• Journal of Korean Society of Forest Science
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• v.99 no.5
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• pp.726-735
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• 2010

Publications with the data on allometric equation, biomass and productivity of major oak forests in Korea were reviewed. Different allometric equations of major oak species showed site- or speciesspecific dependences. The biomass of major oak forests varied with age, dominant species, and location. Aboveground tree biomass over the different oak species was expressed as a power equation of the stand age. The proportion of tree component (stem, branch and leaf) to total aboveground biomass differed among oak species, however, biomass ranked stem > branch > leaf in general. The leaf biomass allocation over the different oak species was expressed as a power equation of total aboveground biomass while there were no significant patterns of biomass allocation from stem and branch to the aboveground biomass. Tree root biomass continuously increased with the aboveground biomass for the major oak forests. The relationship between the root to shoot ratio and the aboveground tree biomass was expressed by a logarithmic equation for major oak forests in Korea. Thirteen sets of data were used for estimating the net primary production (NPP) and net ecosystem production (NEP) of oak forests. The mean NPP and NEP across different oak forests was 10.2 and 1.9 Mg C $ha^{-1}year^{-1}$. The results in biomass allocation, NPP and NEP generally make Korean oak forests an important carbon sinks.

• Journal of Korean Society of Forest Science
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• v.98 no.5
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• pp.576-583
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• 2009

Based on the stem analysis and biomass measurement of 36 trees and 1,576 branches in Pinus sylvestris var. mongolica (Mongolian pine) plantations of Northeast China, this study was conducted to develop estimation model equation for leaf biomass of a single tree and branch, to examine the vertical distribution of leaf biomass in the crown, and to evaluate the proportional ratios of biomass by tree parts, stem, branch, and leaf. The results indicated that DBH and crown length were quite appropriate to estimate leaf biomass. The biomass of single branch was highly correlated with branch collar diameter and relative height of branch in the crown, but not much with stand density, site quality, and tree height. Weibull distribution function would have been appropriate to express vertical distribution of leaf biomass. The shape parameters from 29 sample trees out of 36 were less than 3.6, indicating that vertical distribution of leaf biomass in the crown was displayed by bell-shaped curve, a little inclined toward positive side. Apparent correlationship was obtained between leaf biomass and branch biomass having resulted in linear function equation. The stem biomass occupied around 80% and branch and leaf made up about 20% of total biomass in a single tree. As the level of tree class was increased from class I to class V, the proportion of the stem biomass to total biomass was gradually increased, but that of branch and leaf became decreased.

• Journal of Ecology and Environment
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• v.37 no.4
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• pp.177-184
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• 2014

This study was conducted to develop allometric equations and to determine the stem density and biomass expansion factor (BEF) for the estimation of the aboveground and belowground biomass of Cryptomeria japonica in Jeju Island, Korea. A total of 18 trees were harvested from the 40-year-old C. japonica stands in Hannam experimental forest, Jeju Island. The mean biomass of the C. japonica was $50.4Mg\;ha^{-1}$ in stem wood, $23.1Mg\;ha^{-1}$ in root, $9.6Mg\;ha^{-1}$ in branch, $4.6Mg\;ha^{-1}$ in needle and $4.3Mg\;ha^{-1}$ in stem bark. The diameter at breast height (DBH) was selected as independent variable for the development of allometric equations. To evaluate the performance of these equations, coefficient of determination ($R^2$) and root mean square error (RMSE) were used and results of the evaluation showed that $R^2$ ranged from 71% (root biomass equation) to 96% (aboveground biomass equation) and the RMSE ranged from 0.10 (aboveground biomass equation) to 0.33 (root biomass equation). The mean stem density of C. japonica was $0.37g\;cm^{-3}$ and the mean aboveground BEF was $1.28g\;g^{-1}$. Furthermore, the ratio of the root biomass to aboveground biomass was 0.32.

• Korean Journal of Ecology and Environment
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• v.57 no.2
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• pp.111-122
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• 2024

Zooplankton biomass is essential for understanding the quantitative structure of lake food webs and for the functional assessment of biotic interactions. In this study, we aimed to propose a biomass (dry weight) estimation method using the body length of cyclopoid copepods. These copepods play an important role as omnivores in lake zooplankton communities and contribute significantly to biomass. We validated several previously proposed estimation equations against direct measurements and compared the suitability of prosomal length versus total length of copepods to suggest a more appropriate estimation equation. After comparing the regression analysis results of various candidate equations with the actual values measured on a microbalance-using the coefficient of variation, mean absolute error, and coefficient of determination-it was determined that the Total Length-DW exponential regression equation [W=0.7775×e^2.0183L; W (㎍), L (mm)] could be used to calculate biomass with higher accuracy. However, considering practical issues such as the morphological similarity between species and genera of copepods and the limitations of classifying copepodid stages, we derived a general regression equation for the pooled copepod community rather than a species-specific regression equation.

• Journal of agriculture & life science
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• v.45 no.4
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• pp.65-72
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• 2011

The objective of this research is to develop biomass allometric equation for Pinus densiflora in central region and Quercus variabilis. To develop the biomass allometric equation by species and tree component, data for Pinus densiflora in central region is collected to 30 plots (70 trees) and for Quercus variabilis is collected to 15 plots (32 trees). This study is used two independent values; (1) one based on diameter beast height, (2) the other, diameter beast height and height. And the equation forms were divided into exponential, logarithmic, and quadratic functions. The validation of biomass allometric equations were fitness index, standard error of estimate, and bias. From these methods, the most appropriate equations in estimating total tree biomass for each species are as follows: $W=aD^b$, $W=aD^bH^c$; fitness index were 0.937, 0.943 for Pinus densiflora in central region stands, and $W=a+bD+cD^2$, $W=aD^bH^c$; fitness index were 0.865, 0.874 for Quercus variabilis stands. in addition, the best performance of biomass allometric equation for Pinus densiflora in central region is $W=aD^b$, and Quercus variabilis is $W=a+bD+cD^2$. The results of this study could be useful to overcome the disadvantage of existing the biomass allometric equation and calculate reliable carbon stocks for Pinus densiflora in central region and Quercus variabilis in Korea.

• Journal of Korean Society of Forest Science
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• v.96 no.5
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• pp.602-608
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• 2007

Forest plantations become important strategy not merely for the financial aspect, but for carbon sequestration and ecosystem stability. Forest plantations increase the density of the forest biomass, which reduce the increase in atmospheric carbon dioxide. Biomass density is also a useful variable for comparing structural and functional attributes of forest ecosystems across a wide range of environmental conditions. In this study, carbon sequestration of teak (Tectona grandis Linn. f.) in the individual tree and plantation levels estimation was carried out Site-specific allometric equation for the estimation of teak tree biomass was developed based on the direct measurement of fifteen (15) harvested trees in the Oak-twin Township of the Bago Yoma Region, Myanmar. A regression equation of the diameter at breast height (DBH) and the aboveground biomass (carbon content) was constructed to estimate the carbon storage level of plantations, which averaged 79 ton/ha. The average carbon accumulation in the soil (up to 30 cm in depth) was estimated 38.89 ton/ha, The highest mean annual increment (MAI) of total carbon was found in the 6-yr-old teak plantation (12.10 ton/ha/yr) whereas the lowest MAI was in the 26-yr-old teak plantation (4.31 ton/ha/yr).

• Journal of Environmental Science International
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• v.6 no.3
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• pp.219-224
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• 1997

The cloging phenomenon in the fixed film reactor Is shown when biomass growth Is excessive for long operating time. In addition, effluent water Quality gets worse because of detachment of biomass. In this study, we conducted air-backwashing to sustain biomass In reactor to complement these defects. The results of experimental are showed In the following conclusion. The detachment rate was 19.5 - 38.0% when the organic loading rate was 0.40 - 1.32 kg COD/$m^3$/day, the k - backwashing Intensity was 2 L/min(6.7 $m^3$/$m^2$/hrl and the backwashing time was 15 - 19 seconds. And the detachment rate was 32.2 - 58.6 % when the organic loading rate was 1.37 - 2.27 kg COD/$m^2$/day, the backwashing time was 1 - 12 minutes. As orgnic loading rate and backwashing time ale Increased, detachment of fixed biomass Is Increased. The detachment equation with detachment rate(DR, %), backwashing time(BWT, min), fixed biomass concentration(FB. mg/L), and organic leading rate(OLR, kg COD/ms/day) through multiple linear regession was given by the following equation: DR : 17.964 $BWT^{0.1407} FB^{0.0597} OLR^{0.1946}$

• Korean Journal of Ecology and Environment
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• v.56 no.2
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• pp.161-171
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• 2023

The medium-large cladoceran species Simocephalus spp. predominantly occur in habitats with developed aquatic vegetation. Accordingly, due to Simocephalus' high contribution to zooplankton community biomass in the lake's littoral zone and wetland habitats, estimating their biomass is important to understand the matter cycling based on biological interactions within the aquatic food web. In this study, we reviewed the length-weight regression equations used previously to estimate Simocephalus biomass, directly measured S. serrulatus' body specification (length, width and area) and their biomass(dry weight) using instruments such as a microscopic digital camera and a microscale, and performed regression analysis between each other. When S. serrulatus biomass was estimated using the equation (Kawabata and Urabe, 1998) presented in 『Biomonitoring Survey and Assessment Manual』, Korea, errors between estimates and measures were relatively large compared to the S. serrulatus species-specific biomass estimate equation developed by Lemke and Benke (2003). In addition, both equations showed not only increasing trends in error (estimate-measure) with increasing S. serrulatus' body length, but also in error variance among similar-sized individuals. The results of regression analysis with dry weight by body specifications indicated that the most appropriate equation for estimating the biomass of S. serrulatus was derived from the width-dry weight exponential regression equation (R²=0.9555). The review and development study of such species-specific biomass estimation equations for zooplankton can be used as a tool to understand their role and function in aquatic ecosystem food webs.

• Journal of Forest and Environmental Science
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• v.34 no.2
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• pp.108-118
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• 2018

Biomass determination of species-specific in forest ecosystem by semi-destructive measures requires the development of allometric equations; predict aboveground biomass observable independent variables such as, Diameter at Breast Height, Height, and Volume are crucial role. There has not been equation of this type in mountain Chuqala natural forest. In this study two species namely, Hypericum revolutum Vahl. & Maesa lanceoleta Forssk. with tree diameter classes (15-20, 20.5-25, and 25.5-35 cm), with the purpose of conducting allometric equations were characterized. Each species assumed considered individually. For the linear model fit the two observed variable DBH, H and V were preferred for the prediction of above ground biomass. The best fitted model choose among the two formed model were identified using Akaike Information Criterion (AIC), and $R^2$ and adjacent $R^2$. Based on this the best fit model for Hypericum revolutum Vahl. was AGB=-681.015+4,494.06 (DBH), and for Maesa lanceoleta Forrsk. was. AGB=-936.96+5,268.92 (DBH).

• The Korean Journal of Mycology
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• v.37 no.1
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• pp.55-59
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• 2009

The mushroom takes in charge of decomposer in ecosystem and its production is important indicator for sounded ecosystem function. To determine standing crop of basidiocarps(fruit body of mushroom), a weight must be measured by harvesting mushroom individual in the field. But this method has profound affection on the basidiocarps population or its surrounding condition due to habitat destruction. Thus, in this study, without harvesting any mushroom in the field, we developed allometric equation using some morphological parameters to estimate standing crop biomass of basidiocarps. Lentinula edodes, Pleurotus ostreatus, Flammulina velutipes and Conocybe tenera were used for allometry. Morphological variables of the mushroom were pileus diameter, pileus area, stipe length and stipe thickness. Consequently, all the experimental mushrooms species showed significantly correlation in biomass estimation of basidiocarps from allometric equation (p<0.05). As a result of this research, the standing biomass of the basidiocarps could be indirectly estimated with proportional expression, allometric equation drived from morphological characters.