• Title/Summary/Keyword: forest environmental factors

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The Distribution of Dictyostelids Cellular Slime Molds in Gokneung and Anyang Streamside and Effects of Environmental Factors on Its Distribution (하천(곡릉천,안양천)변 토양에서 세포성 점균의 분포 및 토양 환경요인의 영향)

  • 권혜련;장남기
    • Asian Journal of Turfgrass Science
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    • v.10 no.3
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    • pp.195-211
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    • 1996
  • Dictyostelids cellular slime molds were isolated from the soils of Gokneung and Anyang streamside in Korea. The fifteen species including two undescrihed species were identified. These were as follows ; Dictyostelium macrocephalurn D. sphaerocephalum, D. aureum var. aureum, D.mucoroides, D. minutum, Polyspondyium pallidum. D. giganteum, P. violaceum. D. purpureum. D.brefeldianum, D. flavidum, D. mucoroides var. storoniferum, D. septentrionalis, D. aureum var. luteolum,D. aureo-stipes var. aureo-stipes. D. macrocephalum was the dominant species. and D. sphaerocephalum. D. aureum var. avreum were relatively common. D. mucoroides var. storoniferum, D. septentrionalis were the undescrihed species in Korea. In the soils of streamside, dominant species was shifted by D. macrosephalum, D. sphaerocephalum. which were rare in the forest soils. The total clones per gram of streamside soils were greater than that of forest soils, whereas the number of species in streamside was smaller than the in forest soils. As a result, the ratio of the number of clones to species was very high in the soils of streamside, Environmental factors of soil pH, water content, organic content, total nitrogen and total phosphorus made a effect differently on the cellular slime molds community. Key words: Cellular slime molds, D. macrocephalum, D. sphaerocephalum, Shift of dominant species, Environmental factors.

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Changes of Road Structures according to the Environmental Factors in Forest Road (임도의 환경요인에 따른 임도구조의 변화)

  • Cha, Du Song;Choi, Byoung Koo;Koo, Sung Dae;Oh, Jae Heun
    • Journal of Forest and Environmental Science
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    • v.20 no.1
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    • pp.93-109
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    • 2004
  • To provide the basic informations related to forest road construction of mountainous terrain, we analyzed changes of the road structure factors such as banking and cutting slope gradients, slope length, road width by the environmental factors such as locations, slope gradients, soil types, road position on physically stabilized forest roads constructed in Gangwon-do. All factors related to the road structures by locations were significant except for banking slope length. Road width, longitudinal gradients, banking and cutting slope length by slope gradients were not significantly different and banking slope gradients in the range less than $30^{\circ}$, from $30^{\circ}$ to $35^{\circ}$ and more than $40^{\circ}$ and cutting slope gradients were significantly different for all areas. Road width, longitudinal gradients, banking slope length by soil types were not significantly different and others were significantly different. All factors related to the road structures by road position were significant except for cutting slope gradients.

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Factors Affecting Ambient Monoterpene Levels in a Pine Forest

  • Kim, Jo-Chun;Kim, Ki-Hyun
    • Journal of Environmental Science International
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    • v.11 no.8
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    • pp.811-818
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    • 2002
  • The concentration levels of monoterpenes, including ${\alpha}$- and ${\beta}$-pinene, were measured in a pine forest in Florida, USA, over about one year. Based on this measurement data, the current study then investigated the factors affecting the environmental behavior of monoterpenes. Despite a moderately weak temperature variability in the study area, the temperature dependence of the concentration variations was still evident. The concentrations of the two pinenes were significantly affected by changes in the air temperature, as indicated by strong correlations with temperature. A close relation among the measured parameters was also found between the ${\beta}$-pinene and ozone concentrations, which is also in line with previous findings from other studies. In addition, it was interesting to note that the ${\beta}$/${\alpha}$ pinene concentration ratio exhibited a strong inverse correlation to temperature, with the seasonal mean ranging from 0.51(summer) to 0.93(winter). Accordingly, the current results indicate that, in a forest environment, the major terpene species concentrations are affected by both meteorological conditions and chemical reactions.

New record of Folsomia quadrioculata(Tullberg, 1871) and redescription of Folsomia octoculata(Handschin, 1925) from the forest of South Korea

  • Lee, Yun-Sik;Cho, Kijong;Park, Kyung-Hwa
    • Korean Journal of Environmental Biology
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    • v.37 no.1
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    • pp.1-7
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    • 2019
  • During a recent study to understand an interaction of Collembola community and their environmental factors, two species in the genus Folsomia, F. quadrioculata Tullberg 1871 and F. octoculata Handschin 1925, were found in the forest of South Korea. From 2013 to 2015, these two species were sampled from six mountains and F. quadrioculata or F. octoculata was the dominant species in 5 sampling sites among 6 sampling sites. F. quadriocualta and F. octoculata were found in litter of deciduous and pine forest, respectively. Therefore, the major tree species seems to be one of the important factors determining their habitat. F. quadiroculata is newly recorded from the Korean Peninsula and F. octoculata is redescribed based on new materials from South Korea.

The Change in Fuel Moisture Contents on the Forest Floor after Rainfall

  • Songhee Han;Heemun Chae
    • Journal of Forest and Environmental Science
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    • v.39 no.4
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    • pp.235-245
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    • 2023
  • Forest fuel moisture content is a crucial factor influencing the combustion rate and fuel consumption during forest fires, significantly impacting the occurrence and spread of wildfires. In this study, meteorological data were gathered using a meteorological measuring device (HOBO data logger) installed in the south and north slopes of Kangwon National University Forest, as well as on bare land outside the forest, from November 1, 2021, to October 31, 2022. The objective was to analyze the relationship between meteorological data and fuel moisture content. Fuel moisture content from the ground cover on the south and north slopes was collected. Fallen leaves on the ground were utilized, with a focus on broad-leaved trees (Prunus serrulata, Quercus dentata, Quercus mongolica, and Castanea crenata) and coniferous trees (Pinus densiflora and Pinus koraiensis), categorized by species. Additionally, correlation analysis with fuel moisture content was conducted using temperature (average, maximum, and minimum), humidity (average, minimum), illuminance (average, maximum, and minimum), and wind speed (average, maximum, and minimum) data collected by meteorological measuring devices in the study area. The results indicated a significant correlation between meteorological factors such as temperature, humidity, illuminance, and wind speed, and the moisture content of fuels. Notably, exceptions were observed for the moisture content of the on the north slope and that of the ground cover of Prunus serrulata and Castanea crenata.

Water Erosion and Its Combating Measures in Loess Plateau, China (중국 황토고원지구의 물침식과 대책)

  • Chun, Kun-Woo;Lim, Young-Hyup;Oh, Jeong-Soo;Yoon, Taek-Seong;Park, Ki-Hyung
    • Journal of Forest and Environmental Science
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    • v.26 no.3
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    • pp.181-192
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    • 2010
  • Water erosion is progressing in the Loess Plateau, especially in gullies, and the sediment runoff to the Yellow River amounts to 975 million tons every year. Natural factors for water erosion include climate, soil, geological feature, terrain and vegetation. Many development projects due to the increasing population reduced the forest coverage ratio to 10%, and 200 million people in the downstream area are suffering from the damage during intense rainfall. Accordingly, the Chinese government is continuously trying to efficiently prevent the erosion by establishing measures for water erosion, including fish-scale pits, terrace technique, and check dams.

Classification of Urban Forest Types and its Application Methods for Forests Creation and Management (도시숲 조성 및 관리를 위한 도시숲 유형화 및 적용방안)

  • Lee, Dong-Kun;Kim, Eun-Young;Song, Won-Kyong;Park, Chan;Choe, Hye-Young
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.12 no.5
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    • pp.101-109
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    • 2009
  • There are increasing needs about creation and sustainable management of urban forest for environmental conservation and recreational service for citizen. However, it is difficult for local governments to create or manage urban forest in recreational or conservational way. The purpose of this study is to classify the urban forest types by considering its geographical feature, biological and sociological characteristics in order to suggest a guide to local governments about effective creation or management of urban forest. In this study, we extracted common characteristics of the selected five indicators. Factors about urban forest are divided into two groups. Factors were named according to the variables as 'Urban Forest Naturalness', and 'High Accessibility and Disturbed by Human.' In addition, we classified urban forests into four types in this study. The type I of urban forest is a large forest and has high naturalness such as Mt. Bukhan and Mt. Gwanak. The type II is fragmented to large forests by developmental projects. The type III is flat and has high accessibility such as forest behind Seonjeongneung. The type IV is located near residential area such as Mt. Ansan, Mt. Inwang and Mt. Bonghwa. It is possible to set up recreational area for citizens and ecological networks for species by the research of the urban forest type. The results of the study, classification of urban forest types and its application, contribute to provide a guide for local governments to create or manage urban forests effectively.

Essential Oil Yields and Chemical Compositions of Chamaecyparis obtuse Obtained from Various Populations and Environmental Factors

  • Kang, Young Min;Min, Ji Yun;Choi, Myung Suk
    • Journal of Forest and Environmental Science
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    • v.30 no.3
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    • pp.285-292
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    • 2014
  • Essential oil yields and chemical compositions from 5 populations of Chamaecyparis obtusa with several environmental factors were investigated through essential oil extracted distillation apparatus and metabolite profiling by GC-MS analysis. Among the populations, content of essential oil at Gokseong was significantly higher than other populations. To compare the several environmental factors affecting on chemical composition and essential oil yields from C. obtuse at Gokseong, the environmental factors (soil condition, temperature, humidity, and moisture content) were measured during 1 year. The essential oils at Goksung based on humidity on March, July, and November was significantly different from other months. The essential oils at Goksung based on temperature on July and August was significantly different from other months. The essential oils at Goksung based on the moisture content on September were significantly different from other months. The percentage of T-N, OM, and yield of oil at Gokseong were significantly different on from other populations. The main constituents of C. obtusa at all populations were ${\alpha}$-pinene, ${\beta}$-pinene, ${\alpha}$-terpinene, ${\gamma}$-terpinene, terpinene-4-ol, isobonyl acetate, terpinyl acetate, and cedar acetate. Specially, Essential oil compositions (%) of ${\alpha}$-terpinene and cedar acetate were higher at Gokseong than at other populations. The chemical compositions of essential oils were variable depend on populations and environmental conditions. Therefore, this study might be used as fundamental research on study for selection of high productive terpenoids and for understanding about biosynthesis of essential oils in C. obtusa.

Productivity and Cost of Tree-length Harvesting Using Cable Yarding System in a Larch (Larix leptolepis) Clear-cutting Stand

  • Jeong, Eungjin;Cho, Koohyun;Cho, Minjae;Choi, Byoungkoo;Cha, Dusong
    • Journal of Forest and Environmental Science
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    • v.33 no.2
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    • pp.147-153
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    • 2017
  • The purpose of this study was to examine productivity and cost of tree-length harvesting using cable yarding system in a larch (Larix leptolepis) clear-cutting stand located in Pyeongchang-gun, Gangwon-do. We used tree-length harvesting method using cable yarding system with a tower yarder HAM300. The productivity was $17.6m^3/hr$ for felling, $12.4m^3/hr$ for delimbing, $4.2m^3/hr$ for yarding, and $8.1m^3/hr$ for processing. The total cost of the harvesting system was $48,381won/m^3$, which was majorly composed of yarding operation cost, at $40,169won/m^3$ (79.3%), while felling had the lowest cost at $1,154won/m^3$ (4.1%). Major factors affecting felling and processing productivity was tree volume and the number and thickness of branches for delimbing productivity. In addition, we suggest that training and education for machine operators were critical to improve yarding productivity.