• Korean Journal of Ecology and Environment
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• v.53 no.4
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• pp.390-407
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• 2020

This study was carried out to evaluate the restoration effect in the restored Yangjae stream and to draw up an adaptive management plan based on the results. As the result of evaluation on the restoration effect, the restored Yangjae stream was evaluated with low naturalness in both terms of the morphology of the stream and the composition and spatial distribution of vegetation. The diverse functional groups were introduced in the vegetation restoration, but the flooding regime, which is significant in the spatial distribution of riparian vegetation, were not correctly reflected. Exotic species or species that were not ecologically suitable for the location were introduced on the embankment and thus a measure to improve those problems is required. As the ecological principle was not reflected in the restoration plan, the stream was constructed as the double terrace structure. Therefore, the width of the waterway was narrowed further, and the waterfront was not designed to accommodate changes from flooding disturbance, making the micro-topography of the stream simpler and the naturalness lower. The adaptive management plan was prepared to improve those problems, and a plan for creating an ecological network was recommended to enhance the restoration effect.

• Journal of the Korean earth science society
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• v.43 no.6
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• pp.680-690
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• 2022

Tephrochronology uses regional tephra for age dating and stratigraphic correlations. Regional tephras are important in Quaternary geology and archaeology because they can be used as stratigraphic time-markers. In this review, identification and dating methods of tephra are summarized. In addition, the characteristics of regional tephras in terrestrial deposits of the Korean Peninsula are elaborated, and geological applications and limitations of the regional tephra layers are also discussed. So far, AT, Ata, and Kb-Ks tephra layers from Kyushu, Japan have been found in Pleistocene paleosol, marine terrace deposits, and lacustrine deposits in Korea. Also, although not officially confirmed, Aso-4 tephra is likely to occur in terrestrial deposits. The regional tephra layers are vital for dating, especially with regard to sediments over 50 ka beyond the range of radiocarbon dating, and for dating of active faults. Furthermore, it can provide important information for preparing countermeasures against volcanic disasters. However, in order to use the tephra layer geologically, it must be confirmed whether it is a primary deposit based on sedimentological study.

• Journal of Ecology and Environment
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• v.46 no.1
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• pp.31-40
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• 2022

Background: Plant vegetation appears in heterogeneous and patchy forms in arid and semi-arid regions. In these regions, underneath the plant patches and the empty spaces between them are covered by biological soil crusts (moss, lichen, cyanobacteria, and fungi). Biological soil crusts lead to the formation and development of fertile islands in between vegetation patches via nitrogen and carbon fixation and the permeation of runoff water and nutrients in the soil. Results: The present study has investigated the association of biological soil crusts, the development of fertile islands, and the formation of plant patches in part of the Takht-e Soltan protected area, located in Khorasan Razavi Province, Iran. Three sites were randomly selected as the working units and differentiated based on their geomorphological characteristics to the alluvial fan, hillslope, and fluvial terrace landforms. Two-step systematic random sampling was conducted along a 100-meter transect using a 5 m² plot at a 0-5 cm depth in three repetitions. Fifteen samplings were carried out at each site with a total of 45 samples taken. The results showed that the difference in altitude has a significant relationship with species diversity and decreases with decreasing altitude. Results have revealed that the moisture content of the site, with biocrust has had a considerable increase compared to the other sites, helping to form vegetation patterns and fertile islands. Conclusions: The findings indicated that biological crusts had impacted the allocation of soil parameters. They affect the formation of plant patches by increasing the soil's organic carbon, nitrogen, moisture and nutrient content provide a suitable space for plant growth by increasing the soil fertility in the inter-patch space.

• Journal of the Korean Institute of Rural Architecture
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• v.24 no.2
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• pp.21-28
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• 2022

Focusing on the creation of a new han ok, especially a mid-rise hybrid-structured Han-ok, this study proposes a middle-rise (four-story) Han-ok on one and two lots located in Seoun-dong, the existing Han-ok intensive housing site in downtown Cheongju. 1) In terms of layout and function, according to the existing L-shaped Han-ok corresponding to the road and the direction, the parking lots and shops on the 1st floor, the business facility on the 2nd floor, the Han-ok on the 3rd and 4th floors are placed. There are yards, open roof yards, and semi-open Daecheong(大廳, main hall), which can be shared by residents. 2) In terms of structure and form, one or two floors (some 3 floors) are 5.4m square and 5.4×6.6m modules of the RC(Reinforced Concrete) group, and the upper floor reflects the 2.7m module, size and shape of the existing Han-ok. By extending the outer wall of the RC group in the lower floors (1st to 3rd floors) to the wooden exterior of the upper floors (2nd to 4th floors), it is attempted to avoid the awkward appearance of the RC group being exposed to wooden structures. And it is also attempted to reflect the wooden shape and design elements through the elevation elements such as horizontal windows, corner windows, picture frames, and vertical slits. 3) In environmental control and facilities, it is attempted to smooth the ventilation of the building by forming a vertical upward airflow from the dark space of the low floor to the positive of the upper floor. This doubles the effect through a vertical rise of cold air generated in a narrow alleyway, piloti parking lot, and the various voids. In addition to the Daecheong and Numaru(loft) of Han ok, the rooftop yard, the terrace, and the balcony, horizontal natural ventilation is generated through divided doors and transom windows.

• Journal of The Geomorphological Association of Korea
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• v.18 no.4
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• pp.213-221
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• 2011

The purpose of this study is to clarify the characteristics of forms and distributions of Gapyoungchon potholes. Different sizes of 153 potholes were distributed in the upper stream marginal area that was 30×25m, and over 70 percent among them were egg-shaped potholes. A development of joint in pothole was not important to make potholes in the stream but the mean size of potholes with joint was larger than without joint. Moreover, the schistosity structure of the bedrock was more important factor to develop potholes in this area. Finally, four cross sectional faces were found in this study area. From the reason, Gapyoungchon potholes are distributed on the rock terraces.

• Journal of The Geomorphological Association of Korea
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• v.28 no.3
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• pp.51-61
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• 2021

Following the previous study, we report a complementary dating data on the silty layers deposited in paleo-tidal conditions of the study area, Dangjeong-ri, Seocheon-gun and suggest coastal terrain development processes over the past 200,000 years. Based on the dating results, the silty layers distributed up to 25 m above mean sea level were deposited between 171 and 183 ka, and the gravel layer deposited in a fluvial environment of a paleo-Dangjeong stream was found to have formed between 78 and 83 ka. Considering relative altitudes of distribution, an uplift rate of the study area in the western coast is judged to be relatively 0.5~0.7 low to that of Pohang area in the eastern coast. Compared to Busan and Sacheon areas in the southern coast, it is assumed that an uplift rate of the study area shows a similar level with those during the late Quaternary.

• Journal of The Geomorphological Association of Korea
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• v.27 no.3
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• pp.41-51
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• 2020

This study tried to reveal incision rate distribution of streams on the northern part of the Sobaek Mountain Range with OSL age dating and geomorphic analysis, and factors influencing on the distribution were also discussed. With results from the previous studies, a total of 10 sites from 7 streams in the study area showed the rates ranging from 0.220 m/ka to 0.297 m/ka. Namhan-gang and Geum-cheon indicated the highest and lowest rates, respectively. Both sides in the northern section in the study area showed similar rates, while the western side in the middle section and the eastern side in the southern section showed higher rates than the other sides. Higher rates were also found from the eastern and northern sides where the Range runs N-S and E-W directions, respectively. Certain relationships with altitude and distance from the divide can be recognized from the rates and may be attributed to active incision with altitude and location of the uplift axis near the present divide. The rates on granite and sedimentary rock were higher than those on metamorphic rock, indicating that bedrock type is one of the important factors influencing on stream incision. Tectonic movement seemed to play some roles in the rates, because areas with lineaments showed lower rates. This study suggests that incision rate distribution of streams on the northern part of the Sobaek Mountain Range reflects various local geomorphic and geologic conditions.

• Journal of The Geomorphological Association of Korea
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• v.27 no.1
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• pp.33-45
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• 2020

A number of unconsolidated deposits, consisting of a layer of gravels and silt, are found in Dangjeong-ri, Seocheon-gun in the western coast. From below in the stratigraphic sequence, the gravel layer ranging up to a maximum thickness of about 2 meters is interpreted as being formed by fluvial processes of an old channel (Dangjeong S.), and the overlying silt or sandy silt layer of 2 to 3 thickness meters is assumed to be emerged paleo-tidal sediments which was deposited in low tidal-energy environments. As the results of rock surface IRSL datings, the depositional ages of gravels are confirmed as ca. 78,000 ~ 83,000 years BP, indicating that the layer was formed in response to a high-stand sea level of MIS 5a along the Dangjeongcheon estuary. It is presumed that the relative height of 4.5 meter between the altitude of the stream bed (9.5 m) and the altitude of the bedrock boundary in the gravel layer (14 m) indicates the uplift amount since deposition. Paleo-sedimentary environments and an altitude of paleo-shoreline in the study area will be discussed with additional age dating focused on the silt layer.

• Journal of the Korean Association of Geographic Information Studies
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• v.12 no.1
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• pp.64-72
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• 2009

The method to generate a digital elevation model(DEM) from contour lines causes a problem in which the low relief landform cannot be clearly presented due to the fact that it is significantly influenced by the expression of micro landform elements according to the interval of contours. Thus, this study attempts to develop a landcover burning method that recovers the micro relief landform of the DEM, which applies buffering and map algebra methods by inputting the elevation information to the landcover. In the recovering process of the micro landform, the DEM was recovered using the buffering method and elevation information through the map algebra for the landcover element for the micro landform among the primary DEM generation, making landcover map, and landcover elements. The recovering of the micro landform was applied based on stream landforms. The recovering of landforms using the buffering method was performed for the bar, which is a polygonal element, and wetland according to the properties of concave/convex through generating contours with a uniform interval in which the elevation information applied to the recovered landform. In the case of the linear elements, such as bank, road, waterway, and tributary, the landform can be recovered by using the elevation information through applying a map algebra function. Because the polygonal elements, such as stream channel, river terrace, and artificial objects (farmlands) are determined as a flat property, these are recovered by inputting constant elevation values. The results of this study were compared and analyzed for the degree of landform expression between the original DEM and the recovered DEM. In the results of the analysis, the DEM produced by using the conventional method showed few expressions in micro landform elements. The method developed in this study well described wetland, bar, landform around rivers, farmland, bank, river terrace, and artificial objects. It can be expected that the results of this study contribute to the classification and analysis of micro landforms, plain and the ecology and environment study that requires the recovering of micro landforms around streams and rivers.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.32 no.4
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• pp.132-142
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• 2014

This study is the first stage to identify distinctive characteristics of American Romantic Garden compared to English Romantic Garden. The purpose of the study is to identify characteristics of transitional garden in the early period of America by analyzing of Paca garden, Mount Vernon and Monticello when English Naturalistic Garden was firstly imported. The analysis studied historical background, people who designed garden, formal garden and characteristics of natural garden through reference. Also based on data through reference and field research, spatial configuration and garden factors of each site were analyzed. In spatial configuration, straight line and curve line, formal terrace and natural slope, visible axis and invisible axis, symetric and asymmetric, and perspective and oblique perspectives were used as analyzing factors. As a result of analysis, each garden showed different type from that of formal gardens from colony period, which is natural garden of asymmetric garden(English natural garden) coexisted. Paca garden which planned formal garden and natural garden in each space showed characteristics of each space, but in formal garden residential axis and garden axis does not coincide which shows it is out of formal garden type. Such phenomena and the fact that naturalistic garden coexist in the same garden shows that the formal garden type from early days in US is starting to change in different types. Mount Vernon garden, similar to Paca garden, was designed to have two different types of gardens in harmony rather than divide the space into different space and design it. It adapted serpent walkway but shows symmetric by central axis and considered formalistic plan through same materials. However through terrace in hills and spatial plan of oblique perspective, one could observe that naturalistic type was beginning to settle in US gardens. Through Monticello analysis, space was designed with major characteristics of naturalistic garden which is serpent walkway, ornamental farm, winding flower bed grove and bush and oblique perspective, and it completely duplicates characteristics of naturalistic garden which could not be found in gardens imported from UK.