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Developing volume and taper equations for Styrax tonkinensis in LaosOunekham, Khamsene January 2009 (has links)
A volume equation for predicting individual tree volume, and a taper function for describing a stem profile were developed for a little known species, Styrax tonkinensis (Siam benzoin) in northern Laos. The species has high potential commercial value and can make an important contribution to the local economy. It can provide two different types of products, a non-wood product (benzoin resin) and timber. In Laos, the most important product is currently resin, and the use of timber for commercial purposes is rare. One reason is that information about the timber is not available. In Vietnam, on the other hand, the species is an import pulpwood species.
Data used in this study came from 73 trees. Trees were purposely selected to ensure coverage of a full range of tree sizes. Measurement was undertaken only on over-bark diameters due to some constraints, limitations and problems during the field data collection. However, due to the importance of under-bark volume for this species, a small available dataset was used to build a bark model as an interim guide to the errors associated with using over-bark models for estimating under-bark volumes. From this bark model, errors in estimating under-bark volumes of trees with diameters at breast height between 10cm and 17 cm were approximately 18%.
Nineteen individual volume models, and 7 individual taper functions were compared for bias and precision. Collective names for the volume equations tested include single-entry, double-entry, logarithmic, combined variables. Most volume models had similar bias but a few were clearly biased. The models with similar bias were further evaluated by four common statistics including bias, standard error of estimates, standard deviation of residuals and mean absolute deviation. The results showed that a five parameter model was ranked first, and was the most precise model. However, the magnitudes of difference in prediction errors between this model and other models, particularly the three parameter model were not significant. For practical purposes, the simpler model was preferred.
Seven taper functions tested here belong to three different groups including single taper equations, compatible taper equations and segmented taper equations. Evaluation of taper equations used the same residual analysis procedures and criteria as those applied with volume equations. Graphical residual analysis showed that most taper models had similar precision with their errors in diameter predictions being similar in range. However, some models showed obvious bias. The most highly ranked taper model was a compatible taper model of polynomial form. It was the least biased model. The second ranked model was a single, simple model. This latter model is relatively simple to apply, but it is not compatible with the volume model, yielding slightly different estimates of volume if it is integrated and rotated around the longitudinal axis of a tree. However, if the sole purpose is to describe tree taper, it is the best model to use.
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Degsnės maumedyno taksacinių parametrų ir būklės analizė / Analysis of taxonomy parameters and condition of the larch trees in Degsnė arboretumLazauskaitė, Odeta 01 June 2011 (has links)
Magistro darbe įvertinti Degsnės maumedyno kiekybiniai ir kokybiniai taksaciniai parametrai, maumedžių būklė ir jos priežastys.
Darbo objektas - Prienų miškų urėdijos, Balbieriškio girininkijos 29 kv. 1 skl., 1,79 ha plote augantis Degsnės maumedynas, įeinantis į Nemuno kilpų regionino parko teritoriją.
Tyrimo tikslas - Atlikti Nemuno kilpų regioninio parko teritorijoje augančio Degsnės maumedyno realių taksacinių parametrų (kiekybinių, kokybinių) įvertinimą ir sanitarinės būklės analizę.
Darbo metodai – instrumentinis dendrometrinių rodiklių nustatymas, vizualinis maumedžių būklės įvertinimas.
Darbo rezultatai – 2011 metais nustatyta, kad Degsnės maumedyno vid.aukštis yra 39,8 m, o vid. skersmuo – 64,6 cm. Maumedyne auga 2 aukštesni maumedžiai, už aukščiausiu Lietuvoje laikomą medį - jų aukštis siekia 46,5 m. 3 maumedžių skersmuo daugiau nei 1 m. Storiausio maumedžio skersmuo – 108 cm.
Medyno pakraštyje augantys medžiai yra vid. 2 m žemesni už medyno viduje augančius medžius (atitinkamai 38,4 m ir 40,4 m ), tačiau 10 cm storesni (atitinkamai 73,3 cm ir 62,6 cm), turi vid. 5 m ilgesnes lajas (atitinkamai 23,9 m ir 18,9 m) ir storesnes šakas.
Medyno tūris - 1198 m3/ha. Vid. vieno medžio tūris – 5,8 m3. Net 18 medžių tūris didesnis nei 10 m3. Po maumedžių danga susiformavo II ardas (7L3E+Ą), kurio tūris dar 93 m3/ha.
I Krafto klasės medžiai medyne sudaro 91,1%. L.tiesūs ir tiesūs medžiai maumedyne sudaro 86,2%.
Tyrimų metu nustatyta, jog maumedžiai buvo sodinti kas 2,6x2,6 m... [toliau žr. visą tekstą] / The Master work evaluated quantitative and qualitative taxonomy parameters of larch trees in Degsnė arboretum, condition of larch trees and the reasons for such condition.
Object of work - Degsnė arboretum of larch trees growing in Prienai Forestry enterprise, Balbieriškis Forest Stewardship 29 sq. 1 land parcel, 1,79 ha area, included in Nemunas Loops regional park territory.
Goal of research – To carry out the evaluation of taxonomy parameters (quantitative and qualitative) and analysis of sanitary condition of larch trees in Degsnė arboretum in Nemunas Loops regional park territory.
Methods of work – instrumental determination of dendrometric indicators, visual immolation of larch tree condition.
Work results – in 2011 it was found that the medium height of larch trees Degsnė arboretum 39,8 m, and the medium diameter is 64,6 cm. The larch trees arboretum has 2 high trees, higher than the tree which was considered to be the highest in Lithuania – their height is 46,5 m. Diameter of 3 exceeds 1 m. The diameter of the thickest larch tree is 108 cm.
The trees growing at the edge of the arboretum in average 2 m lower than the tress in the middle of the arboretum (38,4 m and 40,4 m accordingly), however, they are thicker by 10 cm (73,3 cm and 62,6 cm accordingly), and have on average 5 m longer canopies (23,9 m and 18,9 m accordingly) and thicker branches.
Volume of the trees is 1198 m3/ha. Average single tree volume is 5,8 m3. As many as 18 trees have the volume exceeding 10 m3... [to full text]
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Vidzgirio maumedyno dendrometrinių parametrų IR būklės įvertinimas / Analysis of taxonomy parameters and condition of the larch trees in Vidzgiris arboretumVyzaitė, Sigita 21 June 2013 (has links)
Magistro darbe įvertinti Vidzgirio maumedyno kiekybiniai ir kokybiniai dendrometriniai parametrai, maumedžių būklė ir jos priežastys.
Darbo objektas - Alytaus miškų urėdijos, Dzirmiškių girininkijos 33 kv. 48 skl., ir 44 skl., 3,1 ha plote augantis Vidzgirio maumedynas.
Darbo metodai – instrumentinis dendrometrinių rodiklių nustatymas, vizualinis maumedžių būklės įvertinimas.
Darbo rezultatai – 2012 metais nustatyta, kad Vidzgirio maumedyno vid. aukštis yra 34 m, o vid. skersmuo – 59 cm. Storiausio maumedžio skersmuo – 85 cm.
Medyno pakraštyje 48 skl., augantys medžiai yra vid. 2 m žemesni už medyno viduje augančius medžius (atitinkamai 32,6 m ir 34,6 m ), o 44 skl., pakraštyje augantys medžiai mažesni 1,4 m už viduje augančius medžius (atitinkamai 31,1 m ir 32,5 m) , tačiau 48 skl 6,8 cm storesni medžiai (atitinkamai 60,2 cm ir 53,4 cm), o 44 skl., 5,7 cm didesnis. Medynų pakraščiuose augančių medžių lajos yra vidutiniškai 3 m ilgesnės už viduje augančių medžių lajas. Medyno tūris - 1073 m³/ha. Vid. vieno medžio tūris – 3,9 m.
II Krafto klasės medžiai medyne sudaro 86,5%. L.tiesūs ir tiesūs medžiai maumedyne sudaro 64,8% ir medyne daugiausia medžių yta vidutiniškai storomis šakomis 40,1 %. Tyrimų metu nustatyta, jog maumedyne 1 ha auga 300 medžių. Medyne vyrauja geros sanitarinės būklės medžiai - jų čia yra 76,4% (324 vnt.). Blogos ir l.blogos medžiai maumedyne sudaro 5,3% (22 vnt.). Dažniausia medžių būklės blogėjimo priežastis – stelbimas (10 vnt), Medyno viduje augantys... [toliau žr. visą tekstą] / The Master work evaluated quantitative and qualitative taxonomy parameters of larch trees in Vidzgiris arboretum, condition of larch trees and the reasons for such condition.
Object of the work - Vidzgiris arboretum of larch trees growing in Alytus Forestry enterprise, Dzirmiškių Forest Stewardship 33 sq. 48 and 44 land parcel, 3,1 ha area.
Methods of the work – instrumental determination of dendrometric indicators, visual immolation of larch tree condition.
The results - in 2012, showed that larch Vidzgiris average height of 34 m and a diameter of average - 59 cm. Larch thickest diameter - 85 cm.
A stand on the outskirts of the plot 48 trees is 2 m below the stand inside the standing trees (respectively, 32.6 m and 34.6 m), with 44 plots on the outskirts of trees below 1.4 m for indoor growing trees (respectively, 31.1 m and 32.5 m), but the plot 48 6.8 cm thicker trees (respectively, 60.2 cm and 53.4 cm), and 44 plot 5.7 cm higher. Stands of tree crown edge is approximately 3 m longer than the inside of tree crowns. Growing stock volume - 1073 m³ / ha. Average single-tree volume - 3,9 m.
Kraft Class II trees stand up 86.5%. Very straight and straight larch trees of 64.8% and a maximum stand of trees with thick branches of the impeding an average 40.1%. The studies showed that 1 ha of larch trees growing 300. The stand dominated by good sanitary condition of the trees - here are the 76.4% (324 pcs.). Poor and very poor larch trees of 5.3% (22 pcs.). The most common cause of... [to full text]
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Using LiDAR on a Ground-based Robotic Platform to Map Tree Structural PropertiesLópez Camargo, Omar Andrés 07 1900 (has links)
More efficient and reliable High-Throughput Field Phenotyping (HTFP) approaches are essential for the development of plant breeding and carbon storage studies, as well as the improvement of yield estimation in the food production sector. The use of ground-based platforms in combination with other data sources such as UAVs and satellites addresses constraints related to payload capacity restrictions and reduced below-canopy data collection. This study describes an early approach to the deployment of agile robots for HTFP that aims to estimate height, diameter at breast height (DBH), and volume for forty-three unique trees corresponding to two different species (E. variegata and F. altissima) occupying an urban-park. The data acquisition system consists of an agile robot from Boston Dynamics and a navigation enhancer LiDAR module from the same company. In order to obtain a point cloud using this system, it is necessary to overcome two challenges: a reduced vertical FoV of the LiDAR and limited management of the LiDAR module. A multiway registration approach is implemented to reconstruct a low-density digital twin of the experiment site, which is later georeferenced using points surveyed with a GNSS system. Subsequently, the point cloud is manually segmented using CloudCompare software to obtain individual tree point clouds. Three different algorithms are implemented to obtain height, DBH, and tree volume estimates from the individual point clouds. The results are statistically analyzed by species in order to characterize sources of error. The height estimation method had a Median Percentage Error (MPE) of 1.4% for E. variegata and 1.2% for F. altissima. The DBH estimation had an MPE of 20.1% for E. variegata and 13% for F. altissima. The volume estimation model returned an R2 of 0.86 for E. variegata and 0.98 for F. altissima. Finally, all three feature estimations are mapped into a GEOJson file. These findings, combined with the numerous advantages of using agile robots as mobile platforms in HTFP, enable more efficient and reliable estimation of important parameters such as aboveground biomass and carbon storage sequestration, as well as delivery the potential for improvements in crop monitoring and yield estimation.
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Modelo alométrico para estimativa da biomassa e estoque de carbono na Mata Atlântica : método não destrutivo com base em técnica de escaladaMarinho, Ludmila de Souza Varejão 23 March 2016 (has links)
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Dissertação Ludmila Marinho - PDF.pdf: 724605 bytes, checksum: c95cd39ceabcc294dd3c22783b2ba10f (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Universidade Federal Fluminense. Instituto de Química. Programa de Pós-Graduação em Geociências-Geoquímica. Niterói, RJ / O presente trabalho buscou estimar a biomassa viva acima do solo (BVAS) em um fragmento florestal da Mata Atlântica localizado no sopé da Pedra de Itaocaia, município de Maricá/RJ. Para ajustar uma equação alométrica para a área de estudos, 7 indivíduos arbóreos representativos da região foram escalados e um galho de cada árvore foi retirado. Este procedimento possibilitou a obtenção de medidas dos volumes dos diferentes compartimentos arbóreos (tronco, galhos grossos, galhos finos e folhas) e das respectivas densidades básica (média=0,52 g/cm3) e fresca (média = 0,94 g/cm3), medidas estas utilizadas para calcular os fatores de forma dos galhos (FFG) e arbóreo (FFA). De maneira geral, as contribuições dos galhos finos e folhas decrescem com o aumento do diâmetro da base do galho, já a porcentagem de galhos grossos cresce e o valor do FFG diminui com o aumento do diâmetro da base do galho. A contribuição dos compartimentos galhos grossos, finos e folhas somam 33% da BVAS total arbórea na região. O FFA = 0,65 foi o fator que melhor estimou a BVAS
por meio da equação alométrica BVAS = FFA*Db*AB*H, onde Db é a densidade básica, AB é
a área basal e H é a altura da árvore. As estimativas de BVAS e estoque de carbono foram de
100 t/ha e 50,5 tC/ha, respectivamente, sugerindo que o fragmento florestal da Pedra de
Itaocaia está num estágio de regeneração intermediário e com período de abandono estimado em 40 anos / This study aimed to estimate aboveground biomass (AGB) in an Atlantic Forest
fragment located at the Stone Itaocaia, Marica, Rio de Janeiro. To fit an allometric equation
for the study area, seven trees were scaled and a branch of each tree was removed. This
procedure enabled to obtain measurements of the volumes of different compartments of trees
(trunk, branches and leaves) and their basic densities (mean = 0.52 g/cm3) and cool (mean =
0.94 g / cm3), measures used to calculate the form factors of the branches (FFG) and the tree
(FFA). In general, the contributions of branches and leaves decrease with increasing the
diameter of the base of the branch, percentage of thick branches grow and FFG value
decreases with increasing the diameter of the base of the branch. The contribution of
branches, and leaves add 33% of the total tree AGB in the region. The FFA = 0.65 was the
factor that best predicted the AGB by the allometric equation AGB = FFA * H * AB * Db,
where Db is the density, AB is the basal area and H is the height of the tree. Estimates of
carbon stock and AGB were 100 t / ha and 50.5 tC / ha, respectively, suggesting that the
fragment of Stone Itaocaia is an intermediate stage of regeneration and abandonment period
estimated at 40 years.
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