Single Tree Stability Assessment in Beech High Forest and Factors that Could Induce Windbreak

Wind in Europe is the main disturbing factor and the greatest damaging agent of forest stands, causing three times the annual damage caused by fires each year. The amount of trees destroyed by wind annually in Europe is over 38 million cubic meters. Given the importance and extent of the phenomenon of wind crashes, this has been one of the main topics on which forestry scientists have focused over time, so much so that already in the mid-1990s of the last century there were more than 200 scientific papers on this topic. However, most of these studies focused on the prediction of possible wind damage, paying attention to the population level and not to a single tree; moreover, almost all of the studies were carried out on conifers. Studies concerning the single tree have been carried out above all in urban forestry, where the trees live in unfavorable contexts and are very distant from what could be their optimal living conditions found in forests. The aim of this research was to search for possible correlations between the tree conformation and the crashes caused by windy events. This was in order to assess the characteristics predisposing trees to crash, in such a way as to provide the forest engineer with useful information in choosing the trees to take priority in order to reduce the damage caused by windy events. In conjunction with the “Vaia windstorm”, which affected much of Northern Italy, another meteoric event also occurred which caused the crash of numerous individuals inside the beech forest located on the summit of Monte Amiata, in Tuscany. On this occasion, an attempt was made to investigate the possible existence of single-tree scale indicators relating to a greater susceptibility to crash, in beech forests of the same age treated to shelterwood system, under the same phytosanitary, edaphic and topographical conditions. The research methodology applied is the same as in other studies carried out on the subject, in such a way as to allow comparison between the results obtained. Various parameters were analyzed, in particular: maximum height, crown insertion height, castle height, height corresponding to the maximum crown width, crown volume and surface. The findings showed that the main variables that had a significant influence on wind crashes were: tree height, crown surface and volume. In particular, the standing trees were taller than those crashed and with a larger crown.

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Tree slenderness coefficient at Bali Botanic Garden

IOP Conference Series Earth and Environmental Science ◽

10.1088/1755-1315/918/1/012038 ◽

2021 ◽

Vol 918 (1) ◽

pp. 012038

Author(s):

S F Hanum ◽

I D P Darma ◽

M B Atmaja ◽

G A E Oktavia ◽

H Merriansyah ◽

...

Keyword(s):

Correlation Analysis ◽

Negative Correlation ◽

Structural Damage ◽

Tree Height ◽

Sampling Technique ◽

Botanic Garden ◽

Tree Stability ◽

Standing Trees ◽

Bischofia Javanica ◽

Tree Development

Abstract Standing trees has a higher risk regarding structural damage that can cause trees or parts of trees to fail. Meanwhile, Bali Botanic Garden is located in a highland area that periodically gets natural disasters such as heavy wind. However, the information on tree stability is little known. Therefore, tree stability at Bali Botanic Garden was assessed using tree slenderness coefficient (SC) as an indicator. Purposive sampling technique was adopted for locations which highly visited. A total of 624 trees with dbh>40 cm were examined as samples. Trees were classified based on their SC as high (>80), moderate (SC:70-80), low (SC<70). Data were analyzed using descriptive and correlation analysis. Tree slenderness coefficient at Bali Botanic Garden classified as low (609 specimens), medium (11 specimens), and high (4 specimens). Trees with the high category were three individuals of Bischofia javanica Blume (SC=82.76, 83.69, and 89.63) and a Syzygium polyanthum (Wight) Walp. (SC=116.13). Trees with high SC had a higher susceptibility to wind-induced damage. There was a negative correlation between SC and others tree parameters except for tree height (r=0.44). Hence appropriate silvicultural treatment like thinning is recommended to enhance better tree development and minimize tree risk.

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Transient cell stiffening triggered by magnetic nanoparticle exposure

Journal of Nanobiotechnology ◽

10.1186/s12951-021-00790-y ◽

2021 ◽

Vol 19 (1) ◽

Author(s):

Jose E. Perez ◽

Florian Fage ◽

David Pereira ◽

Ali Abou-Hassan ◽

Sophie Asnacios ◽

...

Keyword(s):

Mechanical Properties ◽

Magnetic Nanoparticles ◽

Magnetic Nanoparticle ◽

Early Time ◽

Population Level ◽

Short Time Scale ◽

Initial Contact ◽

Almost All ◽

The Impact ◽

Stiffening Effect

Abstract Background The interactions between nanoparticles and the biological environment have long been studied, with toxicological assays being the most common experimental route. In parallel, recent growing evidence has brought into light the important role that cell mechanics play in numerous cell biological processes. However, despite the prevalence of nanotechnology applications in biology, and in particular the increased use of magnetic nanoparticles for cell therapy and imaging, the impact of nanoparticles on the cells’ mechanical properties remains poorly understood. Results Here, we used a parallel plate rheometer to measure the impact of magnetic nanoparticles on the viscoelastic modulus G*(f) of individual cells. We show how the active uptake of nanoparticles translates into cell stiffening in a short time scale (< 30 min), at the single cell level. The cell stiffening effect is however less marked at the cell population level, when the cells are pre-labeled under a longer incubation time (2 h) with nanoparticles. 24 h later, the stiffening effect is no more present. Imaging of the nanoparticle uptake reveals almost immediate (within minutes) nanoparticle aggregation at the cell membrane, triggering early endocytosis, whereas nanoparticles are almost all confined in late or lysosomal endosomes after 2 h of uptake. Remarkably, this correlates well with the imaging of the actin cytoskeleton, with actin bundling being highly prevalent at early time points into the exposure to the nanoparticles, an effect that renormalizes after longer periods. Conclusions Overall, this work evidences that magnetic nanoparticle internalization, coupled to cytoskeleton remodeling, contributes to a change in the cell mechanical properties within minutes of their initial contact, leading to an increase in cell rigidity. This effect appears to be transient, reduced after hours and disappearing 24 h after the internalization has taken place.

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TRIPLOID APPLE VARIETIES OF SUMMER RIPENING SELECTION VNIISPK ON CLONAL ROOTSTOCK 54-118

Vestnik of the Russian agricultural science ◽

10.30850/vrsn/2021/6/34-36 ◽

1970 ◽

pp. 34-36

Author(s):

А. M. Galasheva ◽

Е. N. Sedov

Keyword(s):

Tree Height ◽

Projection Area ◽

Cross Sectional ◽

Crown Width ◽

Crown Volume ◽

The World ◽

Apple Cultivars ◽

Crown Projection Area ◽

Academy Of Sciences ◽

First Time

For the first time in the world and in Russia, Academician of the Russian Academy of Sciences, breeder Evgeny Nikolaevich Sedov created a series of triploid apple cultivars from intervalent crosses 2х × 4х. Triploid apple cultivars bear fruit more regularly, have higher self-fruitfulness and have fruits of high marketability. The article presents data on the study of triploid apple cultivars of the summer ripening period of the VNIISPK breeding - Augusta, Daryona, Maslovskoye, Osipovskoye, Zhilinskoye, Spasskoye and Yablochny Spas as well as the control Canadian cultivar Melba on a semi-dwarf clone rootstock 54-118. Maslovskoye, Zhilinskoye, Spasskoye and Yablochny Spas have immunity to scab. The orchard was planted in 2014, the garden planting scheme was 5 x 2 m. The indicators of the growth force (tree height, crown width and stem diameter) and the yield of trees were studied. At the age of six, the trees of triploid cultivars reached a height of 2.2 m (Maslovskoye) to 3.0 m (Yablochny Spas) on a semi-dwarf rootstock 54-118. The highest indicators of crown volume (3.3-5.3 m3), crown projection area (4.2-5.3 m2) and the cross-sectional area of the stem (46.5-52.8 cm2) were in Osipovskoye, Yablochny Spas, Zhilinskoye and Spasskoye. The highest yield in an average of three years was given by triploid scab-immune apple cultivars on a semi-dwarf rootstock 54-118: Maslovskoye, Zhilinskoye, Spasskoye and Yablochny Spas.

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Estimating plot-level tree height and volume of Eucalyptus grandis plantations using small-footprint, discrete return lidar data

Progress in Physical Geography Earth and Environment ◽

10.1177/0309133310365596 ◽

2010 ◽

Vol 34 (4) ◽

pp. 515-540 ◽

Cited By ~ 43

Author(s):

S.G. Tesfamichael ◽

J.A.N. van Aardt ◽

F. Ahmed

Keyword(s):

Eucalyptus Grandis ◽

Tree Height ◽

Mean Value ◽

Primary Objective ◽

Stand Age ◽

Lidar Data ◽

Maximum Height ◽

Density Level ◽

Local Maxima ◽

Small Footprint

This study explores the utility of small-footprint, discrete return lidar data in deriving important forest structural attributes with the primary objective of estimating plot-level mean tree height, dominant height, and volume of Eucalyptus grandis plantations. The secondary objectives of the study were related to investigating the effect of lidar point densities (1 point/m2, 3 points/m2, and 5 points/m2) on height and volume estimates. Tree tops were located by applying local maxima (LM) filtering to canopy height surfaces created at each density level, followed by buffering using circular polygons. Maximum and mean height values of the original lidar points falling within each tree polygon were used to generate lidar mean and dominant heights. Lidar mean value was superior to the maximum lidar value approach in estimating mean plot height (R2∼0.95; RMSE∼7%), while the maximum height approach resulted in superior estimates for dominant plot height (R2 ∼0.95; RMSE∼5%). These observations were similar across all lidar point density levels. Plot-level volume was calculated using approaches based on lidar-derived height variables and stems per hectare, as well as stand age. The level of association between estimated and observed volume was relatively high (R2=0.82—0.94) with non-significant differences among estimates at high lidar point densities and field observation. Nearly all estimates, however, exhibited negative biases and RMSE ranging in the order of 20—43%. Overall, the results of the study demonstrate the potential of lidar-based approaches for forest structural assessment in commercial plantations, even though further research is required on improving stems per hectare (SPHA) estimation.

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Single-tree Equations for Estimating Biomass of Trembling Aspen, Large Tooth Aspen and White Birch in Ontario

The Forestry Chronicle ◽

10.5558/tfc57169-4 ◽

1981 ◽

Vol 57 (4) ◽

pp. 169-173 ◽

Cited By ~ 12

Author(s):

I. S. Alemdag ◽

K. W. Horton

Keyword(s):

New York ◽

Tree Height ◽

Stem Bark ◽

Trembling Aspen ◽

White Birch ◽

Stem Wood ◽

Single Tree ◽

Breast Height ◽

Forest Regions ◽

Whole Tree

Ovendry mass of single trees of trembling aspen, largetooth aspen, and white birch in the Great Lakes — St. Lawrence and Boreal forest regions in Ontario was studied in relation to stem dimensions. Mass equations for tree components based on diameter at breast height outside bark and tree height were developed. Results were found more dependable for stem wood and the whole tree than for stem bark, live branches, and twigs plus leaves. Ovendry mass values were slightly higher than those reported for New York and northern Minnesota.

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Assessment of the Pulpwood Quality of Standing Trees Using near Infrared Spectroscopy

Journal of Near Infrared Spectroscopy ◽

10.1255/jnirs.178 ◽

1998 ◽

Vol 6 (A) ◽

pp. A117-A123 ◽

Cited By ~ 9

Author(s):

L. R. Schimleck ◽

A. J. Michell ◽

C. A. Raymond ◽

A. Muneri

Keyword(s):

Near Infrared ◽

Nir Spectroscopy ◽

Tree Height ◽

Tree Breeding ◽

Pulp Yield ◽

Calibration Model ◽

Standing Trees ◽

Sampling Height ◽

Individual Trees ◽

Whole Tree

In Australia, considerable effort has been directed at improving the pulp yield of plantation grown trees through tree breeding programs. However, an improvement in pulp yield relies on the assessment of large numbers of trees. Traditional methods of assessment are expensive, time consuming and destructive, inhibiting their use. Cores can be extracted non-destructively from standing trees using TRECOR, a handheld motor driven drill. The cores are milled, their near-infrared spectra obtained and pulp yield estimated using an appropriate calibration model. The height at which the core is taken is very important. It must represent the whole tree and sampling must be easy and practical. The longitudinal and radial (within-tree) variation of pulp yield for 15 Eucalyptus nitens trees was examined using near-infrared (NIR) spectroscopy. The trees were taken from three families (five trees per family) selected for giving high, medium and low pulp yields respectively. Three trees (one from each family) were examined in detail. Maps of within-tree variation of pulp yield were developed. Pulp yield was found to be highly variable within individual trees and between trees of the same family. The yield of samples from 10% of tree height (approximately 2.2 m) gave the best correlation with whole-tree yield. Samples from 5% of tree height (approximately 1.1 m) gave a slightly lower correlation but provided a more convenient sampling height. Ten Eucalyptus globulus and ten E. nitens trees growing on five sites in Australia were used to examine the longitudinal variation of pulp yield. Trees from sites in Tasmania, Western Australia and Victoria were sampled. The optimal sampling height for E. globulus was 1.1 m. No single sampling height could be recommended for E. nitens due to large site effects.

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Individual Tree Measurement in Tropical Environment using Terrestrial Laser Scanning

Jurnal Teknologi ◽

10.11113/jt.v73.4329 ◽

2015 ◽

Vol 73 (5) ◽

Cited By ~ 1

Author(s):

Muhammad Zulkarnain Abdul Rahman ◽

Zulkepli Majid ◽

Md Afif Abu Bakar ◽

Abd Wahid Rasib ◽

Wan Hazli Wan Kadir

Keyword(s):

Laser Scanning ◽

Mean Squared Error ◽

Tree Height ◽

Point Clouds ◽

Tree Crown ◽

Individual Tree ◽

Branch Diameter ◽

Reference Tree ◽

Crown Volume ◽

Tree Branch

Detailed forest inventory and mensuration of individual trees have drawn attention of research society mainly to support sustainable forest management. This study aims at estimating individual tree attributes from high density point cloud obtained by terrestrial laser scanner (TLS). The point clouds were obtained over single reference tree and group of trees in forest area. The reference tree is treated as benchmark since detailed measurements of branch diameter were made on selected branches with different sizes and locations. Diameter at breast height (DBH) was measured for trees in forest. Furthermore tree height, height to crown base, crown volume and tree branch volume were also estimated for each tree. Branch diameter is estimated directly from the point clouds based on semi-automatic approach of model fitting i.e. sphere, ellipse and cylinder. Tree branch volume is estimated based on the volume of the fitted models. Tree height and height to crown base are computed using histogram analysis of the point clouds elevation. Tree crown volume is estimated by fitting a convex-hull on the tree crown. The results show that the Root Mean Squared Error (RMSE) of the estimated tree branch diameter does not have a specific trend with branch sizes and number of points used for fitting process. This explains complicated distribution of point clouds over the branches. Overall cylinder model produces good results with most branch sizes and number of point clouds for fitting. The cylinder fitting approach shows significantly better estimation results compared to sphere and ellipse fitting models.

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Field and Computer Application of Mesavage and Girard Form Class Volume Tables

Southern Journal of Applied Forestry ◽

10.1093/sjaf/22.2.81 ◽

1998 ◽

Vol 22 (2) ◽

pp. 81-87 ◽

Cited By ~ 1

Author(s):

Robert C. Parker

Keyword(s):

Regression Model ◽

Iterative Procedure ◽

Computer Applications ◽

Tree Size ◽

Computer Application ◽

Form Class ◽

Single Tree ◽

Standing Trees ◽

Taper Equation ◽

Volume Functions

Abstract Mesavage and Girard form class volume tables for estimating board foot volume of standing trees remain the most widely used volume tables in the East and South even though newer, more versatile and sophisticated volume functions are available. The volume tables are being misused by foresters because the merchantability standards of the average, upper-log taper table used to derive the volume tables does not show that merchantable top diameters and form class applications require appropriate sampling and accurate measurement of form on selected trees. The original upper-log tapers, developed from averages of actual tree measurements and ocular estimates, were fitted to a regression model to smooth the inconsistencies of the table values. The resulting Mesavage and Girard "taper equation" is used to obtain upper stem diameters for trees of known Girard form class, dbh, and merchantable height. The taper equation shows that top-limit diameter increases with both tree size (dbh and height) and Girard form class, and any attempt to apply form class volume tables to a fixed-top diameter on inventory trees would produce erroneous cruise volumes. The derived taper equation can be used in an iterative procedure during computer applications to obtain single tree volumes as the sum of log segment volumes for segments of user-defined length. A hierarchy of suggested form class application options is presented along with suggestion sampling, measurement, and stratification procedures. South. J. Appl. For. 22(2):81-87.

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Harvester efficiency in trunk utilisation and log quality of early thinning pine trees

Forest Research Papers ◽

10.2478/frp-2019-0004 ◽

2019 ◽

Vol 80 (1) ◽

pp. 45-53

Author(s):

Piotr S. Mederski ◽

Konrad Werk ◽

Mariusz Bembenek ◽

Zbigniew Karaszewski ◽

Mariusz Brunka ◽

...

Keyword(s):

Management Practice ◽

Tree Height ◽

Maximum Height ◽

Tree Trunk ◽

Pine Trees ◽

Expected Length ◽

Set Up ◽

Total Tree ◽

Very High

Abstract Obtaining high harvester efficiency in young pine stands during early thinning is achallenging management practice. One of the difficulties lies in achieving the optimal use of the tree trunk for assortments and obtaining satisfactory timber quality. The objective of this research was to find out 1) how much of the tree trunk can be processed by a harvester to produce logs, and 2) the quality of the assortments in terms of log length accuracy and delimbing quality. The work was carried out in a 31-year-old pine stand in northern Poland with the Vimek 404 5T harvester with the Keto Forst Silver head for early thinning. Eighty sample plots were set up within the stand for detailed tree analysis after harvesting. The total length of the assortments from each tree was measured as well as the minimal top diameter (under bark). Additionally, the lengths of the bottom, middle and top logs were measured as well as the height of the knots after delimbing. On average, 70% of the total tree height was used for assortments and logs were processed up to a mean top diameter of 5.3 cm under bark. The length accuracy was very high: 90% of the logs had the expected length, more than 9% had a commercially acceptable length, while only 0.7% of the logs were too long. After delimbing, the knots were of a maximum height of 2 cm. Using the Vimek 404 5T harvester in the 31-year-old pine stand was an effective solution for trunk processing and obtaining quality assortments.

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Investigations on developing a key for identification of elite nutmeg tree

Journal of Plantation Crops ◽

10.19071/jpc.2016.v44.i3.3166 ◽

2017 ◽

Vol 44 (3) ◽

pp. 166

Author(s):

H.C. Vikram ◽

N. Mini Raj ◽

S. Krishnan

Keyword(s):

Fruit Set ◽

Tree Height ◽

Fruit Weight ◽

Kernel Weight ◽

Quantitative Characters ◽

Quantitative Characteristics ◽

Almost All ◽

G Ratio ◽

Key Characters ◽

The Ideal

Nutmeg (Myristica fragrans Houtt.) is unique among tree spices, as the donor of two distinct spices; nutmeg and mace. Yield is a complex phenomenon in nutmeg. Fruit yield per tree is the targeted quantitative parameter which is dependent on several other yield related components. Hence, an attempt was made towards identification of an elite nutmeg tree using desirable characteristics which are easily measurable and recognizable. Forty six morphotypes of nutmeg selected from core collections in the Chalakudy river basin in Kerala in the age group of 15 years formed the material for study. These samples of nutmeg represented almost all nutmeg growing tracts of Kerala. The accessions were evaluated based on 51 qualitative and 38 quantitative characteristics and grouped based on similarities. Thirteen key quantitative characters were selected based on their impact on yield as well as commercial importance.The qualitative clusters were ranked based on relative best performance of the perceived key characters. Database was generated for the key characters and from this database, plausible value of each character was predicted. Accordingly, an elite nutmeg tree may be characterized as having the ideal characteristics with approximate values viz. tree height (8 m), canopy spread (E-W: 7 m, N-S: 8 m), number of flowers (6 per 10 cm2), fruit set percentage (37), number of fruits m-2 (19), fruit weight (81 g), thickness of pericarp (14 mm), dry mace weight (2 g), dry nut weight (10 g), kernel weight (7 g), ratio of nut to mace (6.6) and number of fruits per tree (3342). It is a simple key involving characters which are measurable and recognizable at the farmer level.

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