• Title/Summary/Keyword: Natural stand

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A Study on Stand Structure and Competition Status by Site Types in Natural Deciduous Forest of Pyungchang, Kangwon-do (강원도(江原道) 평창(平昌) 지역(地域) 천연(天然) 활엽수림(闊葉樹林)의 입지유형별(立地類型別) 임분구조(林分構造)와 경쟁관계(競爭關係)의 구명(究明))

  • Shin, Man Yong;Yim, Jong Su;Lee, Don Koo
    • Journal of Korean Society of Forest Science
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    • v.90 no.3
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    • pp.295-305
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    • 2001
  • This study was conducted to reveal stand structure and competition status by site types of natural deciduous forest in Pyungchang, Kangwon-do. The study site was divided by nine different types based on elevation(higher than 1,000m, 700~1,000m. lower than 700m) and topography(ridge, slope, valley). The objective of this study is to provide a basic information necessary for the environment-friendly management methods of natural deciduous forest on the basis of the stand structure and competition status by site types. It is confirmed that the range from 700m to 1,000m in elevation was the most suitable for stand growth. Species diversity and richness index also tended to be increased as elevation decreased. The ridge was the best in terms of stand growth by topography and followed by slope and valley in order. In addition, as expected, species with high importance value showed relatively low evenness index. The distance-independent competition index was selected as the best competition index model in seven site types of natural deciduous forest. On the other hand, the distance-dependent competition index was highly correlated with periodic annual increment of diameter in both ridge at higher than 1,000m and valley of 700m to 1,000m in elevation. It is proved, as a result, that the best competition index model is somewhat different by site types. From the analysis growth characteristics and competition status by site types, it is identified that the species with high importance value performed well in both growth and competition. The growth of Q. mongolica was excellent in the areas of higher elevation than 700m. Although K. pilus had relatively low importance value in higher elevation than 1,000m and ridge of 700m to 1,000m, the species had stronger competition status rather than other species. Also, U. davidiana and M. amurensis were good in competition status at lower elevation than 1,000m. It is necessary, therefore, that appropriate tending practice should be adopted based on the growth pattern and competition status of each species distributed by site types.

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Ecological Forest Management and Reforestation Problem -Comparison of Diameter Increment of Fraxinus rhynchophylla between Artificial, Natural and Coppice Forest- (생태적 숲관리와 조림 문제 -조림지, 천연림, 맹아림에서 물푸레나무 직경생장 비교-)

  • 김갑태
    • Korean Journal of Environment and Ecology
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    • v.17 no.2
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    • pp.105-111
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    • 2003
  • To develope reforestation methods for enviromentally sound and ecological forest management, Fraxinus rhynchophylla stand structure and radial growth of the trees were invstigated and compared by study sites. Plantation forest studied on Fraxinus rhynchophylla, was located at Jawoon-ni Nae-myeun, Hongcheon-gun and natural forest studied on Fraxinus rhynchophylla, was located at Jangjeon-ni Jinbu-myeun, Pyeungchang-gun. In 7,8 years after planting, differences of annual diameter increment among three stand origins were significant. The highest mean annual diameter increments of F. rhynchophylla, 4.60 mm/year was measured in sprouting trees, and followed by natural seedlings 4.59 mm/year. The lowest values, 4.18mm/year did in planting trees. Early radial growth of planting F. rhynchophylla was measured lower than that of sprouting or natural seedlings. These facts mean that planting F. rhynchophylla is not proper regeneration methods. Other regeneration methods of F. rhynchophylla forest, by sproutings, direct seeding and natural seeding, might be researched and recommended.

Construction of PANM Database (Protostome DB) for rapid annotation of NGS data in Mollusks

  • Kang, Se Won;Park, So Young;Patnaik, Bharat Bhusan;Hwang, Hee Ju;Kim, Changmu;Kim, Soonok;Lee, Jun Sang;Han, Yeon Soo;Lee, Yong Seok
    • The Korean Journal of Malacology
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    • v.31 no.3
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    • pp.243-247
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    • 2015
  • A stand-alone BLAST server is available that provides a convenient and amenable platform for the analysis of molluscan sequence information especially the EST sequences generated by traditional sequencing methods. However, it is found that the server has limitations in the annotation of molluscan sequences generated using next-generation sequencing (NGS) platforms due to inconsistencies in molluscan sequence available at NCBI. We constructed a web-based interface for a new stand-alone BLAST, called PANM-DB (Protostome DB) for the analysis of molluscan NGS data. The PANM-DB includes the amino acid sequences from the protostome groups-Arthropoda, Nematoda, and Mollusca downloaded from GenBank with the NCBI taxonomy Browser. The sequences were translated into multi-FASTA format and stored in the database by using the formatdb program at NCBI. PANM-DB contains 6% of NCBInr database sequences (as of 24-06-2015), and for an input of 10,000 RNA-seq sequences the processing speed was 15 times faster by using PANM-DB when compared with NCBInr DB. It was also noted that PANM-DB show two times more significant hits with diverse annotation profiles as compared with Mollusks DB. Hence, the construction of PANM-DB is a significant step in the annotation of molluscan sequence information obtained from NGS platforms. The PANM-DB is freely downloadable from the web-based interface (Malacological Society of Korea, http://malacol.or/kr/blast) as compressed file system and can run on any compatible operating system.

Effects of Different Chair Heights on Ground Reaction Force and Trunk Flexion during Sit-to-Stand in the Elderly

  • Lee, Na-Kyung;Lee, Myoung-Hee
    • The Journal of Korean Physical Therapy
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    • v.26 no.6
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    • pp.449-452
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    • 2014
  • Purpose: The purpose of this study was to analyze the coordination between trunk flexion and lower limb extension contributing to vertical propulsion during sit-to-stand (STS) at different chair heights in the elderly. Methods: Ten elderly subjects were asked to stand up at their natural speed from different chair heights : (1) $90^{\circ}$ knee flexion; (2) $100^{\circ}$ knee flexion; (3) $110^{\circ}$ knee flexion; and (4) $120^{\circ}$ knee flexion. A standard chair without a backrest or armrests was used in this study. To remove inertial effects of upper limb movements, subjects were asked to stand up from a chair with their arms crossed at the chest. Mean of results of three trials were used in the analysis at different knee flexion angles. Distances moved by the shoulder for compensatory trunk movement was recorded by motion analysis and vertical force was recorded under foot using force plates. Distances moved by the shoulder and vertical ground reaction force measurements were analyzed using repeated ANOVA. Results: Distances moved by the shoulder significantly decreased with higher chair (p<0.05). Vertical forces were not significant difference on chair heights (p>0.05), but results of pairwise comparisons for vertical force revealed significant difference between $90^{\circ}$ knee flexion and $120^{\circ}$ knee flexion (p<0.05). Conclusion: Trunk movement is probably used as a compensatory mechanism at low chair heights to increase lift-off from sitting by the elderly.

Structure and Tending Method for Naturally Regenerated Young Pinus Densiflora Sieb. et Zucc. Stands (천연경신(天然更新)에 의한 소나무 유령임분(幼齡林分)의 구조와 무육방법(撫育方法))

  • Bae, Sang Won
    • Journal of Korean Society of Forest Science
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    • v.83 no.1
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    • pp.50-62
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    • 1994
  • This study is performed to consider the fitness of natural regenerating method and tending methods used now by surveying the stand structure and regenerating states of the 9 natural regenerated Pinus densiflora stands in Kangwon province. As a special consideration, it deals with the tending methods on the seedlings of Pinus densiflora and broad-leaved tree(Quercus mongolica) under competition. By the consideration on the number of trees, growing capacity and stand structures of Pinus densiflora stands, it reveals that Pinus densiflora is in the inferior in numbers at the competition to the broad-leaved species, and it could not occupy the stands as the dominant species if the stands were not tended. It is estimated that natural regeneration of Pinus densiflora stands by the clearcutting or seed tree system could not achieved due to the abundance of ground vegetation. Short-term shelter-wood system or strip stand method may be proposed as a successful method of natural regeneration. As the visible tending method for seedlings, the method which apply the mixed forest in group of Pinus densflora and Quercus mongolica different by the growing capacity and distribution characteristics is better thaw the one which tend the Pinus densiflora only.

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Ecological Attributes by Forest Types in the Natural Forest of Mt. Odae

  • Choi, Yeong Hwa;Kim, Ji Hong;Chung, Sang Hoon
    • Journal of Forest and Environmental Science
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    • v.33 no.1
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    • pp.66-73
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    • 2017
  • This study was conducted to evaluate the ecological attributes of forest types which were classified by cluster analysis in the natural forest of Mt. Odae on the basis of the vegetation data (232 sampling points) from the point-quarter sampling methods. For the classified types, the species composition was expressed by importance value to describe the stand structure and the species diversity was quantified using the Shannon's diversity index. Recognized forest types were 1) Quercus mongolica-Pinus densiflora-Betula ermanii forest type, 2) Mixed mesophytic forest type, 3) Q. mongolica forest type, 4) B. ermanii forest type. Species diversity indices of total and overstory were highest in the Mixed mesophytic forest type (3.465 and 2.942), and lowest in the B. ermanii forest type (0.118 and 0.832). In addition to that, Q. mongolica-P. densiflora-B. ermanii forest type was calculated as 3.226 and 2.565, and Q. mongolica forest type was calculated as 2.776 and 1.218 in total and overstory, respectively. It was considered that after the P. densiflora and B. ermanii first invaded and site condition became good, Q. mongolica-P. densiflora-B. ermanii forest type was dominated by Q. mongolica. Mixed mesophytic forest type showed the most stable stand structure with various species distributed uniformly. Q. mongolica forest type would preserve the present stand status for a while, and the B. ermanii in B. ermanii forest type would be pressed by other species over time.

Physical and Mechanical Properties of Quercus glauca Thunberg according to Forest Stand Characteristics (임분 특성에 따른 종가시나무의 물리·역학적 특성)

  • Hong, Nam-Euy;Won, Kyung-Rok;Yoo, Byung-Oh;Jung, Su-Young;Kim, Byung-Ro;Byeon, Hee-Seop
    • Journal of the Korean Wood Science and Technology
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    • v.44 no.5
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    • pp.767-775
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    • 2016
  • Wood properties are affected by environmental factors such as soil, topography, rainfall, and climate change. The physical and mechanical properties of Quercus glauca were analyzed in order to investigate the relationship between wood properties and forest stand characteristics related to regions and forest origins. Physical and mechanical properties of wood were influenced by region. And no significant difference was observed between natural and artificial forests with respect to wood quality properties. Therefore, these findings are expected to be useful as fundamental data for silviculture practices of these species for wood quality.

A Comparison of Compensatory Muscle Activation of Gluteus Maximus and Gluteus Medius in Subjects With and Without Chronic Ankle Instability During Three Functional Postures (세 가지 기능적 자세에서 만성발목불안정성의 대상자와 정상인의 대둔근과 중둔근 보상적 근활성도 비교)

  • Oh, Hee-Joo;Kim, Mi-Sun;Choi, Jong-Duk
    • Physical Therapy Korea
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    • v.22 no.1
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    • pp.1-8
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    • 2015
  • The purpose of this study was to compare the change in electromyography (EMG) activity in the gluteus maximus (G-max) and the gluteus medius (G-med) in subjects with and without chronic ankle instability (CAI) during three functional postures. Twenty four females were recruited for this study. Subjects were assigned into two groups: with CAI ($n_1=12$) and without CAI ($n_2=12$). The assessment postures were rotational squat, one leg stand above a gradient and crossed leg-sway. Electromyographic activities of the G-max and the G-med were recorded using surface EMG and was normalized using the maximal voluntary isometric contraction elicited using a manual muscle testing. Independent t-test was used to determine the statistical differences between two groups during the three functional postures. The comparisons of the three posture between two groups were performed using a one-way repeated analysis of variance. A Bonferroni adjustment used for post hoc analysis. The activation of EMG on G-max performing the one leg stand above a gradient and crossed leg-sway in subjects with CAI is significantly higher than normal group (p<.05). The activation of EMG on the G-max during the rotational squat was significantly increased, compared to those of the one leg stand above a gradient and crossed leg-sway (p<.05). The activation of EMG on G-med performing three exercise at CAI is significantly higher than normal group (p<.05). The activation of EMG on the G-med during the crossed leg-sway was significantly increased, compared to the rotational squat (p<.05). This study provides valuable information for clinician who research CAI.