• Ecology and Resilient Infrastructure
• /
• v.3 no.1
• /
• pp.70-75
• /
• 2016

The purpose of this study was to develop water-purification vegetation mats consisting of the eco-friendly materials and to validate their water purification capabilities with the objective of reducing nonpoint pollution into streams. The developed vegetation mats are made of coconut fiber shell and filling consisted of zeolite, diatomaceous earth or a mixture of calcinated foam media. The bench scale assessment of the water purification capability of the three filling materials showed that the removal efficiencies of suspended solid (SS), total nitrogen (T-N) and total phosphorus (T-P) were higher in the foam media than in zeolite or diatomaceous earth. From the results of the field experiment, the removal efficiencies of the vegetation mats filled with the foam media were 60.1% in SS, 32.2% in T-N and 20.2% in T-P. Therefore the vegetation mats filled with the foam media calcinated from zeolite and diatomaceous earth should have higher efficiencies in controlling the nonpoint source pollutions in streams.

• Journal of the Korean Society of Environmental Restoration Technology
• /
• v.16 no.4
• /
• pp.15-26
• /
• 2013

In recent years, river maintenance projects using natural methods have been continuously implemented in urban areas and methods emphasizing ecology are being developed and constructed in revetment areas. However, there is insufficient technical review on the hydraulic stability of those revetment methods during the event of flood. Therefore, a hydraulic analysis is necessary for the stream where revetments are applied. This study was conducted to develop an objective test method for the hydraulic stability of green revetment media. For this purpose, hydraulic model tests were performed for the green base materials for revetments. Tests were conducted using experimental devices for the hydraulic model which were installed to simulate the rapid current during the flood. Loss of soil by the hydraulic condition was compared and analyzed with that of dry green revetment media, and the evaluations were made on the corrosion resistance, tractive force, and contractile force. Test results showed that green revetment media had higher corrosion resistance in non-vegetation condition compared to dry green revetment media, and the loss of base materials by the rooting of vegetation showed significant reduction by the vegetation. In addition, results of the allowable tractive force of the base material indicated it is relatively stable in vegetation condition but scouring can occur in non-vegetation condition. Therefore, the development of vegetation in revetment areas is anticipated to be effective for the stability of revetment areas by reducing external forces interacting with the corrosion resistance and stream bank. The green revetment media in expected to contribute to the stability of revetment areas.

• Journal of the Korean Society of Environmental Restoration Technology
• /
• v.15 no.6
• /
• pp.61-67
• /
• 2012

This study was conducted to evaluate the effects of soil covering and vegetation base materials implementation on the growth of Lespedeza cyrtobotrya Miq. in abandoned coal mine land. We compared the biomass of L. cyrtobotrya at the study plots of four different soil covering depth (control, 10cm, 20cm, and 30cm) and four different compounds of vegetation base materials composed of soil conditioner (S), erosion control (E), and peat moss (P) (control, S+P, E+P, and S+E+P). The result showed that the biomass of L. cyrtobotrya was higher in the study plots implemented with soil covering than control plot, although the increase in biomass was not constant with soil covering depth. In case of the vegetation base materials treatments, the biomass was highest in S+E+P plot, and S+P and E+P plots showed higher biomass than control plot.

• Journal of the Korean Society of Environmental Restoration Technology
• /
• v.5 no.2
• /
• pp.9-16
• /
• 2002

Wetland areas have characteristics of dynamic cycling of materials in relation to land and water. Although having great potential for providing unique natural environments, they are vulnurable to human land use activities and some places are in danger of being eliminated. This study had an objective of investigating vegetation changes in Ilwol reservoir to provide basic information for the preservation and ecological restoration of the wetland area. Wetland vegetation was investigated along with the site conditions which may affect the vegetation development. There were 10 vegetation types with various species composition. Humulus japonicus, Zizania latifolia, Phragmites japonica, Bidens frondosa, Typha orientalis, Scirpus tabernaemontari, Phragmites communis, Persicaria thunbergii were the major wetland plants found at the reservoir area. Precipitation and water level were the elements mostly affecting the distribution of the plants. Phragmites japonica was closest to the water front, followed by Zizania latifolia, Humulus japonicus and Bidens frondosa. Most plant zones were predominated by one or a few species.

• Journal of Environmental Science International
• /
• v.22 no.2
• /
• pp.195-203
• /
• 2013

I investigated the river morphology and river naturality according to the environment of the Hwang River. The numbers of flexions at the upstream regions were more than those of downstream regions. The Hwang River showed very low overall diversity of the flow. Materials of river shore at low channel width were mainly boulders or gravel at the upstream regions, and the middle and downstream were silts and clay. Artificial masonry and natural materials were mixed from materials of river levees. The Hwang River was some of the natural herbaceous vegetation to riparian zones. Land utilities for floodplain were extremely overall farmland were predominant, and partly used by natural vegetation in the forest, a soccer field, some park facilities, residential, and commercial facilities. The water was width sleep / rivers beam ratio of 10 to 20%. Currently estimation for river naturality widely used in rivers were consisted of a narrow wide a variety of items and did not reflect the actual.

• Journal of the Korean Institute of Landscape Architecture
• /
• v.28 no.2
• /
• pp.97-107
• /
• 2000

This study aims to develop the model of evaluation on greenspace to increase the sustain ability of the planning and management for site-scale development projects. The results of this study can be summarized as follows: (1) The comprehensive principles of sustainable development projects were established, which include coexistence of man and nature, reflection of ecological principles, minimization of environmental pollution and damage, recycling and reuse of materials. (2) According to established principles, the evaluation criteria were classified into seven categories as follows: retention of ample greenspace, formation of greenspace as a habitat, species diversity of vegetation, consideration of indigenous plants, construction of green network, conservation of greenspace, and reuse of plant materials. (3) As a result of the analysis of questionnaire of experts, evaluation model was worked out with which we can evaluate environmental friendliness greenspace. And, the final evaluation indicators for greenspace are the rate of greeneries volume, securing habitat, indigenous plants, reuse of plant materials, and species diversity of vegetation, and the indicator of greenspace conservation.

• Journal of the Korean Institute of Landscape Architecture
• /
• v.27 no.2
• /
• pp.58-68
• /
• 1999

This study was carried out to verify the distribution patterns of Salix gracilistyla and Phragmites japonica communities known as obligatory riparian species according to physical factors such as micro-landforms, substrates, etc., at Soo-ip stream corridor. Firstly four vegetation types - Salix gracilistyla dominant type, Phragmites japonica dominant type, mixed type of two species, and mixed type of two species to other species, were classified by cluster analysis based on UPGMA-Euclidean distance. Also these vegetation types showed many different distribution patterns in response to the longitudinal and lateral view along the stream corridor and substrate composition. Salix gracilistyla was major component of dominant vegetation types developed at attack point of bending reach and on substrates composed of rock fragments, but contrastly Phragmites japonica was most important component of dominant vegetation types at point bar of bending reach and floodplain, and on substrates composed of soil materials. Secondly the species and environment biplot form CCA strongly supported the vegetation types divided by classification. Namely Salix gracilistyla was closely correlated with rock fragments and steep slope, which is resistant to physical action even though located near running water. But Phragmites japonica showed a high correlation with soil particles sedimented at floodplain by divergent flow.

• Proceedings of the Korea Water Resources Association Conference
• /
• 2003.05b
• /
• pp.919-922
• /
• 2003

• Journal of Korean Society of Forest Science
• /
• v.101 no.1
• /
• pp.130-137
• /
• 2012

This study has conducted to develop new gabion wall systems with vegetation base materials for stream bank stability and rapid rehabilitation. Vegetation base materials are primarily compounded with fine soil, organic composts and peat moss as plant fibers, a water retainer and a soil improver. Normally gabion wall systems resist the lateral earth pressures or stream power by their own weight. Therefore, fill material must have suitable weight, compressive strength and durability to resist the loading, as well as the effects of water and weathering. In this project, 100 to 200-mm clean, hard stones are basically specified, and about 50-mm rubbles are also used. Test application of new gabion wall system carried out in the stream bank of a small stream in the Gwangreung experimental forest, belonging to Korea Forest Research Institute (KFRI) in December 16th, 2006. As a result of the analysis of hydraulic stability of new gabion wall system, gabion wall system has highest threshold shear stress when the gabion wall covered by vegetation. New gabion wall system is highly resistant to sliding and overturning because safety coefficients exceed 1.5. As a result of term of slope stability analysis of new gabion wall system by Bishop and Fellenius methods, stability of stream bank was highly increased after the construction of gabion wall. Therefore, new gabion wall system is effective to stabilize unstable stream bank.

• Journal of Korea Water Resources Association
• /
• v.49 no.1
• /
• pp.73-81
• /
• 2016

This study investigates the development of lower channels and sediment sorting processes in the vegetated channels with the mixed sediment. The sediment discharges fluctuate with time and decrease with vegetation density. The bed changes with irregular patterns, and the sediment particles in the vegetated zone at the surface of bed are fine. The dimensionless geometric mean decreases with vegetation density. The fine sediment particles are trapped by vegetation, and the bed between main steam and vegetated zone increases. Moreover, the particle sizes are distributed irregularly near the zone. The hiding functions decrease with dimensionless particle size. However, the functions increase with vegetation density, which is confirmed by decreasing sediment discharge with vegetation. The lower channel is stable and the migration decreases in the condition of $0.5tems/cm^2$. However, the migration of the lower channel in the condition of $0.7stems/cm^2$ increases due to the increased sinuosity and new generated channels in the sedimentated vegetation zone.