• Journal of Plant Biology
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• v.9 no.1_2
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• pp.7-16
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• 1966

In order to determine the factors related to site quality, 13 areas of Larch growing in the Kwangung and its vicinity forest as sample plots, were examined. Sample plots included various site classes as well as age classes. Three were divided into two groups (major and minor trees). Average height of dominant trees was determined through messurement of 5 to 6 dominant tree in each sample plots. Average height of dominant 30 year-old trees was the basis for site index. A Standard Yield Table for the larch produced in Kwangnung forest was made by various data, which included age class 5, ranging from 10 to 45 years. The relationship of the height of the trees, the site conditions, and ground vegetation are investigated in this paper. The site indexes of 40 forest class age in 28-B and 28-G forest classes of the larch associations for ground vegetation had comparatively rarge differences due to the sampled areas. The relation of the direction of forest communities to the height and the diameter of the tree shwoed that its communiteis of northest and northwest parts appeared higher valueof the height and the diameter. The diameter and the height of trees were closely realted to each other. The samller the occupied area per tree and the smaller the average distance among trees, the more density was increased. The larger the density was the lower height of the trees. In the ground vegetation of the larch communities, there seems to be a definite correlation between the height of trees and the occupied area per tree or the average distance among the trees. The height of trees and site index of two larch communities were as follow: 28-B forest class site index 20.8, height 24.0m, 28-G forest class site index 18.4, height 20.9m. The ground layer was analyzed by the method of Quadrat(20/20sq. cm) with an interval of 1M. It set up 40 Quadrats of the larch communiteis. The community structure of the ground vegetation of two larch was analyzed, and important value was calculated and then evaluated. The ground vegetation under the larch had developed Burmannii Beauv stratal society below the 28-B and 28-G the forest class. Accordingly, the first important value of Burmannii Beauv was found in two ground vegetation below the larch. Therefore, this species could be quantitatively considered as the forest indicator species. Common species of each community appeared 18 species out of 34 species in the ground vegetation under two larch communities. The ground vegetation of the 28-B forest class showed more than that of the 28-G forest class. the similarity of the ground vegetation was measrued by the Frequency Index Community Coefficient. The differences between the associations were lcearly manifested by the ground vegetation tested by Gleason's Frequency Index of Community Coefficient for the analysis of each stratal society of all associations. According to F.I.C.C. the ground vegetation under two larch(28-B and 28-G) forest classes showed higher value. An investigation into the relationship of physical and chemical properties of soil and site was considered the next step to be taken in the study of the larch site classification.

• Korean Journal of Plant Resources
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• v.30 no.4
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• pp.435-449
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• 2017

A floristic study on the vascular plants from Mt. Seounsan region, which ranges from Seoun-myeon, Anseong-si, Gyeonggi-do to Baekgok-myeon, Jincheon-gun, Chungcheongbuk-do, was conducted 9 times in total, from April 2014 to October 2015. Based on the voucher specimens, it was revealed that the vascular plants in this region comprised 501 taxa: 97 families, 306 genera, 439 species, 5 subspecies, 51 varieties, and 6 forma. Among these plants, 185 taxa were recorded for the first time from this region. 8 Korean endemic species including Asarum patens (K.Yamaki) B.U.Oh, Scutellaria insignis Nakai, and Weigela subsessilis (Nakai) L.H.Bailey were found in this region. 5 taxa of rare plants designated by the Korea Forest Service, including Iris ruthenica KerGawl., Leontopodium leontopodioides (Willd.) Beauverd, and Tricyrtis macropoda Miq., were also found. 11 taxa of floristic regional indicator plants in the $3^{rd}$ to the $5^{th}$ degrees were identified. In addition, 46 taxa of naturalized plants were recorded, and 2 taxa of ecosystem disturbance plants, which were Ambrosia trifida L. and Aster pilosus Willd., also found.

• The Korean Journal of Ecology
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• v.28 no.6
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• pp.389-393
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• 2005

This study was carried out to investigate the effects of soil acidification on the growth of 3-year-old Pinus densiflora seedlings grown for 21 weeks in brown forest soils acidified with $H_2SO_4$ solution. The concentrations of Al in the acidified soils were increased with increasing amount of $H^+$ added to the soil. The total dry weight of the seedlings was reduced by the addition of the $H_2SO_4$ solution. In addition, there was a strong positive correlation (r=0.97, p<0.01) between the dry weight of the seedlings and the molar (Ca+Mg+K)/Al ratio of the soil. The seedlings with the molar (Ca+Mg+K)/Al ratio of 1.0 resulted from approximately 50% growth reduction compared with the control value. The results suggest that the molar (Ca+Mg+K)/Al ratio of the soil may be a useful indicator for assessing the critical load of acid deposition.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.35 no.4
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• pp.126-133
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• 2017

This study analyzed hydrological changes of stormwater runoff of Seolleung Jeongneung zone according to the application of LID system based on landscape Architectural technology. The results are as follows. First, when flooding occurred in Gwanghwamun in July 27, 2011, the maximum instantaneous rainfall amount was 183 mm/hr recorded at 10:00 on 27th for 10 minutes, and it was confirmed that rainfall intensity more than three times as high as the maximum rainfall of 57.5 mm/hr. Second, it is possible to control peak flow rate in the case of 1,500mm of soil thickness, so that it is possible to improve the vulnerability of flood damage in Seolleung and Jeongneung zone when applying the LID system. Third, in the berm height scenario, peak flow rate control was not controled in all depth level models, but the first stormwater runoff was delayed by 4 hours and 10 minutes compared to the soil thickness scenario. It was interpreted as a relatively important indicator the soil thickness for the initial stromwater runoff reduction and the berm height for the peak runoff. Through this, the systematic adaptation of landscape-friendly ecological factors within the cultural property protection zone could theoretically confirm the effects of flood disaster prevention.

• Journal of Korean Society of Forest Science
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• v.110 no.4
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• pp.516-529
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• 2021

Coniferous forests in the Baekdudaegan protected area are gradually losing their landscape diversity and uniqueness along with their ecological stability due to changes in vegetation composition and structures caused by various disturbance factors, such as climate change, vegetation succession, and human interference. This study provides basic data for establishing a comprehensive conservation plan for coniferous forests in the Baekdudaegan protected area. We classified the vegetation unit types using the Zurich-Montpellier School of Phytosociology and two-way indicator species analysis methods and analyzed the species diversity and structural characteristics based on the vegetation information of 755 stands collected in the natural resources change survey of the Baekdudaegan mountains (2016 to 2020) by the Korea Forest Service. Therefore, the vegetation of the coniferous forests of theBaekdudaegan protected area was classified into 15 types under the vegetation unit hierarchy of two community groups, four communities, seven sub-communities, and 14 variants. Furthermore, we compared the total coverage among vegetation types, importance values, constancy classes, life-forms, and diversity indices. Additionally, the average total coverage and number of species per 100 m² of all coniferous forests were 232% and 21 species, respectively, with the species diversity and dominance indices averaging 1.907 and 0.222, respectively.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.26 no.2
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• pp.82-95
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• 2021

We investigated the temporal and spatial distribution characteristics of chemical oxygen demand (COD) and total organic carbon (TOC) in all 13 locations of Masan Bay from February to November in 2015. The COD and TOC contents were high during the June-August period when the pollution load increased. In particular, the concentrations of COD and TOC were about twice as high in the surface water as in the bottom water. In spatial distribution, the COD and TOC concentrations at the inner bay were about twice as high as those of the outer bay in Masan Bay. As a result of estimating the oxidation efficiency of COD from the surface layer of Masan Bay in 2015 based on the theoretical oxygen demand (TOD), it was at the level of about 23%. Due to the low oxidation efficiency of COD, there is a risk that the organic matter in Masan Bay will be somewhat underestimated. Therefore, for quantitative analysis of organic matter, COD and TOC analyses need to be combined.

• Journal of Korean Society of Forest Science
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• v.108 no.2
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• pp.189-199
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• 2019

The forest management paradigm has recently shifted from focusing on commercial production to focusing on ecosystem management. Accordingly, a natural seedling regeneration method that has a naturally high affinity has attracted much attention in recent years. The aim of this study was to determine the relationship among various environmental factors, lower stratum vegetation, and seedling regeneration in Pinus densiflora forests. The survey site comprised 50 sectors divided using the line transect method, and the survey data were divided into those from wet habitat (19 sites) and dry habitat (31 sites), depending on the soil humidity, and were analyzed separately to show the close relationship between soil humidity and natural seedling regeneration. As a result, the dry habitat exhibited high seedling density (157,419 trees/ha), with the main species being Quercus serrata, Zanthoxylum piperitum, Smilax china, and Pueraria lobata, while wet habitat exhibited low seedling density (57,895 trees/ha), with the main species being Stephanandra incisa, Castanea crenata, Lespedeza maximowiczii, Lysimachia barystachys, Aralia elata, and Styrax japonicus. The height and root-collar diameter under wet conditions exhibited faster growth than those under dry conditions. Height growth by the root-collar diameter in dry habitat increased faster than that in wet habitat. It was also confirmed that seedling regeneration in wet habitat exhibited a rapid growth pattern 5 years after germination. These results suggest that the seedlings begin to grow more rapidly after a period of suppression by competition with surrounding plants. Considering an ecosystem or ecological management approach, specific practices, such as bush control and vine clearing in wet habitats, should be more intensively conducted, especially at the beginning of the management operations.

• Korean Journal of Plant Resources
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• v.32 no.4
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• pp.379-406
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• 2019

A floristic study on the vascular plants from Juwangsan National Park was conducted 13 times in total, from March to October 2017. Based on the voucher specimens and pictures, it was revealed that the vascular plants in this region comprised 758 taxa: 112 families, 399 genera, 672 species, 4 subspecies, 72 varieties, and 10 forma. Among these plants, 221 taxa were recorded for the first time from this region. The taxa in category II of endangered plants designated by the Korean Ministry of Environment were two taxa, including Eleutherococcus senticosus (Rupr. & Maxim.) Maxim. and Epilobium hirsutum L. The rare plants numbered 5 taxa designated by National Institute of Biological Resources were also found. 20 taxa of Korean endemic plants including Corydalis alata B.U.Oh & W.R.Lee, Iris odaesanensis Y.N.Lee, and Scrophularia cephalantha Nakai were investigated in this region. 40 taxa of floristic regional indicator plants in the 3rd to the 5th degrees were identified. Naturalized plants of 55 taxa were recorded, and 3 taxa of ecosystem disturbance plants, which were Ambrosia artemisiifolia L., Aster pilosus Willd., and Lactuca scariola L., also found.

• Korean Journal of Plant Resources
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• v.35 no.2
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• pp.289-316
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• 2022

This study was investigated to elucidate the distribution of vascular plants and their usefulness of Seondalsan Mountain (1,236 m) in Bonghwa-gun, Gyeongsangbuk-do. The surveys were carried out 20 times from April in 2014 to October in 2020. The vascular plants of Seondalsan Mountain was consisted a total of 638 taxa based on the voucher specimens; 96 families, 341 genera, 562 species, 18 subspecies, 53 varieties, 5 forms. 20 taxa of the Korean endemic plants were recorded and 1 taxa of Critically Endangered (CR), 3 taxa of Vulnerable (VU) and 9 taxa of Least Concern (LC), designated by Korean Forest Service as rare plants, were investigated in this region. Furthermore, V, IV and III degrees of floristic regional indicator plants, designated by the National Institute of Ecology, were included 1 taxa, 11 taxa and 28 taxa, respectively. Among them, edible, medicinal, fragrant, industrial, ornamental, ecological restoration, forage/compost plants were included 440 taxa, 505 taxa, 19 taxa, 234 taxa, 335 taxa, 214 taxa and 269 taxa respectively. In addition, 30 taxa of naturalized plants were observed.

• Journal of Korea Water Resources Association
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• v.54 no.spc1
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• pp.1037-1051
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• 2021

Biochemical oxygen demand (BOD) concentration, one of important water quality indicators, is treated as the measuring item for the ecological chapter in lakes and rivers. This investigation employed novel two-stage hybrid paradigm (i.e., wavelet-based gated recurrent unit, wavelet-based generalized regression neural networks, and wavelet-based random forests) to predict BOD concentration in the Dosan and Hwangji stations, South Korea. These models were assessed with the corresponding independent models (i.e., gated recurrent unit, generalized regression neural networks, and random forests). Diverse water quality and quantity indicators were implemented for developing independent and two-stage hybrid models based on several input combinations (i.e., Divisions 1-5). The addressed models were evaluated using three statistical indices including the root mean square error (RMSE), Nash-Sutcliffe efficiency (NSE), and correlation coefficient (CC). It can be found from results that the two-stage hybrid models cannot always enhance the predictive precision of independent models confidently. Results showed that the DWT-RF5 (RMSE = 0.108 mg/L) model provided more accurate prediction of BOD concentration compared to other optimal models in Dosan station, and the DWT-GRNN4 (RMSE = 0.132 mg/L) model was the best for predicting BOD concentration in Hwangji station, South Korea.