• Korean Journal of Plant Resources
• /
• v.13 no.3
• /
• pp.188-194
• /
• 2000

This study was carried out to obtain the optimum cultivation conditions of wild ornamental plant resources, Dicentra spectabilis L. The altitude of the habitat was ranged from 630m to 690m in Mt. Gujeol. Most of the habitat faced toward the northeast aspect and the gradient was ranged from 25 to 33 degrees. The light intensity of Dicentra community was 14,000lux on the average, and it was tendency to decrease by foliation of other woody plants. The appearance number of Dicentra per quadrat was 30 individuals on the average, and total appearance species in all quadrat surveyed was 52 taxa. Among them, Quercus mongolica, Lindera obtusiloba, Corylus heterophylla, Cornus controversa, woody plants, Corydalis speciosa, Pseudostellaria heterophylla, Artemisia keiskeana, Dryopteris crassirhizoma, Arisaema amurense var. serratum, Carex siroumensis, and Chloranthus japonicus, herbaceous plants, were showed as dominant species. Soil acidity in the habitat was 5.15 to 5.96, and average content of soil moisture was 32.6%. The contents of average organic matter, $P_2O_5$, K, Ca, and Mg were 1.99%, 14mg/kg, 0.55me/100g, 15.2me/100g, and 3.3me/100g, respectively. Electron conductivity was ranged from 0.50 to 0.76dS/m. Also, the average air temperature of May and June was 14.2$^{\circ}C$ and 19.4$^{\circ}C$, respectively.

• Korean Journal of Plant Resources
• /
• v.23 no.2
• /
• pp.179-186
• /
• 2010

This study was conducted to provide basic information for conservation and restoration through investigation of vegetation and soil condition of Megaleranthis saniculifolia Ohwi, Korean endemic species, in Mt. Halla, Jeju Island. Very few individuals were discontinuously distributed and restricted at 1,075 m above sea level, very steep slope ($60-70^{\circ}C$), rocky area of north face of Eorimok Valley. For investigation of environmental condition, we established two $10\;{\times}\;10\;m$ quadrats in the habitats and one control quadrat. Twenty-four species were found at site 1 under 10-12 m Carpinus laxiflora tree layer (35%) and soil conditions are pH 5.9, moisture content (field capacity) 9.39%, organic carbon 8.22% and organic matter 14.17%, respectively. Site2, 15 taxa were found under 8-12 m Platycarya strobilacea tree layer (40%) and soil conditions are pH 5.07, moisture content 4.99%, organic carbon 5.34% and 9.21 percentage of organic matter. In the control quadrat, 14 taxa were found under 10 m Carpinus laxiflora tree layer (10%) and soil conditions are pH 5.27, moisture content 6.23%, organic carbon 4.74% and organic matter 8.17%, respectively. The principal causes of threat which were investigated in this study are competition among company, very steep slopes, artificial management of valley. For restoration and conservation of habitats, it is needed to suitable plans.

• Korean Journal of Soil Science and Fertilizer
• /
• v.44 no.6
• /
• pp.1144-1149
• /
• 2011

The occurrence of Korean pine (Pinus koraiensis) advance growth has been noticed in the deciduous oak forest being adjacent to the mature Korean pine plantation. the korean pine seedlings in the forest were regenerated naturally from harvested and transported Korean pine seeds and cones by rodents, mainly red squirrels. Mongolian oak (Quercus bariabilis), which formed dominant overstory, had close-to-normal distributions of height, diameter and age classes. Korean pine, which dominated the understory, had the reverse J-shaped height, diameter and age distributions that are expected of a shade tolerant species. Growing in the summer shade of the oak, Korean pine seedling had slow, but steady height growth during the past four decades. Total biomass of Korean pine seedling ranged from $2,835-8,541kg\;ha^{-1}$ and biomass allocation of Korean pine seedling was follows : stem (with bark) > foliage > branches > roots. Korean pine seedlings allocated more biomass to foliage and branches compare to planted Korean pine. The smaller root/shoot ratio of Korean pine seedling in the site is to believed to be result of competition for light. Contents of N and K for Korean pine seedling were greatest in foliage follow by branches, stem ad roots, while content of P was greater in the order of foliage > roots > stem > branches.

• Korean Journal of Environment and Ecology
• /
• v.33 no.1
• /
• pp.86-106
• /
• 2019

We investigated the environmental conditions of natural habitats of T. nuda. The species was found on rocky northern hills ($60{\sim}90^{\circ}$) near the stream where the sea level ranges 95~145m. The average annual temperature of the habitats was lower than other places of South Korea. The differences of the lowest and the highest of the year was significantly huge than any other places. Plants were growing at the edge of stream that water reached but not submerged. Most of plants were found in North, Northeast or Northwest. It is suggested that these species require moist and low sunlight for growth. The common vegetation along with the T. nuda includes Mukdenia rossii, Selaginella rossii, Calamagrostis epigeios, and Rhododendron yedoense f. poukhanense. The dominance values and sociability of T. nuda were below 3 in all studied habitats and the variance of the number of individuals among the habitats was very high. As the optimum habitats for the T. nuda are decreasing due to the extreme precipitation patterns. It is also expected that the number of T. nuda will be decreased in the future. Therefore restoration activity in situ or ex situ must be conducted to conserve this valuable plant species.

• Journal of the Korean Institute of Landscape Architecture
• /
• v.50 no.2
• /
• pp.41-63
• /
• 2022

The purpose of this study is to secure objective and precise data through ecosystem monitoring, to reveal ecological characteristics through comparison and analysis with past survey data, and to accumulate basic data for diagnosing the current situation and predicting changes in the ecosystem. The target site is the 'Quercus mongolica forest on the Buksa-myeon of Namsan', which was designated as an Ecological Landscape Conservation Area (ELCA) of Seoul in July 2006. The research contents are analysis of soil environment change (1986~2016), change of actual vegetation (1978~2016), and change of plant community structure (1994~2016). A total of 8 fixed surveys (400~1,200m²) were established in 1994 and 2000. Analysis items are importance value, species and population, and Shannon's species diversity. The soil environment of Namsan is acidic (pH 4.40 in 2016), which is expected to have a negative impact on tree growth and vegetation structure due to its low capacity for exchangeable cations. Quercus mongolica forest in Namsan is mainly distributed on the northern slopes. The actual vegetation area changed from 49.4% in 1978 → 80.7% in 1986 → 82.4% in 2000 → 88.3% in 2005 → 88.3% in 2009 → 70.3% in 2016. In 2016, the forest decreased by 18% compared to 2009. While there was increased growth of Quercus mongolica in the tree layer from 2009 to 2016, the overall decline in vegetation area was due to logging and fumigation management following the spread of oak wilt in 2012. As for the changes in the plant community structure, Quercus mongolica of the tree layer was damaged by oak wilt, and the potential vegetation that can form the next generation was ambiguous. In the subtree layer, the force of urbanization tree species such as Styrax japonicus, Sorbus alnifolia, and Acer palmatum. was maintained or increased. In the shrub layer, the number of trees and species increased significantly due to the open tree crown, and accordingly, the species diversity of Shannon for woody plants also increased. In Quercus mongolica forest of Namsan, various ecological changes are occurring due to the effects of urban environments such as air pollution and acid rain, the limitation of Quercus mongolica pure forest due to oak wilt, and the introduction of exotic species, thus, it is necessary to establish a management plan through continuous monitoring.

• Korean Journal of Environmental Biology
• /
• v.17 no.1
• /
• pp.35-50
• /
• 1999

The relationship between floristic composition and soil environmental conditions was investigated in the forest vegetation of Mt. Paekun. The forest vegetation unit of Mt. Paekun was divided into six plant communities by Zurich-Montpellier method, such as Quercus mongelica community (Typical subcommunity, Rhododendron schlippenbaohii subcommunity), Q. variabilis community, Fraxinus rhynchophylla community, Pinus densiflora community, Larix Eeptolepis community and Pinus koraiensis community. Q. mongolica community group was distributed at the altitude over 500 meter, Q. variabilis and P. densiflora communities appeared on the southwestern slope at the altitudes of 600 ~ 700 m and 290 ~ 700 m. However, L. leptolepis and P. koraiensis plantation were distributed at lower altitude, on hillside or around homestead. The DBH class distribution of dominant species in each community showed that Q. mongolica had 10.9 individuals/a at 6~10 cm class, Q. variabilis 2.5 individuals/a at 11~15 cm class, P. densiflora 1.8 individuals/a at 26~30 cm class, F. rhynchophylla 3.3 individuals/a at 2~5 cm class, and L. leptolepis 5.9 individuals/a at 11~ 15 cm class. Q. mongolica and Q. variabilis communities showed a stable bell-shaped pattern of distribution. The contents of organic matters and soil water, and cation exchange capacity of the soil increased, and the pH decreased as the altitude gets higher increased altitude at the each communities. The contents of the soil water and organic matters of the forest soil collected in Q. mongolica community were in the 17.81% to 51.20% and 5.51% to 14.90%, respectively. These tendency is similar to the contents of N, P and K, but those of Ca, Mg, and CEC was lower than in other communities. Cation exchange capacity was suspected to be correlated to the pH. The hypothetical successional sere of the forest vegetation of Mt. Paekun is as follows: Pinus densiflora community longrightarrowQ. variabilis community longrightarrowQ. mongolica community.

• Journal of the Korean association of regional geographers
• /
• v.9 no.3
• /
• pp.373-384
• /
• 2003

This study analyses the soil loss due to cropland increase in the Hoeryeung area of northeast Korea, using Landsat images of 1987 TM and 2001 ETM, together with DTED, soil and geological maps, and rainfall data of 20 years. Items of land cover and land use were categorized as cropland, settlement, forest, river zone, and sand deposit by supervised classification with spectral bands 1, 2 and 3. RUSLE model is used for estimation of soil loss, and AML language for calculation of soil loss volumes. Fourier transformation method is used for unification of the geographical grids between Landsat images and DTED. GTD was selected from 1:50,000 topographic map. Main sources of soil losses over 100 ton/year may be the river zone and settlement in the both times of 1987 and 2001, but the image of the 2001 shows that sources areas have developed up to the higher mountain slopes. In the cropland average, increases of hight and gradient are 24m and $0.8^{\circ}$ from 1987 to 2001. In the case of new developed cropland, average increases are 75m and $2.5^{\circ}$, and highest soil loss has occurred at the elevation between 300 and 500m. The soil loss 57 ton of 1987 year increased 85 ton of 2001 year. Soil loss is highest in $30{\sim}50^{\circ}$ slope zones in both years, but in 2001 year, soil loss increased under $30^{\circ}$ zones. The size of area over 200 ton/year, indicating higher risk of landslides, have increased from $28.6km^2$ of 1987 year to $48.8km^2$ of 2001 year.

• Journal of Korea Water Resources Association
• /
• v.52 no.1
• /
• pp.51-60
• /
• 2019

The major purpose of this study is to construct an in-situ soil moisture verification network employing Frequency Domain Reflectometry (FDR) sensors for Cosmic-ray soil moisture observation system operation as well as long-term field-scale soil moisture monitoring. The test bed of Cosmic-ray and FDR verification network system was established at the Sulma Catchment, in connection with the existing instrumentations for integrated data provision of various hydrologic variables. This test bed includes one Cosmic-ray Neutron Probe (CRNP) and ten FDR stations with four different measurement depths (10 cm, 20 cm, 30 cm, and 40 cm) at each station, and has been operating since July 2018. Furthermore, to assess the reliability of the in-situ verification network, the volumetric water content data measured by FDR sensors were compared to those calculated through the core sampling method. The evaluation results of FDR sensors- measured soil moisture against sampling method during the study period indicated a reasonable agreement, with average values of $bias=-0.03m^3/m^3$ and RMSE $0.03m^3/m^3$, revealing that this FDR network is adequate to provide long-term reliable field-scale soil moisture monitoring at Sulmacheon basin. In addition, soil moisture time series observed at all FDR stations during the study period generally respond well to the rainfall events; and at some locations, the characteristics of rainfall water intercepted by canopy were also identified. The Temporal Stability Analysis (TSA) was performed for all FDR stations located within the CRNP footprint at each measurement depth to determine the representative locations for field-average soil moisture at different soil profiles of the verification network. The TSA results showed that superior performances were obtained at FDR 5 for 10 cm depth, FDR 8 for 20 cm depth, FDR2 for 30 cm depth, and FDR1 for 40 cm depth, respectively; demonstrating that those aforementioned stations can be regarded as temporal stable locations to represent field mean soil moisture measurements at their corresponding measurement depths. Although the limit on study duration has been presented, the analysis results of this study can provide useful knowledge on soil moisture variability and stability at the test bed, as well as supporting the utilization of the Cosmic-ray observation system for long-term field-scale soil moisture monitoring.

• The Journal of Engineering Geology
• /
• v.23 no.2
• /
• pp.161-170
• /
• 2013

We analyzed the effect of changing water level and turbidity on plants that serve to maintain slope stability on levees. In this experiment, soil collected from upstream of Imha Dam was placed in a water tank and planted with river plants of the Salix species: Salix gracilistyla, S. koreensis, and S. glanduosa. Plant regrowth was analyzed stage-by-stage during a recovery period. In addition, we assessed the tolerance of the plants to concentrated torrential rainfall and examined their recovery rates. The results indicate that in the case of these three Salix species, which are the most prevalent river plants in Korea, stem growth is arrested following serious damage and high turbidity. The possibility of regrowth was very low during the 20-day non-submerged recovery period. Although the number of leaves initially decreased during this period, subsequent regrowth was reasonably high: recovery in S. gracilistyla, S. koreensis, and S. glanduosa was up to 59.3%, 251.3%, and 148.4% respectively, compared with the initial condition.

• Journal of The Geomorphological Association of Korea
• /
• v.18 no.4
• /
• pp.1-15
• /
• 2011

This work is to review the granite landforms studies by Korean geographers. It is verified that geomorphlogical characteristics of granite present landscapes characterized by 1) in case of mountains, are difficultly or irregularly weathered, so as to develop rocky forms such as domes, cliffs, and tors ; 2) in case of stream valley that is inter-massif lowland, low relief hills and flood plains with alluvium. All these facts owe to the difference of weathering mode granite properties. The granite hills and alluvial plains of southwestern coastal parts in Korean peninsula is low undulatory and large owing not only to the existence of highly weathered granitic regolith, but also to frequent flooding. Cultivated brownish field, orchard, meadow and forest are located at granite hills. On the other hand paddy rice field at granite alluvial plains. Korean peninsula have endured erodible geomorphlogical processes since Miocene when warping it up. Therefore many intermontane basins are located on the weathered granite areas which are surrounded by mountains composed of much less Precambrian gneiss complex. In fact, intermontane basin is mainly linear fault-line valley. The landforms of the intermontane basins are characterized by gentle piedmont slopes, alluvial fans, fluvial terraces and alluvial plains.