production

The paper is the 6<sup>th</sup> report on the production potential and stability of mixed forest stands in uplands. A mixed beech/larch stand that was established by natural regeneration in 1934 to 1942 is assessed. The stand is situated at an altitude of 460 m above sea level. It has been left to its natural development since 1961. At that time, the stand was characterized as an individually mixed, diameter- and height-differentiated 25-year pole-stage stand. The proportion of larch and beech amounted to 40% and 17%, respectively. Hornbeam (25%), oak (11%) and to a lesser extent birch (5%) and spruce (3%) also occurred in the stand. In the course of 42 years, the proportion of larch in this stand without planned thinning measures decreased to 35%. On the other hand, the proportion of beech increased to 39%. During all 5-year inventories, the stand could be characterized as a stabilized one with high production potential. Its initial growing stock 63 m<sup>3</sup>/ha at an age of 25 years increased to 497 m<sup>3</sup>/ha at an age of 67 years in 2003. At present, current volume increment amounts to 9.8 to 12.5 m<sup>3</sup>/ha/year.

scholarly journals Production potential and ecological stability of mixed forest stands in uplands – V. A mixed spruce/beech stand on a nutrient-rich site of the Křtiny Training Forest Enterprise

2012 ◽  
Vol 49 (No. 11) ◽  
pp. 502-514 ◽  
Author(s):  
P. Kantor ◽  
V. Hurt
Keyword(s):  
Mixed Forest ◽  
Health Condition ◽  
Forest Stands ◽  
Ecological Stability ◽  
Production Potential ◽  
Dominant Position ◽  
Beech Stand ◽  
The Given ◽  
Young Growth

The study is already the 5<sup>th </sup>account on the production potential and stability of mixed forest stands in uplands. A spruce/beech stand established in the mid-30s of the 20<sup>th</sup>century is assessed. The stand is situated at an altitude of 470 m and since 1960, it is left to its spontaneous development. At that time, the stand was characterized as a silviculturally neglected dense spruce young growth to a small pole-stage stand with an admixture of beech (spruce 71%, beech 13%). In the course of 41 years, spruce proportion in the stand without intentional thinning measures decreased from 71 to 56% and, vice versa, beech proportion increased from 13 to 31%. Present dominant and co-dominant position of spruce in the stand, its health condition and development in recent years indicate that the ecosystem under evaluation is stabilized fulfilling all functions on the given site at an age of 65 years. The stand is permanently fully stocked and its initial standing volume of 109 m<sup>3</sup>/ha at an age of 24 years in 1960 increased to 560 m<sup>3</sup>/ha at an age of 65 years in 2001.

scholarly journals Production potential and stability of a broadleaved mixed oak/hornbeam forest stand situated on a eutrophic site, Ždánický les

2012 ◽  
Vol 60 (6) ◽  
pp. 135-144
Author(s):  
Václav Hurt
Keyword(s):  
Tree Species ◽  
Forest Stand ◽  
The Other ◽  
Production Potential ◽  
Wild Cherry ◽  
Cherry Tree ◽  
Sessile Oak ◽  
Growing Stock ◽  
Volume Increment ◽  
Wild Service Tree

The paper focuses on assessing the growth and production of a mixed oak/hornbeam forest stand established by combined regeneration in 1940 to 1942. The stand is situated at an altitude of 460 m. Since 1961, it is left to its natural development. The 25–year–old stand was characterized as an individually mixed, both diameter- and height-differentiated pole-stage stand. The proportion of tree species was as follows: sessile oak 77 %, hornbeam 19 %, birch 1 %, lime 1 %, black poplar 1 %, wild cherry tree, wild service tree, and field maple. During 41 years of measurements, the proportion of oak slightly decreased to 76 %, on the other hand, the proportion of hornbeam increased to 22%. The initial growing stock of the 25–year–old stand, 75 m3.ha−1, increased to 323 m3.ha−1 at an age of 66 years in 2008. At present, current volume increment ranged between 6.3 m3.ha−1.year−1 and 11.6 m3.ha−1.year−1 during years 1967 and 1998. Since the age of 61, the growth of the stand has decreased and then even ceased due to increased mortality of oak.

scholarly journals Conversion of a forest managed under systems involving coupes to a selection forest on an example of the Opuky research area

2019 ◽  
Vol 48 (No. 1) ◽  
pp. 1-7
Author(s):  
J. Souček Souček
Keyword(s):  
Natural Regeneration ◽  
Research Area ◽  
The Other ◽  
Diameter Distribution ◽  
Initial Condition ◽  
Initial Composition ◽  
Growing Stock ◽  
Long Period ◽  
Model Condition ◽  
Selection Forest

This paper evaluates the development of growing stock, number of trees and diameter distribution of the standing volume in the Opuky locality where conversion to a selection forest has been the aim of management over a long period of time. With respect to species composition, the stand is divided into two plots. The initial condition and development of both plots differed. The favourable initial composition of the stand has gradually deteriorated due to delay in natural regeneration and therefore recruitment of young trees over a long period. The total number of trees on both plots has been low for target diameter of 51 cm. On the other hand, the growing stock has exceeded the model condition. The proportion of broadleaved species in the stand gradually increases, reducing the possibility of conversion to a selection forest in future.  

Note on Selection of Coordinate Systems for Geodynamics

1975 ◽  
Vol 26 ◽  
pp. 395-407
Author(s):  
S. Henriksen
Keyword(s):  
Sea Level ◽  
The Other ◽  
Coordinate Systems ◽  
Mean Sea Level ◽  
The Earth ◽  
The One ◽  
Static Systems ◽  
Selection Of

The first question to be answered, in seeking coordinate systems for geodynamics, is: what is geodynamics? The answer is, of course, that geodynamics is that part of geophysics which is concerned with movements of the Earth, as opposed to geostatics which is the physics of the stationary Earth. But as far as we know, there is no stationary Earth – epur sic monere. So geodynamics is actually coextensive with geophysics, and coordinate systems suitable for the one should be suitable for the other. At the present time, there are not many coordinate systems, if any, that can be identified with a static Earth. Certainly the only coordinate of aeronomic (atmospheric) interest is the height, and this is usually either as geodynamic height or as pressure. In oceanology, the most important coordinate is depth, and this, like heights in the atmosphere, is expressed as metric depth from mean sea level, as geodynamic depth, or as pressure. Only for the earth do we find “static” systems in use, ana even here there is real question as to whether the systems are dynamic or static. So it would seem that our answer to the question, of what kind, of coordinate systems are we seeking, must be that we are looking for the same systems as are used in geophysics, and these systems are dynamic in nature already – that is, their definition involvestime.

Reparação óssea no implante dental

2020 ◽  
Vol 12 (45) ◽  
pp. 63-66
Author(s):  
Halim Nagem Filho ◽  
Reinaldo Francisco Maia ◽  
Reinaldo Missaka ◽  
Nasser Hussein Fares
Keyword(s):  
Gene Expression ◽  
Titanium Surface ◽  
Close Contact ◽  
The Other ◽  
Main Function ◽  
Indirect Interaction ◽  
M2 Macrophages ◽  
Activated Macrophages ◽  
M1 Macrophages ◽  
High Production

The osseointegration is the stable and functional union between the bone and a titanium surface. A new bone can be found on the surface of the implant about 1 week after its installation; the bone remodeling begins between 6 and 12 weeks and continues throughout life. After the implant insertion, depending on the energy of the surface, the plasma fluid immediately adheres, in close contact with the surface, promoting the adsorption of proteins and inducing the indirect interaction of the cells with the material. Macrophages are cells found in the tissues and originated from bone marrow monocytes. The M1 macrophages orchestrate the phagocytic phase in the inflammatory region and also produce inflammatory cytokines involved with the chronic inflammation and the cleaning of the wound and damaged tissues from bacteria. On the other hand, alternative-activated macrophages (M2) are activated by IL-10, the immune complex. Its main function consists on regulating negatively the inflammation through the secretion of the immunosuppressant IL-10. The M2 macrophages present involvement with the immunosuppression, besides having a low capacity for presenting antigens and high production of cytokines; these can be further divided into M2a, M2b, and M2c, based on the gene expression profile.

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 The other side of sea level change

2020 ◽  
Vol 1 (1) ◽  
Author(s):  
Matthias Prange ◽  
Thomas Wilke ◽  
Frank P. Wesselingh
Keyword(s):  
Sea Level ◽  
Sea Level Change ◽  
The Other ◽  
Level Change

scholarly journals Distribution of the timber quality attribute ‘knot surface’ in logs of Fagus sylvatica L. from pure and mixed forest stands

2021 ◽  
Author(s):  
Kirsten Höwler ◽  
Torsten Vor ◽  
Peter Schall ◽  
Peter Annighöfer ◽  
Dominik Seidel ◽  
...  
Keyword(s):  
Fagus Sylvatica ◽  
Mixed Forest ◽  
European Beech ◽  
Forest Stands ◽  
Species Identity ◽  
Mixed Stands ◽  
Mixed Forests ◽  
Climate Conditions ◽  
Timber Quality ◽  
Positive Effects

AbstractResearch on mixed forests has mostly focused on tree growth and productivity, or resistance and resilience in changing climate conditions, but only rarely on the effects of tree species mixing on timber quality. In particular, it is still unclear whether the numerous positive effects of mixed forests on productivity and stability come at the expense of timber quality. In this study, we used photographs of sawn boards from 90 European beech (Fagus sylvatica L.) trees of mixed and pure forest stands to analyze internal timber quality through the quality indicator knot surface that was quantitatively assessed using the software Datinf® Measure. We observed a decrease in knot surface with increasing distance from the pith as well as smaller values in the lower log sections. Regarding the influence of neighborhood species identity, we found only minor effects meaning that timber qualities in mixed stands of beech and Norway spruce (Picea abies (L.) H. Karst.) tended to be slightly worse compared to pure beech stands.

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