• Journal of Korea Water Resources Association
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• v.54 no.12
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• pp.1339-1348
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• 2021

In accordance with the River Law, the basic river maintenance plan is established every 5-10 years with a considerable national budget for domestic rivers, and various river surveys such as the river section required for HEC-RAS simulation for flood level calculation are being conducted. However, river survey data are provided only in the form of a pdf report to the River Management Geographic Information System (RIMGIS), and the original data are distributedly owned by designers who performed the river maintenance plan in CAD format. It is a situation that the usability for other purposes is considerably lowered. In addition, when using surveyed CAD-type cross-sectional data for HEC-RAS, tools such as 'Dream' are used, but the reality is that time and cost are almost as close as manual work. In this study, RAUT (River Information Auto Upload Tool), a tool that can solve these problems, was developed. First, the RAUT tool attempted to automate the complicated steps of manually inputting CAD survey data and simulating the input data of the HEC-RAS one-dimensional model used in establishing the basic river plan in practice. Second, it is possible to directly read CAD survey data, which is river spatial information, and automatically upload it to the river spatial information DB based on the standard data model (ArcRiver), enabling the management of river survey data in the river maintenance plan at the national level. In other words, if RIMGIS uses a tool such as RAUT, it will be able to systematically manage national river survey data such as river section. The developed RAUT reads the river spatial information CAD data of the river maintenance master plan targeting the Jeju-do agar basin, builds it into a mySQL-based spatial DB, and automatically generates topographic data for HEC-RAS one-dimensional simulation from the built DB. A pilot process was implemented.

• Korean Journal of Agricultural and Forest Meteorology
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• v.11 no.4
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• pp.162-173
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• 2009

Information on the expected geographical shift of suitable zones for growing crops under future climate is a starting point of adaptation planning in agriculture and is attracting much concern from policy makers as well as researchers. Few practical schemes have been developed, however, because of the difficulty in implementing the site-selection concept at an analytical level. In this study, we suggest site-selection criteria for quality Fuji apple production and integrate geospatial data and information available in public domains (e.g., digital elevation model, digital soil maps, digital climate maps, and predictive models for agroclimate and fruit quality) to implement this concept on a GIS platform. Primary criterion for selecting sites suitable for Fuji apple production includes land cover, topography, and soil texture. When the primary criterion is satisfied, climatic conditions such as the length of frost free season, freezing risk during the overwintering period, and the late frost risk in spring are tested as the secondary criterion. Finally, the third criterion checks for fruit quality such as color and shape. Land attributes related to these factors in each criterion were implemented in ArcGIS environment as relevant raster layers for spatial analysis, and retrieval procedures were automated by writing programs compatible with ArcGIS. This scheme was applied to the A1B projected climates for South Korea in the future normal years (2011-2040, 2041-2070, and 2071-2100) as well as the current climate condition observed in 1971-2000 for selecting the sites suitable for quality Fuji apple production in each period. Results showed that this scheme can figure out the geographical shift of suitable zones at landscape scales as well as the latitudinal shift of northern limit for cultivation at national or regional scales.

• Journal of the Korean Association of Geographic Information Studies
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• v.26 no.1
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• pp.21-40
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• 2023

This study analyzed the cold air characteristics of the Nakdong Jeongmaek, which is advantageous for the formation of cold air that can flow into the city, in order to suggest the wind ventilation corridor plans, which have recently been increasing interest as a way to improve the urban thermal environment. In addition, based on the watershed analysis, specific cold-air watershed areas were established and management plans were suggested to expand the cold air function of the Nakdong Jeongmaek. As a result of the analysis of cold air in the Nakdong Jeongaek, cold air was strongly generated in the northern forest of the Jeongamek, and flowed into nearby cities along the valley topography. On average, the speed of cold air was high in cities located to the east of the Jeongmaek, while the height of cold air layer was high in cities located to the west. By synthesizing these cold air characteristics and watershed analysis results, the cold-air watershed area was classified into 8 zones, And the plans were proposed to preserve and strengthen the temperature reduction of the Jeongmaek by designating the zones as 'Conservation area of Cold-air', 'Management area of Cold-air', and 'Intensive management area of Cold-air'. In addition, in order to verify the temperature reduction of cold air, the effect of night temperature reduction effect was compared with the cold air analysis using weather observation data. As a result, the temperature reduction of cold air was confirmed because the night temperature reduction was large at the observation station with strong cold air characteristics. This study is expected to be used as basic data in establishing a systematic preservation and management plan to expand the cold air function of the Nakdong Jeongmaek.

• (The)Study of the Eastern Classic
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• no.49
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• pp.73-107
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• 2012

Yeoheon Jang Hyeongwang(1554-1637), one of the greatest Mid-Joseon Confucianists did systematic studies on universe and nature. It can be considered that he inherited the academic tradition of Cho Sik (曺植) and Jeong Gu(鄭逑) and followed their steps of fengshui (風水) and compilation of geographical records. His living and thought and deserve researching with regard to geographical studies. This paper attempts to analyze Yeoheon's recognition of geography in general. In other words, I shall prove that his view of geography is Neo-Confucian. At the same time, I shall discuss how he named people's residence, how he understanded the Joseon territory, what he thought about fengshui, and what significance the complication of geographical records by his disciples had. Yeoheon considered that land is composed of water, fire, earth, and rock, and understanded the land according to the theory of Zhouyi (周易). He analyzed geographic environments by the system of Zhouyi. His study of geography is basically intended for practical use, and as a result is necessary for people to choose where to live and where to cultivate. In his opinion, it is essential to divide the land of the Joseon by means of geographical differences in order to help people to find a better place to live. We can see his Confucian view from the fact that he placed a greater emphasis on human beings over nature. Therefore, the practical use for humans is the first priority in his study of geography. Meanwhile, he considered nature itself as only the object of study. He realized the vitality of life by making a close observation of nature and attained the mind of the Heaven and Earth in a detached way. He, as a follower of Neo-Confucianism, enjoyed the land by feeling comfortable with his present status and by being satisfied with himself. He put his Confucian view of universe and world into practice in his life. As a part of his efforts, he named his residence and surrounding natural environments with the polar star and 28 stars, and accordingly they are reconstructed in a system of universe. The Confucian tradition of dongcheon gugok (洞天九曲) starting with Zhu Xi's administration of wuyi jiugu (武夷九曲) was widely prevalent during the Joseon period, but Yeoheon's system of organizing places is original. His sense of naming places reflects his ideas of following his predecessors, comparing natural objects to human emotions, and desiring to live in retirement. Yeoheon understanded the Joseon territory with comparison of the Chinese land. He expressed his knowledge in the form of changing geographical features of a district, appreciating natural beauty, locating towns, and being familiar with a region, and proposing his own climatology and view of the reality. His recognition of the Joseon territory resolves itself into the following several points. He regarded the Joseon territory as one organism, and considered the territory to be composed of ki (氣) as Neo-Confucianists usually do. In addition, he understanded not only natural environments but also towns from a perspective of the fengshui and adopted a comparative methodology in dividing regions. He also applied climatology to analyze persons and customs. He employed the methodology of fengshui from the comprehensive theory of the Yijing. It is because he was influenced by Cho Sik and Jeng Gu. Yeoheon chose dwelling places for people, or gave advice on several places of his hometown relying on his knowledge of fengshui. When it comes to his theory of fengshui, he agreed with the theory of topography with regards to the fengshui of tombs, but criticized the custom of delaying funerals in order to turn fortune in one's favor. In addition, he accepted that it is necessary to complement a town by creating forests around it. We need to pay attention to the fact that Yeoheon's disciples complied several geographical records. It proves that they inherited the tradition of "valuing practical use and governing on behalf of the people" from Cho Sik and Jeong Gu. Yeoheon put a great emphasis on geographical records and encouraged his disciples to compile them. In other words, he emphasized that they, as administrator or intellectual, need to be erudite in the history and custom of a region where they have lived, and have to establish a standard to encourage or warn people in the region while considering the geographical records. His opinion functioned as a guideline for his successors to compile geographical records later. This paper only analyzed several facts with regard to Yeoheon's knowledge of geography and an academic tradition concerning the study of geography. In the future, I shall discuss how his predecessors and successors understanded geography and how the tradition of compiling geographical records was transferred and developed between them. I believe that this study will contribute to establishing the history of geography, which the Joseon Confucianists researched for a long time but we have not paid an enough attention to until now.

• Journal of the Korean Association of Geographic Information Studies
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• v.22 no.2
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• pp.152-171
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• 2019

In this study, we analyzed the characteristics of the cold air generated in Hannamgeumbuk and Geumbuk-Jeongmaek and proposed their management strategies. We also suggested management strategies after analyzing detailed cold airflows for Cheongju located Hannamgeumbuk-Jeongmaek and we compared the degree of nighttime temperature reduction of the Jeongmaek by using data obtained from observatories located on Cheongju. We used KALM(Kaltluftabflussmodell), a cold air simulation model developed in Germanay and identified both cold airflows and altitude of cold air layers generated during 360minutes at night. As a result, the cold airflow generated in the Jeongmaek became strong and the cold air was appeared clearly in the western part of the Hannamgeumbuk-Jeongamek and in the northern part of the Geumbuk-Jeongmaek. The average velocity of cold airflow was recorded at 0.45m/s, and the maximum speed of cold airflow was recorded at 2.70m/s. The average height of the cold air layer was 104.27m/s and the maximum thickness was 255.0m. The average velocity of cold airflows in Cheongju was 0.51m/s and the average height of cold air layer was 48.87m high. The highest degree of nighttime temperature reduction appeared in the Cheongnamdae observatory($-3.8^{\circ}C$), where the altitude of the cold air layer is high. The results showed that cooling effect of Jeongmaek actually affected the temperature reduction during nighttime. Based on the results, we designated the main mountain area of the Jeongmaek with active cold air generation as "cold air conservation areas" and proposed the current forest and topography conservation. We also proposed to designate areas that facilitate the cold airflows as "cold air management areas" and to complement the function of Jeongmaek. This study could support the establishment of systematic management plans of the Jeongmaek. In addition, it is expected that the results can be applied as basic data for ventilation paths of Cheongju.

• Journal of the Korean Association of Geographic Information Studies
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• v.24 no.4
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• pp.99-112
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• 2021

This study was performed to predict spatial change of future forestland area in South Korea at regional level for supporting forest-related plans established by local governments. In the study, land use was classified to three types which are forestland, agricultural land, and urban and other lands. A logistic regression model was developed using transitional interaction between each land use type and topographical factors, land use restriction factors, socioeconomic indices, and development infrastructures. In this model, change probability from a target land use type to other land use types was estimated using raster dataset(30m×30m) for each variable. With priority order map based on the probability of land use change, the total annual amount of land use change was allocated to the cells in the order of the highest transition potential for the spatial analysis. In results, it was found that slope degree and slope standard value by the local government were the main factors affecting the probability of change from forestland to urban and other land. Also, forestland was more likely to change to urban and other land in the conditions of a more gentle slope, lower slope criterion allowed to developed, and higher land price and population density. Consequently, it was predicted that forestland area would decrease by 2027 due to the change from forestland to urban and others, especially in metropolitan and major cities, and that forestland area would increase between 2028 and 2050 in the most local provincial cities except Seoul, Gyeonggi-do, and Jeju Island due to locality extinction with decline in population. Thus, local government is required to set an adequate forestland use criterion for balanced development, reasonable use and conservation, and to establish the regional forest strategies and policies considering the future land use change trends.

• Economic and Environmental Geology
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• v.38 no.6 s.175
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• pp.607-622
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• 2005

This study was carried out in order to evaluate where the soil loss was mainly occurred, .and to verify how riverbed sediments in the tributaries of the Seomjin River were related to their source rocks distributed in Sunchang area. The study area including the Seomjin River with 4 tributaries of Kyeongcheon, Okgwacheon, Changjeong-cheon and Ipcheon was divided into 10 watershed. The RUSLE (Revised Universal Soil Loss Equation) was estimated for all the grids (10 m cells) in the corresponding watershed. The amount of soil loss per unit area was calculated as follows: dry fold (53,140.94 tons/ha/year), orchard (25,063.38 tons/ha/year), paddy field (6,506.7 tons/ha/year) and Idlest (6,074.36 tons/ha/year). The differences of soil loss per unit area appear to be depends on areas described earlier. Soil erosion hazard zones were generally distributed within dry fields. Several thematic maps such as land use maps, topographical maps and soil maps were used as a data to generate the RUSLE factors. The amount of soil loss, computed by using the RUSLE, showed that soil loss mainly occurred at the regions where possible source rocks were distributed along the stream. Based on the this study on soil loss and soil erosion hazard zone together with chondrite-normalized REE patterns that were previously analyzed in same study area, a closed relationship between riverbed sediments and possible source rocks is formed. Especially in the Okgwacheon that are widely distributed by various rocks, chondrite-normalized REE pattern derived from the riverbed sediments, source rock and soil is expected to have a closed relationship with the distribution of soil loss.

• Korean Journal of Ecology and Environment
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• v.51 no.2
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• pp.149-159
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• 2018

Twenty-nine wetlands (20 river type and 9 lake type wetlands) in Gyeongsangnam-do were investigated to understand the characteristics of fish assemblages by the wetland type and to suggest management strategies. As a result, $10.3{\pm}4.8$ species were collected from river type wetlands on average (${\pm}SD$) and $9.1{\pm}4.1$ species from lake type wetlands. Thus, there was no significant difference in the number of species between them (Mann-Whitney U test, P>0.05). However, the species that constitute the fish assemblage showed statistically significant differences between the two wetland types (PERMANOVA, Pseudo-F=2.9555, P=0.007). Furthermore, the species that contribute the most to each type of fish assemblage were Zacco koreanus (river type, 28.51%) and Lepomis macrochirus (lake type, 23.21%), respectively (SIMPER). The results of the NMDS analysis using the fish assemblage by place classified the species into three groups (river type, lake type, and others). The current wetland management is only focused on endangered species, but this study shows a difference in fish assemblage by wetland type. Therefore, a management system based information on endemic species, exotic species and major contribution species should be provided. Furthermore, the classification of some types of wetlands based on the present topography was found to be ambiguous, and wetland classification using living creatures can be used as a complementary method. This study has limitations because only two types of wetlands were analyzed. Therefore, a detailed management method that can represent every type of wetland should be prepared through the research of all types of wetlands in the future.

• Korean Journal of Agricultural and Forest Meteorology
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• v.3 no.4
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• pp.199-205
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• 2001

This study was conducted to figure out temperature profiles of a partially developed paddy rice canopy, which are necessary to run plant disease forecasting models. Air temperature over and within the developing rice canopy was monitored from one month after transplanting (June 29) to just before heading (August 24) in 1999 and 2001. During the study period, the temporal march of the within-canopy profile was analyzed and an empirical formula was developed for simulating the profile. A partially developed rice canopy temperature seemed to be controlled mainly by the ambient temperature above the canopy and the water temperature beneath the canopy, and to some extent by the solar altitude, resulting in alternating isothermal and inversion structures. On sunny days, air temperature at the height of maximum leafages was increased at the same rate as the ambient temperature above the canopy after sunrise. Below the height, the temperature increase was delayed until the solar noon. Air temperature near the water surface varied much less than those of the outer- and the upper-canopy, which kept increasing by the time of daily maximum temperature observed at the nearby synoptic station. After sunset, cooling rate is much less at the lower canopy, resulting in an isothermal profile at around the midnight. A fairly consistent drop in temperature at rice paddies compared with the nearby synoptic weather stations across geographic areas and time of day was found. According to this result, a cooling by 0.6 to 1.2$^{\circ}C$ is expected over paddy rice fields compared with the officially reported temperature during the summer months. An empirical equation for simulating the temperature profile was formulated from the field observations. Given the temperature estimates at 150 cm above the canopy and the maximum deviation at the lowest layer, air temperature at any height within the canopy can be predicted by this equation. As an application, temperature surfaces at several heights within rice fields were produced over the southwestern plains in Korea at a 1 km by 1km grid spacing, where rice paddies were identified by a satellite image analysis. The outer canopy temperature was prepared by a lapse rate corrected spatial interpolation of the synoptic temperature observations combined with the hourly cooling rate over the rice paddies.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.34 no.4
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• pp.57-65
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• 2016

Maeul-soop(Village forest) is a key element of Korean traditional village landscape historically and culturally. However, a number of Maeul-soops have been lost or declined due to various influences since the modern age. For this Maeul-soop that has a variety of conservation values including historical, cultural and ecological ones, attention and efforts for a systematic conservation and restoration of Maeul-soop are needed. The purpose of the present study is to provide information on ecological restoration and sustainable use and management of Maeul-soops based on component plant species, habitat and location characteristics of 499 Maeul-soops spread throughout Korea. Major six categories of threat factors to Maeul-soop ecosystem were identified and the influence of each factor was evaluated. For the evaluation of weight by threat factors for the influence on the vulnerability of Maeul-soop ecosystem, more three-dimensional analysis was conducted using Analytic Hierarchy Process (AHP) analysis method. In the results of evaluation using AHP analysis method, reduction of area, among six categories, was spotted as the biggest threat to existence of Maeul-soops. Next, changes in topography and soil environment were considered as a threat factor of qualitative changes in Maeul-soop ecosystem. Influence of vegetation structure and its qualitative changes on the loss or decline of Masul-soop was evaluated to be lower than that of changes in habitat. Based on weight of each factor, the figures were converted with 100 points being the highest score and the evaluation of vulnerability of Maeul-soop was conducted with the converted figures. In the result of evaluation of vulnerability of Maeul-soops, grade III showed the highest frequency and a normal distribution was formed from low grade to high grade. 38 Maeul-soops were evaluated as grade I which showed high naturality and 10 Maeul-soops were evaluated as grade V as their maintenance was threatened. Also in the results of evaluation of vulnerability of each Maeul-soop, restoration of Maeul-soop's own area was found as top priority to guarantee the sustainability of Maeul-soops. It was confirmed that there was a need to prepare a national level ecological response strategy for each vulnerability factor of Maeul-soop, which was important national ecological resources.