• Journal of Korean Society of Forest Science
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• v.101 no.3
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• pp.333-343
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• 2012

In-stream large wood (LW) has a critical impact on the geomorphic characteristics relevant to ecosystem management and disaster prevention, yet relatively little is known about variations in its dynamics and subsequent export on the watershed-scale perspective in Korea. Here we review variations in the dynamics and subsequent export of LW as a function of stream size, which is appropriate for Korean mountain streams. In upstream channels with narrow bankfull widths and low stream discharges, a massive amount of LW, resulting from forest dynamics and hillslope processes, may persist for several decades on valley floor. These pieces, however, are eventually transported during infrequent debris flows from small tributaries, as well as peak hydrology in main-stem channels. During the transport, these pieces suffer fragmentation caused by frictions with boulders, and stream bank and bed. Although infrequent, these events can be dominant processes in the export of significant amounts of LW from upstream channel networks. In downstream channels with wide bankfull widths and high stream discharges, LW is dominantly recruited by forest dynamics and bank erosion only at locations where the channel is adjacent to mature riparian forests. With the LW pieces that are supplied from the upstream, these pieces are continuously transported downstream during rainfall events. This leads to further fragmentation of the LW pieces, which increases their transportability. With decreasing stream-bed slope, these floated LW pieces, however, can be stored and form logjams at various depositional sites, which were developed by interaction between channel forms and floodplains. These pieces may decay for decades and be subsequently transported as particulate or dissolved organic materials, resulting in the limitation of LW fluvial export from the systems. However, in Korea, such depositional sites were developed in the extremely limited streams with a large dimension and no flood history for decades, and thus it does not be expected that the reduction of LW export amount, which can be caused by the long-term storage. Our review presents a generalized view of LW processing and is relevant to ecosystem management and disaster prevention for Korean mountain streams.

• Journal of Korean Society of Forest Science
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• v.87 no.4
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• pp.535-542
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• 1998

This study was carried out for the purpose of supplying the basic data for artificial forestation, natural regeneration and ecological conservation etc., and obtaining information on alpine vegetation, by establishing vegetation units on the basis of phytosociological classification of community and studying growth pattern on the basis of species composition, hierarchy structure and population dynamics, for Taxes cuspidata naturally growing at the alpine districts in Korea. The importance value of Taxus cuspidata by districts mostly showed above 100 in the upper story but at Mt. Chiri and Mt. Hanra communities its value was comparatively low. In the middle story it showed lower value than that of upper story and not quite showed at Mt. Chiri. Taxus cuspidata communities in the lower story were only in Mt. Hanra, Mt. Odae and Mt. Sobaek, and their importance values were about 10 which were relatively low values. The communities were classified into five groups as Taxus cuspidata-Males baccata var. mandshurica, Taxus cuspidata-Abies nephrolepis, Taxus cuspidata-Abies koreana, Taxus cuspidata-Acer mono and Taxus cuspidata-Euonymus quelpaertensis by TWINSPAN analysis. Taxus cuspidata-Abies koreana community was distributed at the northern aspect of the mountain ridges and at higher elevation than other communities and distributed. Taxus cuspidata-Acer mono community was relatively low than the others and distributed at the hillsides of mountain. And Taxus cuspidata-Euonymus quelpaertensis communities were distributed at the relatively high elevation and northern and eastern aspect of the mountain tap, and Taxus cuspidata-Malus baccata var. mandshurica communities were distributed at the medium elevation, and southern and eastern aspect of the mountain ridge. In the relation between communities and environmental factors, it was correlated with aspect, elevation and topography at the first axis, and elevation, slope at the second axis.

• Korean Journal of Environment and Ecology
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• v.24 no.5
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• pp.582-590
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• 2010

Baekdudaegan field survey has been proposed and presented as a various plan such as field survey analysis, management and restoration plan, etc. Whereas, the concerns of the Jeongmaek has increased continuously, nevertheless there is no research of present condition for Jeongmaek. This paper is to contribute to suggest for management and restoration as a basic study of vegetation structure in Yongso valley. We set up 30 plots($100m^2$) to verify the vegetation structure. As a result of classification analysis used by DCA, the type of 5 communities i.e. Pinus densiflora community, Betula schmidtii community, Populus maximowiczii community, Quercus mongolica community, Q. variabilis community were the most representative of Yongso valley vegetation communities. P. densiflora community was mainly distributed in the ridge of mountain, ridge of steep slope and stony area. In that reason, they avoid to compete with B. schmidtii community and Q. spp. community. In addition, the appearance of Rhododendron micranthum was mainly characteristics in the P. densiflora community. Species diversity indices(H') of groups were ranged from 0.7914~0.9942, the tree ages were 30~115 years. According to these results, the forests of Yongso valley not only form muti-layer vegetation structures but also have a great ecological value for protection and preservation.

• Journal of Plant Biology
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• v.35 no.4
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• pp.393-401
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• 1992

A new species of Dictyostelium, isolated from the subalpine coniferous forests of Halla mountain, was described. The most noteworthy morphological characteristics of this new species were broad petal-like aggregates, concentrated long branches near the bases, typically clustered and delicate sorocarps. DictyosLeLium jloridurn sp. novo was also characterized by 1) elliptical spores with distinctive polar granules, 2) strongly tapering and rough surface of sorophores, 3) frequent occurrence of expanded conical bases, 4) the congealed slime substrate where the several bases were anchored into, 5) compound and c1avata tips. It was quite sensitive to environmental conditions, particularly temperature. Macrocysts and microcysts were not observed. This species can be cultured satisfactorily in assosiation with Esch'||'&'||'pound;richia coLi upon agar media of weak nutrient content, 0_1% lactosepeptone, under diffuse light and darkness. Optimum temperature for growth and develoi)ment was about $18-22^{\circ}C$, below that of most other species of the family.

• Korean Journal of Remote Sensing
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• v.36 no.1
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• pp.29-39
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• 2020

Forest fire is a critical disaster that causes massive destruction of forest ecosystem and economic loss. Hence, accurate estimation of the burned area is important for evaluation of the degree of damage and for preparing baseline data for recovery. Since most of the area size damaged by wildfires in Korea is less than 1 ha, it is necessary to use satellite or drone images with a resolution of less than 10m for detecting the damage area. This paper aims to detect wildfire-damaged area from a Kompsat-3 image using the indices such as NDVI (normalized difference vegetation index) and FBI (fire burn index) and to examine the classification characteristics according to the methods such as Otsu thresholding and ISODATA(iterative self-organizing data analysis technique). To mitigate the salt-and-pepper phenomenon of the pixel-based classification, a gaussian filter was applied to the images of NDVI and FBI. Otsu thresholding and ISODATA could distinguish the burned forest from normal forest appropriately, and the salt-and-pepper phenomenon at the boundaries of burned forest was reduced by the gaussian filter. The result from ISODATA with gaussian filter using NDVI was closest to the official record of damage area (56.9 ha) published by the Korea Forest Service. Unlike Otsu thresholding for binary classification,since the ISODATA categorizes the images into multiple classes such as(1)severely burned area, (2) moderately burned area, (3) mixture of burned and unburned areas, and (4) unburned area, the characteristics of the boundaries consisting of burned and normal forests can be better expressed. It is expected that our approach can be utilized for the high-resolution images obtained from other satellites and drones.

• Journal of the Korean Association of Geographic Information Studies
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• v.22 no.4
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• pp.24-38
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• 2019

Due to the dramatic spatial changes caused by industrialization, environmental problems such as air pollution and urban heat island phenomenon, etc. are occurring in cities. In this case, the wind corridor, which is a passage through which fresh and cool air generated in forests outside cities move to the downtown, can be used as a spatial planning method for improving urban environmental problems. Cold air is determined by the characteristics of the flow depending on the topography and land use of cities, and based on this, the medium- and long-term plan should be established. Therefore, this study analyzed the flow of cold air at night through the KLAM_21 model in Suwon-si, Gyeonggi-do, to prepare the basic data required to apply the wind corridors. As a result, it turned out that cold air of Suwon-si was mainly generated from Gwanggyo Mountain that is a large mountain area in the north, and flowed into the urbanization promotion area, and about three hours after sunset, cold air flowed into the downtown. By district, the depth, wind speed, and direction of the cold air layer were formed differently according to the characteristics of the topography and land use. In the areas where large forests were adjacent, the flow of cold air was active. There are three main wind corridors where cold air flows to the downtown of Suwon-si, all of which are formed around rivers. Especially, if the connection between rivers and the surrounding green areas is high, the effect of wind corridors is found to be significant. In order to utilize the wind corridors of Suwon-si, based on the results of this study, it is necessary to make climate maps through actual survey and complex analysis of cold air flow and establish mid-to-long-term plans for the conservation and expansion of major wind corridors.

• Journal of Korean Society of Forest Science
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• v.101 no.3
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• pp.501-508
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• 2012

This study was carried out to compare species diversity of soil bacteria from Baekdudaegan mountain forests (Bonghwa-gun, Mungyeong-si and Sangju-si) in Gyeongsangbuk-do and to analyze the effects of soil environments on diversity and population of soil bacteria. Soil bacteria were isolated from soil samples by streak plate method, and identified by DNA extaction and 16S rDNA sequence analyses. The population of soil bacteria from the soil samples of Bonghwa-gun was the highest with $5.1{\times}10^5cfu/g$, and followed by those from Mungyeong-si and Sangju-si with $1.9{\times}10^5cfu/g$ and $1.1{\times}10^5cfu/g$, respectively. The population of soil bacteria from surface layer soil was the highest, and then gradually decreased according to soil depth. The increase in population of soil bacteria from soil samples of different sites was correlated with the increase of the altitude of soil sampling site, depth of A horizon, liquid phase among three phases of soil, water content and bulk density of soil. Two hundreds and sixty eight bacterial colonies from Bonghwa-gun were classified into 10 species, 8 genera. One hundred and thirty four bacterial colonies from Mungyeong-si were classified into 15 species, 9 genera. Forty four bacterial colonies from Sangju-si were classified into 5 species, 2 genera. The dominant species (occupancy rate) from Bonghwa-gun and Mungyeong-si were Bacillus weihenstephanensis (36% and 40%, respectively), and Sangju-si was Bacillus cereus (39%). The relationships between soil environment and community structure of soil bacteria were analyzed statistically by using ecological indices. The diversity, evenness and dominance indices of soil bacteria were 6.30, 2.04 and 0.59 in Bonghwa-gun, 9.09, 2.94 and 0.51 in Mungyeong-si, and 4.55, 2.34 and 0.71 in Sangju-si, respectively. The diversity and evenness indices were increased by the increase of water content, drainage condition and gravel content of soil, while the dominance index was decreased.

• Journal of Korean Society of Forest Science
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• v.79 no.2
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• pp.144-161
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• 1990

Pine forest communities developed in Mt. Palgong, southeastern Korea, were studied phytosociologically, with special reference to multiple management of local forests, and were classified into two communities, Pinus densiflora - Quercus mongolica community(I : mountain forest) and P. densiflora-Climbing plants community (II : valley forest) and six subgroups accompanied by several subgroups. Judging from the coincidence method, the division of communities (vegetation units) was closely related to altitude and topography. Based on vegetation units, a vertical distribution map of pine forest communities was prepared. The species composition(%) of pine forest communities under stratification, in upper and lower tree layer, teas I higher than II, in middle and shrubs lacer II higher than I (Total : Upper 15.5%, Middle 28.4%, Lower 34.6%. Shrubs 21.5%. Sum of mean coverage%i of understory vegetation was II twice as high as I (Total. shrubs 28.4%. forbs 11.4%, Graminoids 11.8%, ferns 1.0%). Based on constance, coverage and d.b.h. class etc., an actual growth and occurrence table of tree species and understory vegetation by vegetation unity were prepared, and could assume a criterion for judging potential dominance-growth conditions.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.30 no.2
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• pp.101-109
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• 2012

Traditional village forests in Jeju Island represent unique cultural landscape with a history of more than several hundred years as a national cultural asset in Korea. In this paper, the characteristics and meaning of traditional village forests in Jeju Island was compared with the Dangsan and Bibo forests at inland. There are 368 Oreums, parasitic volcano, and 391 shrines of Dang(Divine place) in Jeju. Life, culture and tradition of rural villages are all connected with the Dang and Oreum in Jeju. It has been found from this study that the village in Jeju were established as a cultural landscape on the surface of natural landscape. The features of traditional villages focused on the Dang and Oreum in Jeju Island were similar to the Dangsan and Bibo forestsat inland villages. The Oreum represents mountain and the Pojedan forest is newly found in Sangmyung-ri. The seashore areas are covered by vaocanic rocks in Jeju and large scale windbreaks are hardly found. The stone tower at Sinheung-ri built for blocking sand movement represents Bibo forest. The special attribute of the Dang in Jeju is that it is close to real life and believers are still remain. In 2009, the Jeju Chilmeoridang Yeongdeunggut ritual was nominated as an Intangible Cultural Heritage of Humanity by UNESCO. The shrine of Dang, however, has been degraded fast by construction of seashore road and Jeju Olle trail path. As for the world cultural heritage discussed at international conferences, it is important that there is sustainability on the right to enjoy cultural heritage. Integrated efforts from local residents, local governments and national government are needed to set up a management scheme for the Dang culture. Rural villages in Jeju with the Dang and Oreum are expected to get an international attention as to have traditional cultural landscapes of Korea.

• Journal of Korean Society of Forest Science
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• v.106 no.3
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• pp.310-319
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• 2017

This study categorized the damaged trees by Supervised Classification using time-series-aerial photographs of Bukhan, Cheonggae and Suri mountains because oak wilt disease seemed to be concentrated in the metropolitan regions. In order to analyze the spatial characteristics of the damaged areas, the geographical characteristics such as elevation and slope were statistically analyzed to confirm their strong correlation. Based on the results from the statistical analysis of Moran's I, we have retrieved the following: (i) the value of Moran's I in Bukhan mountain is estimated to be 0.25, 0.32, and 0.24 in 2009, 2010 and 2012, respectively. (ii) the value of Moran's I in Cheonggye mountain estimated to be 0.26, 0.32 and 0.22 in 2010, 2012 and 2014, respectively and (iii) the value of Moran's I in Suri mountain estimated to be 0.42 and 0.42 in 2012 and 2014. respectively. These numbers suggest that the damaged trees are distributed in clusters. In addition, we conducted hotspot analysis to identify how the damaged tree clusters shift over time and we were able to verify that hotspots move in time series. According to our research outcome from the analysis of the entire hotspot areas (z-score>1.65), there were 80 percent probability of oak wilt disease occurring in the broadleaf or mixed-stand forests with elevation of 200~400 m and slope of 20~40 degrees. This result indicates that oak wilt disease hotspots can occur or shift into areas with the above geographical features or forest conditions. Therefore, this research outcome can be used as a basic resource when predicting the oak wilt disease spread-patterns, and it can also prevent disease and insect pest related harms to assist the policy makers to better implement the necessary solutions.