• Korean Journal of Environment and Ecology
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• v.33 no.4
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• pp.440-446
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• 2019

This study examined the growth and fruiting characteristics and the acorns biomass allometric equation of Quercus acuta to provide reference data related to the growth and seed supply during the restoration of evergreen forest in the warm temperate zone in Wando Island, Korea. For the growth survey, we selected and cut three sample trees having a mean diameter at breast height (DBH) to investigate the growth analysis through a stem analysis. We then developed the allometric equation (Y=aX+b) of DBH and tree height growth characteristic (Y) according to the average tree age (X) of sampled trees and estimated the DBH and tree height according to the age of Quercus acuta. For the fruiting survey, we selected and cut three sample trees with full fruit in August when, they are at the early mature fruiting stage, for the analysis. To develop the acorns/tree biomass allometric equation of Quercus acuta, we selected and cut ten sample trees of evenly divided diameters. The acorns biomass allometric equation ($Y=aX^b$) was derived by analyzing the biomass (Y) and the growth characteristics (X), such as the DBH, tree height, crown width, and crown height. The allometric equations of average tree age according to DBH and tree height were Y=0506X-2.064 ($R^2=0.999$) and Y=0.321X+0689 ($R^2=0.992$), respectively. The developed allometric equations estimated that the DBH were 3.0cm, 8.1cm, 13.1cm and 18.2cm while the tree heights were 3.9m, 7.1m, 10.3m, and 13.5m when the tree ages were 10, 20, 30, and 40 years, respectively. The analysis results of fruiting characteristics showed that the length, the diameter, the number of fruits, and the number of acorns per fruiting branch had the statistically significant difference and tended to decrease from the upper part to the lower part of crown downward. The total number of acorns was 1,312 acorns/tree in the upper part, 115 acorns/tree in the middle part, and 5 acorns/tree in the lower part of the crown. The allometric equation for the amount of acorns with DBH as an independent variable was $Y=0.003X^{4.260}$ with the coefficient of determination at 0.896. Although the coefficient of determination of the allometric equation using only DBH as the independent variable was lower than that using DBH and tree height ($D^2H$), it would be more practical to consider only DBH as the independent variable because of measurement errors.

• Journal of Korean Society of Forest Science
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• v.105 no.3
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• pp.294-302
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• 2016

This study was conducted to evaluate aboveground tree biomass and nutrient (C, N, P, K, Ca, and Mg) response of tree components by high (1,933 trees $ha^{-1}$) and low (1,200 tree $ha^{-1}$) stand densities in a 27-year-old Quercus glauca plantation. The study site was located in Goseong county, Gyeongsangnam-do, southern Korea. Total 12 trees (6 high and 6 low stand densities) were cut to develop allometric equations and to measure nutrient concentration of tree components. Stand density-specific allometric equations in the high and low stand densities were significant (P < 0.05) in tree components with diameter at breast height (DBH). Also, generalized allometric equations could be applied to estimate tree biomass regardless of the difference of stand density because of no significant effect on slope of stand density-specific allometric equations. Aboveground tree biomass estimated by the allometric equations was significantly higher in the high stand density (177 Mg $ha^{-1}$) than in the low stand density (114 Mg $ha^{-1}$). However, nutrient concentration of tree components was not significantly affected by the difference of stand density. Nutrient stocks in tree components were not significantly between the high stand density and the low stand density, except for the N and P stocks of stem wood. These results indicate that aboveground tree biomass could be significantly affected by stand density, but nutrient concentration among the tree components was not affected by the difference of stand density in a Quercus glauca plantation.

• Ecology and Resilient Infrastructure
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• v.4 no.3
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• pp.149-155
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• 2017

Willow plants are representative biomaterials used in river restoration and main target trees in stream managements. In order to understand the changes in the growth of Salix subfragilis and S. chaenomeloides with their stand ages, we investigated the density, height and basal area of stems and biomass at their different aged stands of the riparian zone of the sand-bed stream, the Nakdong River, Korea. We also developed allometric equations for estimating the biomass of these two species by establishing the relationship between diameter at breadth height and tree height with above-ground biomass. The stem density showed a sharp decrease for 3 years after germination for S. subfragilis and 6 years for S. chaenomeloides, resulting in strong self-thinning. The stem height of the two species increased to 7.5 m in 15 years for S. subfragilis, and to 14 m in 13 years for S. chaenomeloides. Aboveground biomass also increased rapidly at the early stage of growth. The biomass increased to 17 ton DM/ha in 13 years for S. subfragilis and to 1,110 ton DM / ha in 13 years for S. chaenomeloides. It is expected that the allometric equations of two Salix species derived from this study will be applied to the objectively estimating the biomass of willow plants for the management of floodplain trees in streams.

• Korean Journal of Agricultural and Forest Meteorology
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• v.16 no.1
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• pp.29-38
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• 2014

Allometric equations for leaf, branch, stem and total above ground biomass of Pinus koraeinsis trees were developed with diameter at breast height(DBH) of trees, which were growing in a pine plantation with the stand density of 410 tree $ha^{-1}$ and the average DBH of $29.1{\pm}5.2$ cm in Mt. Taewha, Gyeonggi. Damage by Acantholyda parki reduced leaf biomass compared to other studies, however, its contribution to total biomass was minimal among parts. Comprehensive analysis revealed that constant in allometric equation for total above ground biomass (logY=a + blogX) was affected by average DBH and stand density, however, constant b was not. At the stand level, biomass for leaf, brach, stem, total above ground biomass were 6.68 Mg $ha^{-1}$, 18.82 Mg $ha^{-1}$, 101.02 Mg $ha^{-1}$, 126.53 Mg $ha^{-1}$, respectively. We developed a Korean pine stand biomass regression, which explained about 98% of variation with DBH and stand density based on comprehensive analysis.

• Journal of Korean Society of Forest Science
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• v.111 no.4
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• pp.502-510
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• 2022

In the national greenhouse gas inventory, a settlements category has never been included owing to the lack of activity data. Therefore, this study was conducted to obtain basic data for estimating biomass carbon storage in settlements. Nondestructive stem analysis with a laser dendrometer was performed on four major street tree species (Metasequoia glyptostroboides, Prunus armeniaca, Ginkgo biloba, and Acer buergerianum) in Wonju city, South Korea. Allometric equations of the aboveground volume were developed using five models, and allometric equations of crown area were developed with diameter at breast height (DBH) as an independent variable. The best performing allometric equations were aD²+bD+c for M.glyptostroboides and G. biloba, aD+bD² for P. armeniaca, and a+bD² for A. buergerianum. Regarding the allometric equations of crown area with DBH as an independent variable, G. biloba and A. buergerianum exhibited low coefficients of determination (R²), i.e., < 0.364, whereas M. glyptostroboides and P. armeniaca exhibited satisfactory R² values, i.e., > 0.767, probably due to different street tree management practices. The allometricequations in this study will support the carbon inventory of settlements and urban tree monitoring in management practices.

• Journal of Korean Society of Forest Science
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• v.99 no.1
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• pp.62-67
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• 2010

This study was carried out to develop local allometric biomass regression equations and to estimate aboveground biomass of red pine (Pinus densiflora S. et Z.) stands among three regions (Hadong, Hamyang, Sancheong) from the western regions of Gyeongnam province. We selected three natural red pine stands with similar stand ages (about 40-year-old) from each region. The allometric regression equations were significant in all tree components (P<0.05) and the determination of coefficient ($R^2$) ranged 0.87 from 0.99. There was a significant difference (P<0.05) in the biomass of tree components among three regions. The biomass was 173.3 Mg/ha in Hadong, 131.0 Mg/ha in Sancheong, and 66.5 Mg/ha in Hamyang. The proportion of biomass was 70.4-77.1% in stemwood, 10.9-15.2% in branch, 8.9-10.4% in stembark, and 3.1-4.4% in needle. The results indicated that red pine stands in the western Gyeongnam regions showed the significant difference of aboveground biomass which was attributed to site quality and stand density.

• The Korean Journal of Ecology
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• v.19 no.4
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• pp.305-320
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• 1996

It is necessary to obtain information about the productivity of the human-influenced forest and to understand the consumption of biomass resources in secondary forest in order to examine the resource flux by human activity in rural landscape. Thus the aims of this study were to elucidate the biomass and their use of secondary Pinus densiflora forests and to discuss sustainable utilization of secondary forests in rural landscape system. This study was carried out in Yanghwa-ri, Kongjugun, Chungcheongnam-do, central Korea. The changes of growth rate and aboveground biomass of a pine forest for 2 years were analyzed to understand forest management regimes in rural pine forests. Through allometric equations deduced from 25 sample trees, biomass was estimated. The biomass increase of pine forest was approximately 16.36 t/ha/yr in the unexploited stand and 12.24 t/ha/yr in the exploited stand. These were nearly equal to those of natural pine forests in central Korea. This result proved that human-influenced pine forest in rural landscape as well as the natural one has high potentiality to provide forest products. Making graveyard in forest-land was the important disturbance and land-use which currently occurring in rural landscape in the study area. Finally, we presented some forest management for stutainable and positive uses of secondary forests as one of the local energy resources in terms of the holistic landscape-ecological view.

• Journal of Forest and Environmental Science
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• v.33 no.2
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• pp.79-90
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• 2017

Improving the urban environmental quality relies mainly on the increasing of urban forests capacity to store carbon dioxide. This study assesses the floristic diversity of urban institutional lands in Bukavu and their potential to reduce atmospheric $CO_2$. An exhaustive inventory over three sites ($Coll{\grave{e}}ge$ Alfajiri, $Cath{\acute{e}}drale$ Notre-Dame de la Paix and Institut $Sup{\acute{e}}rieur$ $P{\acute{e}}dagogique$) of Bukavu led to the identification of 1,113 trees of which the diameter at breast height (1.30 m) ranged from 4.9 to 161 cm. Results reveal a floristic diversity made up of 4 families of conifers with 4 species and 14 of broadleaves with 21 species. Average densities were of $54trees\;ha^{-1}$ and $5.21m^2\;ha^{-1}$ of basal area. Urban-based allometric equations used yielded up to 312.8 tons of carbon stored in trees aboveground biomass equivalent to 1,147.9 tons of $CO_2$ reduced from the atmosphere over the three sites. The rate of carbon storage reaches $15.1tons\;ha^{-1}$. Thus, trees of the three institutional sites in Bukavu play an important role in reducing atmospheric $CO_2$ and contribute, thereby, to mitigate global climate change effects. Given the current environmental challenge associated with high population growth rate in cities, the urban forest ecosystem in DRC requires to be extended and further investigation.

• Journal of Wetlands Research
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• v.16 no.2
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• pp.245-250
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• 2014

This study developed allometry equation and estimated the aboveground-biomass of Quercus glauca, a warm-temperature, evergreen broad-leaved tree, growing in Kotzawal wetland located on Jeju Island. The allometric equations between DBH(diameter at breast height) and dry weights of stems (Ws), branches (Wb), leaves (Wl) and aboveground biomass (Wab) of Q. glauca were as follows: logWs=2.4042logDBH-1.3045, logWb=2.6436logDBH-1.6232, logWl =1.5428logDBH-1.3692 and logWab=2.3324logDBH-0.9181. The allometric equations between $D^2H$ and Ws, Wb, Wl, and Wab of Q.glauca were as follows : logWs=$0.853logD^2H-1.4252$, logWb=$0.8453logD^2H-1.5834$, logWl=$0.5328logD^2H-1.4073$ and logWab=$0.8453logD^2H-1.0327$. The $R^2$ between DBH and Ws, Wb, Wl and Wab were 0.9873, 0.9711, 0.7979 and 0.993, respectively. The $R^2$ between $D^2H$ and Ws,Wb,Wl and Wab were 0.9841, 0.9174, 0.7537 and 0.9876, respectively. There was no significant difference between observed and calculated values of the allomatric equations from DBH and $D^2H$(p>0.05, Kolmogorov-Smirnov test). Thus, to estimate the aboveground biomass of Q. glauca, use of DBH and $D^2H$ as an independent variables in the allometric equation is recommended.

• Journal of Forest and Environmental Science
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• v.38 no.3
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• pp.184-194
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• 2022

Triplochiton scleroxylon K. Schum is the plant species most affected by logging activities in the East Region of Cameroon due to its market value. This logging has impacted the ecological niche of the fern plant for which limited research has been done. The aim of this study is to contribute towards improving knowledge of fern richness and biomass on T. scleroxylon within the Central African sub-region. Fern data collection was done on 20 felled/harvested T. scleroxylon where, in addition to fern inventory, fern biomass was collected by the destructive method. The diameter and height of T. scleroxylon measured were used as explanatory variables in allometric equations for fern biomass estimation. Fern inventory was characterized using diversity index. Eight fern species were recorded on T. scleroxylon (≈5 species/T. scleroxylon). The minimum diameter where fern could be found is 59.4 cm. The average fern biomass found was 23.62 kg/T. scleroxylon. Pearson correlation coefficient showed a positive correlation (r>0.55) between fern biomass and T. scleroxylon diameter. For allometric equation, the logarithmic model improved better the adjustment than the non-logarithmic model. However, the quality of the adjustment is improved more when only the diameter is considered as an explanatory variable. Fern biomass is estimated to 90.08 kg/ha^-1 with 76.02 kg/ha^-1 being lost due to T. scleroxylon exploitation in the study area. This study is a contribution towards increasing knowledge of fern diversity specific to T. scleroxylon, and also fern biomass contribution to climate change mitigation and the potential carbon loss due to T. scleroxylon exploitation.