• Title/Summary/Keyword: national forest

Search Result 10,410, Processing Time 0.04 seconds

Studies on Visitors' Use Characteristics in Campus Forest of Chungnam National University (충남대학교 교내연습림 이용특성에 관한 연구)

  • Lee, In-Se;Kim, Se-Bin;Jeoung, Woon-Ha;Lee, Byeong-Yil
    • Korean Journal of Agricultural Science
    • /
    • v.25 no.1
    • /
    • pp.33-40
    • /
    • 1998
  • The purpose of this study is to suggest objective basic data for Kung-dong neighborhood park management through the quantitative analysis of user's behaviors and satisfaction in Chungnam National University campus forest. Most users lived in Kung-dong, Oun-dong, Shinsung-dong near the campus forest. Their visiting motivations were for taking a walk, health and fresh air. Therefore, it is important that the university should seek a supervision for improving functions of the campus forest. They are using about 300 users per day in campus forest. We should present a supervision programs which make them more useful and protective.

  • PDF

Reduction of CO2 Fertilization due to Progressive Nitrogen Limitation - Physiological Changes of Four Native Tree Species Growing under Elevated CO2 for 8 years using Open-Top Chamber (점진적 질소 제한으로 인한 이산화탄소 시비효과 감소 - 상부개방형 온실을 이용한 고농도의 이산화탄소 하에서의 우리나라 대표 수종들의 생리적 변화)

  • Song, Wookyung;Byeon, Siyeon;Lee, HoonTaek;Lee, Minsu;Lim, Hyemin;Kim, Hyun Seok
    • Proceedings of The Korean Society of Agricultural and Forest Meteorology Conference
    • /
    • 2018.06a
    • /
    • pp.77-78
    • /
    • 2018
  • PDF

The Ecological Characteristics of Classified Forest Cover Types in the Natural Forest of Sobaeksan

  • Lim, Seon-Mi;Kim, Ji Hong
    • Journal of Forest and Environmental Science
    • /
    • v.31 no.2
    • /
    • pp.126-135
    • /
    • 2015
  • This study was conducted to evaluate the ecological characteristics of forest cover types which were classified by cluster analysis in the natural forest of Sobaeksan on the basis of the vegetation data from the point-quarter sampling method. Recognized forest cover types were 1) Mixed mesophytic forest, 2) Taxus cuspidata forest, 3) Fraxinus rhynchophylla-Quercus mongolica forest, 4) Betula ermanii forest, 5) Pinus densiflora forest, 6) Quercus mongolica mixed forest, and 7) Quercus mongolica pure forest. For those of classified types, the species composition was expressed by importance value (IV) to describe the community floristically. The species diversity was quantified using the Shannon's diversity index. The results showed that the forest cover types were characteristically different from one another in growing species and compositional rates, depending upon the type which was formed by a number of similar vegetational sample points. Species diversity indices (H') of total and overstory both were the highest in the mixed mesophytic forest (3.530 and 2.880, respectively), and lowest in the Q. mongolica pure forest (2.122 and 0.000, respectively) with only one canopy species. The highest species diversity in the mixed mesophytic forest may due to the relatively high species richness and evenness in the forest cover types. The description on ecological characteristics were suggested to understand the formation and development of forest cover types in this study area.

Effect of Spray-drying Condition and Surfactant Addition on Morphological Characteristics of Spray-dried Nanocellulose

  • Park, Chan-Woo;Han, Song-Yi;Namgung, Hyun-Woo;Seo, Pureun-Narae;Lee, Seung-Hwan
    • Journal of Forest and Environmental Science
    • /
    • v.33 no.1
    • /
    • pp.33-38
    • /
    • 2017
  • In this study, spray-drying yield and morphological characterization of spray-dried cellulose nanofibril (CNF) and TEMPO-oxidized nanocellulose (TONC) depending on spray-drying condition and surfactant addition was investigated. As spray-drying temperature increased, the yield of spray-dried CNF was increased. The highest spray-drying yields in both nanocelluloses were found at didecyl dimethyl ammonium chloride (DDAC) addition of 2.5 phr at all investigated temperatures. The spray-dried CNF was the sphere-like particle, but the spray-dried TONC showed both rod and sphere-like morphology. The average diameter of spray-dried CNF was decreased with increasing DDAC addition amount, resulting in the increase of specific surface area.

Pyrolysis Properties of Lignins Extracted from Different Biorefinery Processes

  • Lee, Hyung Won;Jeong, Hanseob;Ju, Young-Min;Youe, Won-Jae;Lee, Jaejung;Lee, Soo Min
    • Journal of the Korean Wood Science and Technology
    • /
    • v.47 no.4
    • /
    • pp.486-497
    • /
    • 2019
  • The non-isothermal and isothermal pyrolysis properties of H lignin and P lignin extracted from different biorefinery processes (such as supercritical water hydrolysis and fast pyrolysis) were studied using thermogravimetry analysis (TGA) and pyrolyzer-gas chromatography/mass spectrometry (Py-GC/MS). The lignins were characterized by ultimate/proximate analysis, FT-IR and GPC. Based on the thermogravimetry (TG) and derivative thermogravimetry (DTG) curves, the thermal decomposition stages were obtained and the pyrolysis products were analyzed at each thermal decomposition stage of non-isothermal pyrolysis. The isothermal pyrolysis of lignins was also carried out at 400, 500, and $600^{\circ}C$ to investigate the pyrolysis product distribution at each temperature. In non-isothermal pyrolysis, P lignin recovered from a fast pyrolysis process started to decompose and produced pyrolysis products at a lower temperature than H lignin recovered from a supercritical water hydrolysis process. In isothermal pyrolysis, guaiacyl and syringyl type were the major pyrolysis products at every temperature, while the amounts of p-hydroxyphenyl type and aromatic hydrocarbons increased with the pyrolysis temperature.

Effect of Aroma Therapy on the Stress Alleviation and Job Satisfaction of Taxi Drivers

  • Seo, Yeongwan;Kim, Soyeon;Jeong, Sooncheol;Lee, Daesung;Choi, Jungkee
    • Journal of Forest and Environmental Science
    • /
    • v.36 no.4
    • /
    • pp.318-325
    • /
    • 2020
  • This study was carried out to find the effects of aromatherapy using natural fragrance on reducing stress and improving job satisfaction of transportation workers in the taxi industry. A total of 120 workers were divided into the experimental group and the control group according to the inhalation of the fragrance and tested for 2 weeks. After 2 weeks, the difference of emotional change, stress analysis, and evaluation of job satisfaction according to aromatherapy were compared between the two groups. The result showed that the experimental group had a higher interest in scent products than the control group and that they wanted to encounter a lot of real scents, indicating that aromatherapy caused positive interest in general scent likability. In addition, the experimental group said that the inhalation of fragrance would refresh the feeling of the passengers in the vehicle and smoothly communicate with the passengers. Especially, it showed a significant difference between the two groups in terms of tension relief, pleasure and good mood by inhalation of fragrance, indicating the positive effect on job satisfaction.