• Journal of Wetlands Research
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• v.17 no.2
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• pp.124-129
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• 2015

In order to get as ecological basic data for river restoration, vegetation investigation was conducted in natural river and analysed it synecological methods, such as ordination cluster. 29 plant communities units were identified and the major dominant plant communites were Quercus mongolica community, Pinus densiflora community, Populus davidiana community, Q. variabilis community and Prunus sargentii community. River vegetations were classified into ravine and gorge forest type and riverine softwood forest type. Ravine and gorge forest was dominanted by hardwood which located in steep slope and in high elevation, and riverine softwood forest by softwood, salix spp. Naturality was an important criterion for the selection of rivers, so many of the selected rivers are located in the upper stream and mid stream rather than the lower stream, where more human intervention is involved. Plant communities were consisted of hardwood forest(44 plots, 92%) and softwood forest(4 plot, 8%), respectively. PCA with total layer data showed 5 groups of communities: Q. mongolica community group, Prunus sargentii community group, Pinus densiflora community group, Prunus sargentii community - Pinus densiflora community group and the rest communities group. PCA with tree layer showed 3 groups: Q. mongolica community group, Prunus sargentii community group, and the rest community group. Cluster analysis also a showed a similar communities group to PCA ordination, but Magnolia sieboldii community and Prunus sargentii community were distinguished from the PCA result. From the result, it can be concluded that the plant communities of riparian be divided into hardwood and softwood forest by statistical techniques. It was appropriate to plant species such as Quercus mongolica, Pinus densiflora, Populus davidiana, Quercus variabilis and Prunus sargentii, at levee zone and high water level. And Sliax spp. were appropriate for planted plants at waterfront and low water level. The herb species to be planted on the floodplain were recommanded in the species composition co-occurred with the woody species.

• Journal of Korea Water Resources Association
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• v.45 no.9
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• pp.929-941
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• 2012

In recent years, interest in river environment such as riparian landscape, water quality and ecological conservation has been growing with increasing recreation on agricultural river watershed. That caused the increase of necessity of water resources development, one of solutions for the diversification of agricultural water demand and shortages. In this respects, heightening irrigation dam, as a part of the 4-major river restoration project, is necessary to secure not only additional agricultural water but also instream flow for water quality improvement. However, operation plan of irrigation dam still not be clear. In this study, additional storage which secured through heightening irrigation dam was estimated using SWAT model. And instream flow effects on water quality of downstream were evaluated. The findings show that the additional water supply will contribute positively to water quantity and quality of downstream. The results show a 2~10% water quality improvement effect on nutrients, as well as an 1~8% water quantity increasing effect. In particular, additional storage can be effectively supplied from February to April by the reservoir operation. However, maintaining better water quality in irrigation reservoirs is important because the water quality of irrigation reservoirs can be negatively impacts the water quality in downstream of reservoirs.

• Journal of the Korean Institute of Landscape Architecture
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• v.37 no.6
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• pp.96-105
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• 2010

This study identified the dynamic process of sandbar and vegetation distribution of the sandbar on the Tan-cheon River. The study area is located in the lower reaches of the Tan-cheon River that has been managed as an Ecosystem Reserve Area since 2002. For the study, the geomorphological process was analyzed through mapping analysis using a satellite image followed by analysis of the vegetation distribution through an on-site survey. The major findings were as follows : First, In the fluvial geomorphic process, various kinds of sandbars were developed in 1990s, the morphologic characteristics changing continuously. Second, In the distribution of vegetation on the sandbar, the sandbar shore was covered with bare sand substrate or intermittent annual vegetation because of the periodic fluctuation of the water-level due to intensive disturbances. Third, In the relationship between the sandbar formation and vegetation, four types of sandbars were classified: channel-shore stable bar, channel-shore unstable bar, mid-channel stable bar and mid-channel unstable bar, according to the fluvial disturbance & vegetation process. The study verifies that the vegetation distribution is reciprocally related to the geomorphological process. Accordingly, it is meaningful in the selection of plant species and the planting area of the sand bar. However, it is limited to the planting guidelines on river restoration projects. More diverse on-site experimental studies should be conducted.

• Journal of Wetlands Research
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• v.19 no.4
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• pp.433-442
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• 2017

As a result of the Four-River Restoration Project in Korea, the habitat of endangered plant species of Aster altaicus var. uchiyamae and Polygonatum stenophyllum, which had been natively grown in the riparian zone of Namhan River, was destroyed and artificial replacement habitats were created. In this study, Habitat Suitability Index (HSI) was used to determine whether the replacement habitats are suitable for each species or not. From October 2015 to July 2016, Habitat Evaluate Procedures (HEP) were conducted on two replacement habitats of A. altaicus var. uchiyamae (Gangcheonsum and Sum-River) and on two replacement habitats of P. stenophyllum (Gangcheonsum and Youngjuk) in the Namhan River watershed. As evaluation parameters for A. altaicus var. uchiyamae habitat, habitat matrix (ratio of unburied gravel), height above the ordinary water level, soil nutrients, and light conditions were selected and for P. stenophyllum habitat, soil texture, light conditions, and coverage of companion species were selected. HSI was applied to evaluate the suitability of each replacement habitat. According to the result of the evaluation, replacement habitats of A. altaicus var. uchiyamae and P. stenophyllum located in Gangcheonsum have relatively high HSI values as 0.839 and 0.846, respectively. On the other hand, replacement habitats of A. altaicus var. uchiyamae in Sum-River and P. stenophyllum in Youngjuk zone have HSI value of 0, indicating unsuitable habitats for these species. This is the first attempt to apply HSI for plant species in Korea and proved the usefulness of HSI on plants.

• Korean Journal of Ecology and Environment
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• v.36 no.1 s.102
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• pp.74-82
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• 2003

This study was carried out to understand how the bird community would change in a stream ecosystem after implementation of close-to-nature river improvement techniques conducted on the Gwacheon, Seocho and Hakyeul reaches in the Yangiae Stream, 'Seoul. At the Gwacheon reach, the number of species and individuals tended to decline. However, at the Seocho reach, the number of species was increased while the number of individuals appeared to be not changed greatly. Especially, density of Dabbling Ducks were rapidly increased. At the Hakyeul reach was both the number of species and the number of individuals were increased. Density of Herons and Dabbling Ducks rose, while density of Wagtails was decreased suddenly. Except the Gwacheon reach, the survey areas were gradually improved in species richness and density after the construction of river improvement. We suggested that the naturally-formed meandering (channel) bar, restoration of riparian vegetation and artificial ponds were helpful for birds habitation, however bicycle path constructed in flood plain was negative.

• Korean Journal of Environment and Ecology
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• v.26 no.2
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• pp.247-256
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• 2012

We evaluated the landscape ecological value of selected minefields and wetland patches as a habitat of the forest bird community. The avian fauna of three minefields of 8.5ha, 17.4ha, and 40.6ha were evaluated by comparing that of three control sites of mountain area. Average number of forest bird species, number of individuals, species diversity index, species richness, and species evenness were analyzed according to the size of patch and environmental characteristics such as the presence of wetland and connectivity. Community similarity was evaluated between test and control plots. Avian fauna can be summarized as follows. First, 63 species were recorded, and the sum of maximum counts was 828 individuals. Species diversity index was 3.8, and the species richness was 9.2. Species evenness was 93.3. Second, small, isolated forest patch had a low average number of species and individuals as expected. But, small forest patches with streams had higher bird density than patches without water surface. Third, forest patches with marsh wetland were evaluated as lower habitat quality than forest patches with stream wetland in terms of the number of bird species per unit area, number of individuals per unit area, species diversity index, species richness index, and species evenness. Finally, Community similarity of the small forest patches with streams was similar with large connected forest. As a result, lowland forest patch was shown the good quality for the forest bird community in spite of small extents, and community structure was similar with mountain forest bird community. Thus, riparian forest restoration could improve the biodiversity of the forest bird community.

• Ecology and Resilient Infrastructure
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• v.6 no.4
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• pp.267-276
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• 2019

The Gonggeomji Reservoir is a historical irrigation facility built in the 8th century and designated as a wetland protected area by Ministry of Environment, Korea. In order to collect the baseline data necessary for developing a sustainable conservation strategy, we investigated the classification of actual vegetation, the vegetation distribution and the floristic structure of the vegetation in the Gonggeomji Wetland Protection Area. In the whole protection area, a total of 26 plant communities were classified including the wetland, riparian, grassland, forest, farmland, and orchard vegetation. According to the results of detrended correspondence analysis, the structure of wetland vegetation was mainly affected by water depth and human disturbance. In reservoir wetlands, floating vegetation such as Utricularia vulgaris var. japonica, Trapa japonica, and emergent vegetation such as Nelumbo nucifera, Typha spp. completely covered the water surface. Since 2014, the reservoir wetland has been terrestrialized with the expansion of emergent and hygrophytic plants. For the sustainable conservation and restoration of wetland protected areas, it is necessary to naturalize the topography and wetland vegetation, recovery the hydrologic system, and restore ecosystem connectivity from wetlands to forests.

• Korean Journal of Environment and Ecology
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• v.21 no.5
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• pp.390-399
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• 2007

We analyzed the vegetation environment at the stream section of habitat in which Cottus koreanus lives. The plant communities were classified into Fraxinus rhynchophylla community, Acer ginnala-Salix koreensis community, Phragmites japonica-Salix gracilistyla community, Salix gracilistyla community, Phragmites japonica community, Robinia pseudo-acacia community, and Oenanthe javanica-Persicaria thunbergii community. The frequency of Phragmites japonica-Salix gracilistyla community was the most. And also the frequencies of Fraxinus rhynchophylla community and Salix gracilistyla community were high. In stream bank zone and terrace zone, the typically represented vegetation was the Fraxinus rhynchophylla community and Acer ginnala-Salix koreensis community and Phragmites japonica-Salix gracilistyla community, respectively. The rNCD of the top-priority plants applied to restoration of the vegetation in stream bank zone came out by the order of Ulmus davidiana var. japonica, Salix koreensis, Acer ginnala, Salix gracilistyla, and Fraxinus rhynchophylla. The rNCD in terrace zone was arranged by the order of Salix gracilistyla, Phragmites japonica, and Artemisia princeps. The spatial distribution of vegetation was the most greatly influenced by cross-sectional position of the surveyed stream, and this aspect is believed to be due to the habitat's physical stability. Species diversity also obviously makes a great difference depending on their surrounding physical stability.

• Journal of Wetlands Research
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• v.12 no.3
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• pp.21-37
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• 2010

The abiotic factors and the vegetation naturalness of the 13 tributary wetlands around Namgang-River were assessed to investigate the present state and to present the conservation counter plan for the wetland ecosystem of the tributaries. Assessment indices for the abiotic factors were estimated based on the dominant land use types of the riparian zone, ecological function of the upper levee, levee slope structure, artificiality and utilization intensity of the waterfront, artificiality of the revetment structure, diversity of the substrate, and severance of the transverse. The assessment index of Omi-cheon is the highest among 13 tributaries. The second was Banseong-cheon and third was Hyangyang-cheon, followed by Nabul-cheon and Yeongcheon-gang and Sugok-cheon, Jungchon- cheon, and Daegok-cheon in their order and Munsan-cheon got the lowest assessment index. Assessment indices for the vegetation naturalness were estimated based on the vegetation diversity, exotic species dominance, annual herb dominance, naturalness and peculiarity of the vegetation, and species diversity. The assessment index of Omi-cheon is the highest among 13 tributaries. The second was Sugok-cheon and third was Banseong-cheon, followed by Yeongcheon-gang, Jungchon- cheon, Jinae-cheon, Nabul-cheon, and Jisu-cheon in their order, and Yonga-cheon got the lowest assessment index. The grades of the stream naturalness were estimated based on the the naturalness indices for the abiotic factors and the vegetation naturalness. The grades of Omi-cheon is the highest among 13 tributaries as the grade I. Those of Banseong-cheon, Sugok-cheon, Yeongcheon-gang, Nabul-cheon and Jungchon-cheon, Hyangyang-cheon, Jinae-cheon, Jisu-cheon, Daegok-cheone, and Munsan-cheon and Doksan-cheon were grade II in their order, and Yonga-cheon got the lowest as the grade III. It was suggested that restoration of the simple and flat substrate, create the natural vegetation on the levee slope constructed with concrete or stone wall, and rehabilitation of the eco-bridge were demanded to improve the grades of the stream naturalness through the restoration of the tributaries for the diverse aquatic wildlife, high vegetation diversity and species diversity with the vegetation consisted of perennial herbs and trees.

• Korean Journal of Ecology and Environment
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• v.52 no.3
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• pp.245-265
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• 2019

Biotope, which represents the characteristic habitats of living organisms, need to be identified as essential for the efficient creation and sustainable management of urban ecosystems. This study was carried out to provide the basic information for ecological urban planning by analyzing types and attributes of the biotop established throughout the whole area of the Pohang city, a representative industrial city in Korea. The biotop established in Pohang city is composed of 12 types including forests (coniferous, deciduous, and mixed forests), agricultural fields (rice paddy and upland field), green facilities, river, reservoir, bare ground, residential area, public facilities, commercial area, industrial area, roads, and schools. As a result of analyzing the properties according to biotop types, industrial, commercial and residential areas, which represent urban areas, was dominated by introduced vegetation. Moreover the introduced vegetation is usually composed of exotic plants or modified forms for landscape architecture and horticulture rather than native plants, which reflects ecological property of both region and site. As the distance from the urban center increases, the agricultural field showed a form of typical farmland, whereas the closer it is, the more form of greenhouse farming. Natural green spaces were divided into riparian vegetation established along the stream and forest vegetation. Forest vegetation is consisted of secondary forests (seven communities) and plantations (three communities). The urban landscape of Pohang city is dominated by the industrial area. Among them, the steel industry, which occurs large amounts of heat pollution and carbon dioxide, occupies a large proportion. On the other hand, green space is very insufficient in quantity and inferior in quality. This study proposed several restoration plans and further, a green network, which ties the existing green spaces and the green space to be restored as a strategy to improve the environmental quality in this area.