• Korean Journal of Ecology and Environment
• /
• v.41 no.3
• /
• pp.283-293
• /
• 2008

The objectives of the study were firstly to provide fundamental data for establishment of total maximum daily load (TMDL) management in Ulsan City, and secondly to make practical application of stream health assessment with tolerance range by each species when physiochemical and fish investigations were carried out together. A total of 44 sites in Taehwa River, Hoiya River, Dong Stream, and Cheongryang Stream were selected to monitor water qualities seasonally and fish investigation was performed in August 2006. Among the parameters of water quality, biological oxygen demand (BOD) and dissolved oxygen (DO) related to respiration, total nitrogen (T-N) and total phosphorus (T-P) related to nutrient and eutrophication, and total suspended solids (TSS) and $NH_4$-N were compared with vertical box plot by 8 dominant species. According to the fish investigation, 12 families 33 species were found including endangered species (Pungitius kaibarae) and introduced species (Lepomis macrochirus, Micropterus salmoides), and appearance rate of Korean endemic species was greater in Taehwa River (29.2%) than others. As the results of tolerance range by species, Zacco koreanus, Rhynchocypris oxycephalus, Iksookimia longicorpa, and Squalidus gracilis majimae had limited low range by water quality parameters indicating preference of good water quality. Whereas, Carassius auratus and Pseudorasbora parva were found downstream and urban-streams which were exposed from frequent inflow of pollutants. It concludes that the results help distinguishing sensitive, intermediate, and tolerant species when we evaluate stream health assessment with fish, and further making practical application for conservation and restoration of aquatic ecosystem.

• Ecology and Resilient Infrastructure
• /
• v.4 no.2
• /
• pp.97-104
• /
• 2017

For the restoration of lateral connectivity between channel and floodplain, it is important to find the former floodplain and to characterize its land use in streams which were channelized by the levee construction for the flood protection. The aim of this study is to map the former floodplains and to assess its land use pattern in the Cheongmi-cheon Stream, Korea. The former floodplains were explored by being overlapped on a digital elevation model (DEM), digital topographic map and design flood level using a geographical information system (GIS) in the Cheongmi-cheon Stream basin. The land use of the identified former floodplains was classified by land-use map. The total number of the former floodplains was 104 and their total area was $11.9km^2$ in the Cheongmi-cheon Stream. The land use pattern of the former floodplains was mostly farmland (87.1%). The former floodplains were usually surrounded by mountain forest in the downstream of the Cheongmi-cheon Stream. These former floodplains are probably suitable for restoration of lateral connectivity because of lower ratio of urban area but higher ratio of farmland. The results of delineation and land use analysis of the former floodplain can be used as a baseline data for planning stream restoration in the Cheongmi-cheon Stream.

• Korean Journal of Ecology and Environment
• /
• v.40 no.2
• /
• pp.303-317
• /
• 2007

The fish community of small freshwater ecosystems gets easily disturbed by direct or indirect human induced disturbances during the period of urbanization. Urbanization is one of factors that generate changes in stream and influences fish fauna in developed countries. This study was conducted in Busan Metropolitan City from 2001 to 2004. In order to investigate the fish community, the city was divided into 3 parts, eastern, central and western. A total of 3,206 individuals of 46 species from 19 families were collected from 55 sites. The dominant species was Rhynchocypris oxycephalus, whereas Zacco temminckii was the subdominant species. Cluster analysis was conducted using primary freshwater fish species collected from each stream. As a result of the analysis, study sites were well differentiated into 3 parts. Two species of Z. temminckii and R. oxycephalus represented the upper part of the stream and Carassius cuvieri, Acheilognathus rhombeus, Hemiculter eigenmanni and Micropterus salmoides represented the middle and lower parts of the stream. When compared with previous studies, fish community of the eastern part of the Busan city where urbanization is in progress, showed similar patterns to the central part. At the time of the habitat restoration of fish fauna in stream, appropriate selection of fish species should be made through analysis of stream character and biogeographic distribution of fish, and long-term monitoring is also needed for sustaining the management of fish fauna.

• Journal of Korea Water Resources Association
• /
• v.41 no.11
• /
• pp.1107-1121
• /
• 2008

The simple equation of GIUH are frequently used in many researches instead of the derived equation of GIUH. However it is still unknown whether the simple equation of GIUH is adaptable for estimating IUHs for basins with various geomorphologic conditions. To verify the applicability of the simple equation of GIUH, in this research, four basins which were Bangrim, Sanganmi, Museong, and Byeongcheon were selected and each basin was assumed as the third and fourth stream order basin according to variable resolutions. After than, IUHs were estimated using the derived and simple equations of GIUH. Eight to sixteen hydrographs were estimated from the each IUH, compared with observed graphs. In case of that the basin is assumed as a third order stream, the derived equation underestimated the peak flows while the simple equation overestimated them. When the basin is assumed as a fourth order stream, the simple equation generally overestimated the peak flows whereas the derived equation produced peak flows good agreement with the observed peak flow. Moreover, the simple equation showed various deviations in accuracy whereas the derived equation produced stable results. Based on the fact found from this research, it can be concluded that the derived equation of GIUH brings better results than the simple equation of GIUH to estimate IUHs for ungauged basins.

• Journal of the Korean Institute of Traditional Landscape Architecture
• /
• v.32 no.1
• /
• pp.74-82
• /
• 2014

The purposes of this study is to investigate spatial structure characteristics of earthen walled fortresses based on topography, which are locational and Plane morphology, Cross sections of earthworks. Target areas of this study are 37 earthen walled fortresses which are designated as cultural properties. This study is conducted with methodologies of literature review, field investigation, investigation on topography materials and relation analyses of topography&spatial structure. The results from study on spatial structure of earthen walled fortresses are as follows. First, Earthen walled fortresses on flat topography were adjacent to water systems like rivers or streams. Plane morphology showed regular shapes. The cross section morphology presented trapezoid the most with earthworks of which outer and inner walls were built. Second, More than 70% of earthen walled fortresses on hilly topography had water system within close range of approximately 1.5km. Plane morphology was mainly with more than 73% of irregular types. Cross sections of earthworks were of morphology with more than 86% of bordered type and another type leaning against existing topography like mountains. Third, 59% of earthen walled fortresses in mountain areas had water system within their close range, which indicated that they depended on external water system less than those with hilly topography. Plane morphology was mainly with more than 67% of irregular types. Cross sections of earthworks were of monoslope method with more than 94% of bordered type and another type leaning against mountains.

• Journal of Korean Society on Water Environment
• /
• v.36 no.2
• /
• pp.125-136
• /
• 2020

In this study, we identified the major pollution-zones of the mainstream and its tributaries of Gongneung stream and investigated their pollution sources based on water quality, flowrate and pollution-load data of the stream having the characteristics of the urban-rural complex to examine the effect of the tributaries on the water quality changes in the mainstream. The water quality and flowrate data were collected for 10 months (2018 ~ 2019) at 3 points of mainstream and ten tributaries. Water quality index (WQI), load duration curve (LDC), discharge load density (DLD)and delivery ratios for each tributary were obtained so as to investigate the pollution characteristics and some of the information visualized on GIS. The main pollution-zone in the Gongneung stream was in the middle and lower streams, and the tributaries that may affect the pollution of the area were JS, JY, SL and SM. JS and SL had low WQI levels (34.7/37.5) and DLD (kg/d/㎢) of BOD and T-P were relatively high in JY (99.2/6.00) and SL (60.0/2.07). BOD and T-P delivery ratios in JS were high (0.94/0.83), suggesting that JS had significant influence on the water quality of the main pollution-zone in the Gongneung stream. Meanwhile, SM having a high T-P delivery ratio (0.97) was found to be more affected by the non-point source due to the higher LDC excess rate (%) in the low flow compared to high flow. This study provides basic data on the water quality and pollution characteristics of the Gongneung stream, and the analysis results are expected to be used as examples for identifying the main pollution-zone and tributaries of stream and their pollution sources.

• Journal of the Korean Institute of Landscape Architecture
• /
• v.38 no.4
• /
• pp.96-105
• /
• 2010

The purpose of this study is to offer raw data on managing naturalized plants and the ecological characteristics of urban streams by researching the naturalized plants distributed in Naedong Stream, Changwon-si. The results are as follows. The numbers of naturalized plants were summarized as 45 taxa: 18 families, 38 genera, 43 species and 2 varieties. There were 3 taxa of invasive alien plants: Rumex acetocella, Ambrosia artemisiifolia var. elatior and Sicyos angulaus. In an analysis of life forms, there were 2 taxa of megaphanerophytes, 1 taxa of nanophanerophytes, 3 taxa of chamaiphytes, 7 taxa of hemicryptophytes, 1 taxa of geophytes and 31 taxa of therophytes. The urbanized and naturalized indices were 16.6% and 25.1%, respectively. The results of an analysis by vertical structures showed that naturalized plants included 30 taxa upstream, 42 taxa midstream and 32 taxa downstream. For the urbanized index, upstream was 11.1%, 15.5% in midstream and 11.8% in downstream. For the naturalized index, upstream was 21.7%, 33.3% in midstream and 37.2% in downstream. An analysis of crossing structures showed at taxa of 39 naturalized plants on bank. 30 taxa along the riverside and 7 in the water. For the urbanized index, banks were 14.4%, riverside 11.1% and waterside 2.6% while the naturalized index included 30.5% on the banks, 30.6% along the riverside and 20.0% in the water. As regards the management of naturalized plants, because Remex acetocella, Ambrosia artemisiifolia var. elatior and Sicyos angulaus have a negative impact on the ecosystem, they need to be efficiently controlled.

• Journal of Wetlands Research
• /
• v.16 no.4
• /
• pp.371-378
• /
• 2014

The subject of this study is the Gongchon-cheon which is one of the largest streams in Incheon and is closely related to lives of citizen. Comparative analysis is made on the changes of the environment and the ecological condition of Gongchon-cheon after the stream naturalization construction which is completed in July 2009. From the results of the survey, 32 species in 2004, 22 species in 2009 and 46 species in 2010 have been recorded. The number of the species decreased from 2004 to 2009 due to the disturbance of the river environment, and it increased in a short time from 2009 to 2010 because of the recovery of the environment. It demonstrates the stream naturalization construction providing enough environments (dikes and rapids) for the benthic macro invertebrates. The result of the present study is similar with the river's biology index, ESB index, and KSI index, and also it is similar with the pattern of the appearance, which illustrates that the species decreased during the naturalization construction, and increased after the stabilization since the finish of the naturalization construction, and it has been confirmed that the naturalization construction provides the better environment for the inhabitation of organisms.

• Korean Journal of Environmental Agriculture
• /
• v.5 no.1
• /
• pp.24-29
• /
• 1986

This study was carried out to determine the heavy metal contents in effluents, soils and plants grown on the soils from 1982 to 1983. The heavy metal pollution of Keumho river was resulted from Sincheon, Kongdancheon and Dalseocheon. The urban sewage influxes in Sincheon and Dalseocheon whereas the industrial wastewater flows in Kongdancheon. The average heavy metal contents of effluents in these streams exceeded the Korean Standard Environmental value. The high level of heavy metal contents in soils and plant tissues should be originated from the polluted river water. The heavy metal contents of soils were significantly positively correlated with that of plant.

• Economic and Environmental Geology
• /
• v.48 no.6
• /
• pp.467-475
• /
• 2015

The Deokjin Pond is one of the places representing Jeonju City's history but has the poor water quality. The pond has a storage of $88,741m^3$ and a drainage area of $3.77km^2$. It has been maintained only by the groundwater pumped from the upstream wells and the direct rainfalls on the water surface since the old streams replenishing the pond were turned into a part of the sewer system due to indiscreet urbanization. The lack of replenishing water as well as the organic-rich bottom sediment were suggested as two main causes deteriorating the water-ecosystem. In this study, possible measures obtaining waters for restoration of Deokjin Pond ecosystem are discussed. It is estimated that the present pond can be replenished about 32 times a year by the runoff when the drainage system in the watershed is recovered to a state before urbanization. To support this, the drainage system is compared with that of nearby Osong Pond, which shows relatively better water-ecosystem. Even though Osong Pond has a drainage area one-seventh of that of Deokjin Pond, its storage is more than the half of it. It is because its watershed has a near natural drainage system where the rain mostly infiltrates into soil and slowly discharges into the pond. Therefore, it is believed that the low impact development (LID), which is known as a technique restoring the water circulating system to a condition before development, would be helpful in obtaining waters required for Deokjin Pond ecosystem management.