• Title/Summary/Keyword: habitat characteristic

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Structural Design and Construction of Mega Braced Frame System for Tall Buildings

  • Chung, Kwangryang;Yoo, Seounghoon
    • International Journal of High-Rise Buildings
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    • v.8 no.3
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    • pp.169-175
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    • 2019
  • Recently, two unique high rise buildings have been designed and constructed in Korea. The two buildings, which consist of mega braces and mega columns, are 70-story, 105-story high rise buildings. Through two external structural frame systems, it will be analyzed mechanical and structural characteristic mega column and mega brace system in this report. Particularly, the joint has been studied through the analytical method based on the load transfer mechanism at the point where a mega brace and mega column meets.

A Habitat Characteristic of Population of Khingan Fir(Abies Nephrolepis) in Seoraksan National Park Using Landscape Indices (경관지수를 활용한 설악산국립공원 아고산대 분비나무개체군의 서식지 특성)

  • Lee, Ho-young;Park, Hong-chul;Lee, Na-yeon;Lee, Ho
    • Korean Journal of Environment and Ecology
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    • v.34 no.2
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    • pp.170-178
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    • 2020
  • There are few landscape ecological analyses of Khingan fir (Abies nephrolepis) and other habitats of the sub-alpine zone in South Korea. In this study, we tried to quantitatively interpret and assess the habitat characteristics by analyzing 15 landscape indices according to the differences in tree layer coverage, in the Khingan fir habitat growing naturally in the sub-alpine zone of Seoraksan National Park. It was difficult to identify the tendency of landscape ecology to increase and decrease the tree layer coverage in the study site, which was the entire Khingan fir habitat in Seoraksan National Park. However, the Khingan fir habitat was found to be generally low in coverage, and population density as the tree layer coverage of less than 50 percent accounts for 85 percent of the total habitat. Moreover, the Khingan fir habitat in the 10 to 50 percent range was fragmented into a total of 286 patches, making it relatively less connected to the habitat. The total edge length and edge density, which could determine the edge effect of the main part according to the physical form, were the highest in the habitat of 26 to 50 percent coverage, indicating a relatively high impact from outside than habitats of other coverages. The shape with the tree layer coverage of between 10 and 50 percent was more complex even with patches of the same size, and it is believed that these characteristics make it more susceptible to habitat fragmentation and external confounding. We expect that the results of this study can be useful for time series analysis of spatial expansion or reduction of the Khingan fir habitat in Seoraksan National Park and provide the reference data for the morphological change and movement of patches and the connectivity and break-off between forests.

Particle Image Velocimetry Measurement of Unsteady Turbulent Flow around Regularly Arranged High-Rise Building Models

  • Sato, T.;Hagishima, A.;Ikegaya, N.;Tanimoto, J.
    • International Journal of High-Rise Buildings
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    • v.2 no.2
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    • pp.105-113
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    • 2013
  • Recent studies proved turbulent flow properties in high-rise building models differ from those in low-rise building models by comparing turbulent statistics. Although it is important to understand the flow characteristics within and above high-rise building models in the study of urban environment, it is still unknown and under investigation. For this reason, we performed wind tunnel experiment using Particle Image Velocimetry (PIV) to investigate and identify the turbulent flow properties and characteristic flow patterns in high-rise building models. In particular, we focus on instantaneous flow field near the canopy and extracted flow field when homogeneous flow field were observed. As a result, six characteristic flow patterns were identified and the relationship between these flow patterns and turbulent organized structure were shown.

A Study on Vascular Plants, Distribution Status and Management Plans of the Cactus Habitat (No. 429 Natural Monument) in Wolryung-ri, Jeju Island (제주 월령리 선인장군락지(천연기념물 제429호)의 관속식물상, 분포실태, 관리방안에 관한 연구)

  • Lee, Cheol-Ho;Jang, Gye-Hyun;Ryu, Tae-Bok;Choi, Byoung-Ki
    • Journal of the Korean Institute of Traditional Landscape Architecture
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    • v.36 no.1
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    • pp.55-66
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    • 2018
  • The cactus habitat in Jeju Island has a phytogeographically specific distribution in the East Asian region, and forms a unique landscape as the only native cactus (Opuntia ficus-indica (L.) Mill.) habitat in Korea. However, there has been no detailed investigation on the distribution of cacti in the habitat and no investigation on the diversity of the mixed composition of plants in the habitats and their correlation with the distribution of cactus populations. This study attempted to investigate the diversity of vascular plants in the Wollyeong-ri cactus habitat and record the actual distribution and trends of cactus distribution. In addition to the distribution characteristics of cacti, we also discuss the characteristics of species reflecting the characteristics of the habitat among the mixed population of plant species, as well as the biological and environmental factors that threaten the maintenance of cactus populations or require management for preservation of cacti. Considering the phenological character, we conducted the field surveys for flora identification six times between June 2015 and September 2017. The Engler classification system was used for the arrangement sequence and names of plants, and the Korean Plant Names Index was adopted for the Korean name of the species. The study results showed that the Wolryung-ri cactus habitat in Jeju Island has the characteristic physiognomy of an area dominated by cactus. For the vascular plants, a total of 125 taxa were identified, including 53 families, 104 genera, 109 species, 15 varieties and 1 forma. Endangered plants specified by the Ministry of Environment were not found. Two species, Cyrtomium falcatum and Asplenium incisum, were identified as the ferns, and no gymnosperms were found. In addition, 123 taxa of angiosperms, 91 taxa of dicotyledones and 32 taxa of monocotyledons were identified. The distributions of cacti were confirmed in 289 meshes corresponding to 59.3% of the total 487 meshes in the cactus protected area, which showed various coverage distributions ranging from 5% to 95%. Most of the meshes where no cacti were found are coastal areas with exposed basalt rocks where the soil depth has not developed or extremely restricted due to repeated waves, or areas where artificial facilities, grasslands, and observation paths have been constructed. On the other hand, there were 71 lattice points in 14.5% of the total area where the cactus showed 70% or higher dominance. Cacti are randomly distributed in these areas. They have adapted to the microhabitat environment and are found to be opportunistically distributed along the growable locations. Considering that the reproduction of cacti in the habitat is mostly dependent on parthenogenesis, the present distribution seems to reflect the potentially distributable regions of cacti in the habitat. Based on the results of field surveys, a management plan for conservation and protection of the protected areas has been proposed.

A Characteristic on Community Structure of Benthic Macroinvertebrates of the Shinbulsan Wetland (신불산 고산습지의 저서성 대형무척추동물 군집구조의 특성)

  • Lee, Dong-Han;Hwang, Jong-Woo;Sung, Sung-Hoon;Yoon, Chun-Sik;Cheong, Seon-Woo
    • Journal of Environmental Science International
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    • v.18 no.5
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    • pp.561-567
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    • 2009
  • The distribution of benthic macroinvertebrates of Shinbulsan wetland was investigated. This study was focused on the degree of recovery of habitat by comparing the community structure of benthic macro invertebrates of zone D to that of zone A, intact habitat. The zone D was destructed due to the construction of a golf club and the survey was performed in zone A and zone D of Shinbulsan wetland. The seasonal survey was performed in April, July and September from 2006 to 2007. From the sampling, 2 phyla, 3 classes, 9 orders, 31 families, 69 species and 1155 individuals of benthic macroinvertebrates were collected. From zone A, 2 phyla, 3 classes, 9 orders, 23 families, 54 species and 678 individuals were identified. From zone D, 2 phyla, 3 classes, 9 orders, 23 families, 43 species and 477 individuals were identified. Species diversity and species richness were higher in zone A than in zone D. The recovery of zone D was inefficient as humidity of soil was not enough to live macroinvertebrates. Also, an endangered species of macroinvertebrates, Nannophya pygmaea was found during this investigation.

Exploration of Mycobiota in Cypripedium japonicum, an Endangered Species

  • Cho, Gyeongjun;Gang, Geun-Hye;Jung, Hee-Young;Kwak, Youn-Sig
    • Mycobiology
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    • v.50 no.2
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    • pp.142-149
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    • 2022
  • Orchids live with mycorrhizal fungi in mutualism. This symbiotic relationship plays an essential role in the overall life cycle of orchids from germination, growth, settlement, and reproduction. Among the 1000 species of the orchid, the Korean lady's slipper, Cypripedium japonicum, is known as an endangered species. Currently, only five natural habitats of the Korean lady's slipper remain in South Korea, and the population of Korean lady's slipper in their natural habitat is not increasing. To prevent extinction, this study was designed to understand the fungal community interacting in the rhizosphere of the Korean lady's slipper living in the native and artificial habitats. In-depth analyses were performed to discover the vital mycorrhizal fungi contributing to habitat expansion and cultivation of the endangered orchid species. Our results suggested that Lycoperdon nigrescens contributed most to the increase in natural habitats and Russula violeipes as a characteristic of successful cultivation. And the fungi that helped L. nigrescens and R. violeipes to fit into the rhizosphere community in Korean lady's slipper native place were Paraboeremia selaginellae and Metarhizium anisopliae, respectively. The findings will contribute to restoring and maintaining the endangered orchid population in natural habitats.

The Distribution Characteristics of Fish Community by Habitat Type in the Nonsan Stream (논산천의 서식처 유형별 어류군집의 분포특성)

  • Lee, Hwang-Goo;Choi, Jun-Kil
    • Journal of Wetlands Research
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    • v.16 no.3
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    • pp.303-313
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    • 2014
  • The spatial distribution characteristic of fish community were investigated at the 10 habitat types in the Nonsan stream from August, 2008 to June, 2009. The collected species during the surveyed period were 26 species belong to 6 families. Korean endemic species were Sarcocheilichthys nigripinnis morii, Squalidus japonicus coreanus, Hemiculter eigenmanni, Pseudobagrus koreanus, and Odontobutis interrupta which showed 19.2% ratio of total species. Dominant species was Zacco platypus, and subdominant species was Tridentiger brevispinis. Dominant species according to habitat types were Micropterus salmoides(substrate type pool and rock type pool), Lepomis macrochirus(channel connected pool and channel unconnected pool/abandoned type pool), T. brevispinis(channel unconnected pool/overflow type and run) and Z. platypus(riffle, meander type pool, side channel, and dam type pool). As a results of community analysis in side channel, diversity index showed relatively high values, indicating that habitat types in the Nonsan stream have relatively stable community structure. Bray-curtis cluster analysis indicated that the meander type pool and riffle showed the most similar values(80.8%). Moreover, cluster and principal component analysis were classified as 2 groups(lotic and lentic habitats).

The Study on the Habitat Change of Nannophya pygmaea Ramber in the Abandoned Paddy Field Ulsan City and Its Management (울산시 산림휴경지의 꼬마잠자리 서식지 변화 및 관리방안 연구)

  • Kim, Dong-Eon
    • Korean Journal of Environment and Ecology
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    • v.25 no.6
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    • pp.867-877
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    • 2011
  • A study was conducted to find the habitat change and the insects and flora that live in the abandoned paddy field in Daun-dong Jung-gu, Ulsan, to provide basic information for the conservation and restoration of Nannophya pygmaea Ramber from June 2008 to July 2011. In case of the insects, 53 species in 32 families of 10 orders were identified, with Odonata, Hemiptera and Coleoptera being the three dominants (18.9% in total). For flora, 60 species in 30 families of 23 orders were identified, with Cyperaceae and Gramineae being the dominants(13.3% and 11.7%, respectively). The influx of woody plants in the surveyed area led to the rapid progress of succession and the carnification of the habitats for aquatic plants. Besides, the number of phytophagous insects and mountainous insects were increasing. Consequently, the habitat of Nannophya pygmaea Ramber has been relocated to the place, whose water depth remains unchanged at 2.5~9.5cm and water space is opened. Therefore, it is required to conduct long-term monitoring and appropriate management based on the ecological characteristic of the habitats to continuously conserve and maintain the habitats of Nannophya pygmaea Ramber.

Studied on Habitat and Nest Characteristic of the Breeding Goshawk [Northern Goshawk] Accipiter gentilis in South Korea (한국에서 번식하는 참매 Accipiter gentilis 의 영소지 및 둥지 특성에 관한 연구)

  • Yi, Jin-Hee;Lee, In-Kyoon;Baek, Choong Ryul;Cho, Sam-Rae
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.16 no.5
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    • pp.83-92
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    • 2013
  • The present study documented the characteristics of habitats and nests of Goshawk [Northern goshawk] Accipiter gentilis breeding in Gongju-si, Chungcheongnam-do and Haepyung, Kyungsangbuk-do, Eumsung-gun, Chungju-si, Chungcheongbuk-do from April 2007 to August 2011. Breeding habitat includes of mixes and deciduous trees and ravine forest, ranging from small to large areas and it used make a new nest and fix up the old nest at Goshawk. Goshawk make nests on Japanese larch Larix leptolepis, Japanese red pine Pinus densiflora and Pitch pine Pinus rigidae of $15.8{\pm}2.36m$ (range=7.4~18.7m) in height and $34.6{\pm}7.38cm$ (range=20.8~47.4cm) in diameter-at-breast height (DBH). It has $135.8{\pm}3.37cm$ in outer diameter of nest, $26.2{\pm}2.39cm$ in inner diameter, $7.1{\pm}1.41cm$ of depth, and $3.1{\pm}0.40Kg$ of weight. Breeding habitat (n=13) has 5~7 nests. It has 7 (53.8%) nest in fix up the old nest and 4 (30.8%)nests in make a new nest.

A Study on Body Condition by Habitat in Larvae Korea Salamander (서식지 특성에 따른 한국산 도롱뇽 유생의 body condition에 관한 연구)

  • Kim, Eun Ji;Chung, Hoon
    • Korean Journal of Environmental Biology
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    • v.32 no.1
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    • pp.68-74
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    • 2014
  • Scientific study has investigated the body condition differences by habitat characteristics in larvae Korea salamander (Hynobius leechii) from March to April in 2012. To examine the sensitivity of external environment (predation risk), we divided two groups according to habitat characteristic; 1) Permanent pond and 2) Temporary pond. Howere, each larva was measured by head width at the level of the eye (HWE), largest head width (LHW) and snout-vent length, and we calculated the ratio of the head size by dividing HWE/LHW. As a result, larvae were larger in permanent pond group, had a faster growth rate than in temporary pond group. When exposed to the predator, larvae in permanent pond were smaller HWE/LHW than larvae in permanent pond. Therefore, these results indicate larvae in temporary pond more sensitive to the external environment.