• Journal of the Korean association of regional geographers
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• v.3 no.1
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• pp.51-62
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• 1997

In various places of drainage basins of major rivers in South Korea are distributed intermontane basins. Basin floor covered with fluvial deposits carried from the surrounding mountane area becomes alluvial plain. Its productivity is comparatively higher than anywhere else. Thus basin is a local administrative, economic, and cultural core area. Intermontane basin consists of backward mountane area, gentle hills, and alluvial lowland. The purpose of this paper is to elucidate the morpogenetic processes and development age of Angae Basin located in the sedimentary rock region. Hills with the height of a.s.l. $80{\sim}100m$ distributed in Angae Basin are residual landforms, which are the remnants of dissection of the etchplain that results from the denudation of bedrock deeply weathered along tectolineaments under the warm and moist climate, and reflect lithological differentiation of bedrock. Those hills have been comparatively higher ridges since the initial stage of the original etchplain, and they have been immune from fluvial processes. The etchplain appeared as $80{\sim}100m$ hills. the high terrace distributed in upstream reach of Nakdong River drainage basin and the old meander-cut at Seoburi in Wicheon drainage basin, are formed at the same stage when riverbed of Wicheon Stream functioned as a local base level according as the fluvial system of Wichoen arrived at dynamic equilibrium.

• Journal of the Korean Geographical Society
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• v.40 no.6 s.111
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• pp.716-729
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• 2005

In the Yeongpyeong River, one of the branches of Hantan River, there 4 fluvial terraces are identified. During the Quaternary, lava flow from Hantan River had gone 4.5km into upstream Part of the Yeongpyeong River and damed its entrance, and resultantly its lower basin had become a lava-damed paleolake. This study deals with fluvial terrace surface classification, stratigraphic analysis, deposits analysis, and OSL age dating in from Gungpyeongri to Seongdongri in lower reach of Yeongpyeong River, in order to identify Seomorphological Process of the terrace landforms relating to duration of lava-damed paleolake. Terrace surface T4, named Baekeuiri Formation, has been located under Jeongok lava layer to indicate pre-lava river bed. Terrace surfaces T3 and T2 are supposed to be formed during paleolake time, based on $3{\~}4m$ thick sand deposits including pebble and cobble layers, and clay and silt layers intersected with sand ones in nearly horizontal bedding. Terrace T1 is estimated to be formed as post-lake fluvial terrace after dissection of lava dam, based on the more fresh phase of deposits and very low height from present riverbed. The results of the OSL age dating for the T3 deposit layers indicate approximately $33{\~}40ka$, and still lake phase at that time.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.10 no.3
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• pp.139-144
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• 2005

To investigate the long-term variation of water qualities, we have daily monitored physio-chemical characteristics of surface water in the Geum River estuary from June 1996 to April 2004. We found that the water qualities were determined by three dominant factors : 1. fluvial input from Geum River ($28.3\%$), 2. chemical processes such as nitrification and phosphate addition originated from sediment resuspension and domestic sew- age input ($18.6\%$), 3. biological processes such as nutrient consumption by primary producers ($13.5\%$). The factor 1 (fluvial input) effectively affected the water quality of the estuary particularly during the normal or low river discharge. The factor 2 (chemical processes) and the factor 3 (biological processes) showed distinct seasonal differences due to their relative strengths of biological activities. The factor 3 was a governing parameter during the period of spring algal bloom in 2004. For the spring period, an empirical equation derived from the multi-regression analyses showed that the in-situ chlorophyll-a distributions in the estuarine water were successfully simulated by the phosphate concentrations and N/P ratios. Therefore we suggest that phosphate functions as a limiting factor for the primary productivity in the Geum River estuary for the dry season, especially during spring.

• Asian review of World Histories
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• v.4 no.1
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• pp.35-81
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• 2016

The objective of this essay is to propose a cultural history of cosmography and cartography from the thirteenth to the sixteenth centuries. It focuses on some of the processes that characterized these fields of knowledge, using mainly western European sources. First, it elucidates the meaning that the term cosmography held during the period under consideration, and the scientific status that this composite field of knowledge enjoyed, pointing to the main processes that structured cosmography between the thirteenth century and the sixteenth century. I then move on to expound the circulation of cosmographic knowledge among Portugal, Venice and Lisbon in the fourteenth and fifteenth centuries. This analysis will show how cartography and cosmography were produced at the interface of articulated commercial, diplomatic and scholarly networks; finally, the last part of the essay focuses on the specific and quite distinctive use of cosmography in fifteenth-century European culture: the representation of "geo-political" projects on the world through the reformulation of the very concepts of sea and maritime networks. This last topic will be developed through the study of Fra Mauro's mid-fifteenth-century visionary project about changing the world connectivity through the linking of several maritime and fluvial networks in the Indian Ocean, Central Asia, and the Mediterranean Sea basin, involving the circumnavigation of Africa. This unprecedented project was based on a variety of sources accumulated in the Mediterranean Sea basin as well as in Asia and in the Indian Ocean over the course of several centuries.

• Journal of Environmental Impact Assessment
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• v.19 no.5
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• pp.511-525
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• 2010

Understanding of the hydraulics of flow over vegetation is very important to support the management of fluvial processes. The objective of this study is to assess the effects of hydraulic influence by tree planting in a compound channel with vegetated floodplain. This study analyzes the influence of tree planting on hydraulic features in Young-river in Munkyung city using HEC-RAS and RMA-2 model. The study results showed that there is a rise in water surface elevation and decrease in velocity near vegetated area. It is also ascertained that only negligible effects was seen within the feasible range of freeboard for the existing levees. However, as hydraulic features can vary depending on the aspect of flood inundation during each flood period, it is necessary to accumulate data through continuous data collecting.

• Ecology and Resilient Infrastructure
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• v.6 no.2
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• pp.89-100
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• 2019

We've reviewed existing studies on the interactions among vegetation, hydrology, and geomorphology in the stream corridors, adding one more factor of vegetation in the traditional area of hydro-geomorphology. Understanding of the interactions among those three factors is important not only academically but also practically since it is related intimately to the restoration of river corridor as well as management itself. Studies of this area started from field investigations in the latter part of the 20th century and focused on the flume experiments and then computer modelling in the 1990s and 2000s. Now, it has turned again to the field investigations of specific phenomena of the vegetative-hydrologic-geomorphologic interactions in detailed micro scales. Relevant studies in Korea, however, seem to be uncommon and far behind the international status quo in spite that practically important issues related directly to this topic have been emerged. In this study, we propose, based on the extensive literature review and authors' own knowledge and experiences, a conceptual diagram expressing the interactions among vegetation, flow (water), sediment, and geomorphology. Existing relevant studies in Korea since the 1990s are classified according to the categorization in the proposed diagrams and then briefly reviewed. Finally, considering the practical issues of riparian vegetation that have emerged recently in Korea, we propose areas of investigation needed in near future such as, among others, long-term and systematic field investigations and monitoring at multiple river corridors having different attributes on vegetative-hydrologic-geomorphologic interactions, including vegetative dynamics for succession.

• Journal of The Geomorphological Association of Korea
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• v.19 no.4
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• pp.157-168
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• 2012

The Eonyang section is located at the confluent area of Samdong River to Taehwa River in Sinhwa-ri, Samnam-myeon, Ulju-gun, Ulsan-si, Korea. Physical analyses such as the OSL age dating, magnetic susceptibility and grain size analysis were performed. Coarse grains in the upper section were deposited by the aeolian processes from the local sources and the grains in the lower section by the fluvial processes. The Eonyang section shows the large differences such as the irregularity in the variations of magnetic susceptibility, large deviations in the Y values and very poor sorting values from the loess sediments in Bongdong, Geochang and Daecheon in Korea. These characteristics in the Eonyang section suggest the multi-source areas such as the Chinese Loess Plateau and nearby floodplain or the influences by the other processes. The loess sediments of Eonyang section were formed during the period from the late MIS 3 to MIS 2.

• Korean Journal of Agricultural Science
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• v.38 no.2
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• pp.315-324
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• 2011

Riparian vegetation distribution patterns and diversity relative to various fluvial geomorphic channel patterns, stream bank stabilization methods, and stream flow processes are described and interpreted for selected nature-friendly small stream bank protection of Goesan, central Korea. Idong Stream Pilot Project, which began in May 2003 and finished in December 2003, was selected to develop effective methods which was nature-friendly stream bank protection. The project aim to maintain or increase stream bank stabilization ecosystem goods and services while protecting downstream and stream bank ecosystem. A number of protecting methods which were a Flight of fieldstone, Vegetation block, Green river block, Stone net, Green environment block, Eco friendly cobble, Vegetation mat and Geo-green cell and Firefly block were applied on the bank of Idong stream. The stream sites have been monitored about vegetation conditions each method in 2007. We selected six points to separately investigate in left and right bank. The main purpose of this study was to find out suitable methods and to improve stream restoration techniques for ecosystem. On the stream bank, H environment block method (9.7) was the highest average of vegetation coverage and Firefly block method (3.87) was the lowest average in applied methods.

• Proceedings of the Korea Water Resources Association Conference
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• 2009.05a
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• pp.2078-2082
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• 2009

Riparian vegetation distribution patterns and diversity relative to various fluvial geomorphic channel patterns, stream bank stabilization methods, and stream flow processes are described and interpreted for selected stream of Goesan, Central Korea. Idong Stream Pilot Project, which began in May 2003 and finished in December 2003, was selected to develop effective methods. The project aim to maintain or increase stream bank stabilization ecosystem goods and services while protecting downstream and stream bank ecosystem. A number of protecting methods which are a Flight of fieldstone, Vegetation block, Green river block, Stone net, Green environment block, Eco friendly cobble, Vegetation mat and Geo green cell and Firefly block were applied on the bank of Idong stream. The stream sites have been monitored about flora conditions each method in 2007. We selected 12 points for summer seasons to separately investigate in left bank, right bank and river bed. The main purpose of this study was to find out suitable methods and to improve stream restoration techniques for ecosystem. On the stream bank, Eco friendly cobble method(9.57) was the highest average of vegetation cover and Firefly block method(3.87) was the lowest average in applied methods.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.9 no.4
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• pp.153-163
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• 2004

In order to estimate the nutrient flux of the Seomjin River into the coastal waters of South Sea, and to understand the estuarine reactions during mixing between river water and seawater, we collected surface water along the salinity gradient in the Seomjin River estuary from Mar. 1999 to Apr. 2001. We found that nitrate and silicate were delivered by fluvial input, while phosphate was, supplied from disposed wastes in the Gwangyang Bay. Mean annual flux of dissolved inorganic nitrogen (DIN), phosphate and silicate into the Gwangyang Bay was estimated 10.9 molesㆍsec$^{-1}$(4,820 tonnesㆍyr$^{-1}$), 0.07 molesㆍsec$^{-1}$(68 tonnesㆍyr$^{-1}$), 13.3 molesㆍsec$^{-1}$(11,747 tonnesㆍy$^{-1}$), respectively. An evident removal of phosphate, silicate and ammonium at the mid-salinity zone during the dry season was attributed to the active uptake of phytoplankton, and consequently nutrient flux into the Gwangyang Bay was low. Whereas, during the flood season in summer, conservative or additional distribution of the nutrients was observed in the estuary. As a rsult nutrient flux into the Gwangyang Bay was maintained high. High concentrations of chlorophyll a and the active removal of nutrient during the dry season at the mid-salinity zone suggest that nutrient distribution in the Seomjin River estuary was mainly controlled by biological processes and nutrient fluxes into the Gwangyang Bay might be significantly modified of by the primary production.