• Environmental Engineering Research
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• v.18 no.3
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• pp.151-156
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• 2013

Several soil properties were studied from three young created mitigation wetlands (<10 years old), which were hydrologically comparable in the Piedmont region of Virginia. The properties included soil organic matter (SOM), soil organic carbon (SOC), pH, gravimetric soil moisture, and bulk density ($D_b$). No significant differences were found in the soil properties between the wetlands, except SOM and SOC. SOM and SOC indicated a slight increase with wetland age; the increase was more evident with SOC. Only about a half of SOC variability found in the wetlands was explained by SOM ($R^2$ = 0.499, p < 0.05). The majority of the ratios of SOM to SOC for these silt-loam soils ranged from 2.0 to 3.5, which was higher than the 1.724 Van Bemmelen factor, commonly applied for the conversion of SOM into SOC in estimating the carbon storage or accumulation capacity of wetlands. The results may caution the use of the conversion factor, which may lead to an overestimation of carbon sequestration potentials of newly created wetlands. SOC, but not SOM, was also correlated to $D_b$, which indicates soil compaction typical of most created wetlands that might limit vegetation growth and biomass production, eventually affecting carbon accumulation in the created wetlands.

• Journal of Fisheries and Marine Sciences Education
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• v.20 no.2
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• pp.156-167
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• 2008

Meorological data have been collected to monitor the wetland area in Goheung bay since 2003 and four intensive observations were conducted to study effects of the atmospheric turbulence on the energy budget and the ecological changes. We improved an algorithm to estimate the sensible heat flux with routine data. The sensible heat flux estimated by gradient method was in good agreement with that measured by precision instruments such as surface layer scintillometer and ultrasonic anemometer. Diurnal variations of sensible heat flux showed analogous tendency to those of temperature gradient. When the vertical wind shear of horizontal wind components was weak, even though temperature gradient was strong, the gradient method underestimated the sensible heat flux. A compensation for the cloud will make this gradient method be a helpful tool to monitor the ecosystem without expensive instruments except for weak wind shear and temperature gradient.

• Korean Journal of Environment and Ecology
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• v.24 no.3
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• pp.249-257
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• 2010

The purpose of this paper is to weigh the possibility of endangered Jang-hang wetland at the estuary of Han River to be included on the Ramsar List of Wetlands of International Importance and come up with ways to manage the wetland depending on its biotope patterns. The target area is located between Gimpo bridge and Isanpo I.C. with about $2.7km^2$ area. Through the analysis of RIS(Information Sheet for Ramsar Wetlands), it was known that the wetland is located on the sedimentary topography and formed as a result of sediment at the estuary of the river owing to the concentration of rainfall during summer. The vegetation environment in the area is divided into brackish water and fresh water areas depending on salinity. Rhizosphere soil(RS) of the area was analyzed to be Silt loam while bottom RS to be Sand loam. The plant ecology was composed of 52 families 135 species and 11 varieties and 146 types. Among indigenous species found are Salix koreensis, Phragmites communis and Miscanthus sacchariflorus. The analyzed results of the actual vegetation showed that willow community accounts for 37% of the area and rice field is 13.5%. As for animal ecology, total of 62 species and 25,977 individual wild birds were observed. After comparing and analyzing the RIS we compiled with the Ramsar Site designation standards, it turns out that the Jang-hang wetland meets criteria 1(biographic region), criteria 2,3 and 4(species and ecological communities) and criteria 5 and 6(water birds). Thus, Jang-hang wetland is eligible for the Ramsar site. As a result of establishing and evaluating the biotope types for setting management areas, Jang-hang wetland has a total of 13 different types, and the grade I represents 75.4% of the area while the grade III 0.8% of the land status. We categorized four management zones for the wetland depending on the biotope patterns - preservation, restoration, use and buffer zones and suggested management methods for each zone.

• Journal of the Korean Institute of Landscape Architecture
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• v.51 no.3
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• pp.1-20
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• 2023

The present study has monitored the changes in the biodiversity of Dunchon-Dong ecological and landscape conservation area after the restoration of the wetland, identified and analyzed the threats to the ecosystem, and presented a management plan accordingly. In this area which was forests and rice paddies in the past, apartment reconstruction is currently underway, with some hinterland forests and wetlands remaining. When we look into the change in the floras, the total number of species was 193 in 2000 before the restoration, it decreased from 2004 to 2006, and as of 2019, it was 149, showing an increasing trend. The result of comparing the species that emerged before and after the restoration showed an increase in Cyperaceae herbs such as Carex maximowiczii and Carex dispalata growing in wetland areas within forests and Schoenoplectiella juncoides and Schoenoplectus tabernaemontani growing in areas within wetlands where shallow water is maintained. As a result of analyzing the change in the area ratio of each type of extant vegetation, the wetland native herbs formed the power at the highest ratio after the restoration. The change in the power of the wetland native herbs was on an increasing trend until 2007, after which it decreased much in 2010 and then gradually increased, showing values of 26.6% in 2000, 44.6% in 2002, 49.0% in 2005, 53.3% in 2007, 28.7% in 2010, and 37.3% in 2019. The cause of the decrease in 2010 was judged to be due to the vegetation management conducted to secure open water and remove organic matter in freshwater reservoirs. The amphibia which emerged from 2000 to 2019 was a total of 9 species including Hynobius leeshii, Bufo gargarizans, Kaloula borealis, and Rana uenoi. As a result of the changes in the emerging wild birds, the species diversity index before the restoration was 0.9922 in 2000, and the species diversity index after the restoration gradually increased to 1.2449 in 2005, 1.2467 in 2010, and 2.2631 in 2019. The amphibia and wild birds inhibiting in the Dunchon-Dong forest and wetland were judged to have increased through continuous wetland maintenance such as naturalized plant removal management, native plant maintenance, and open water securing management. For the ecosystem preservation management of the Dunchon-Dong ecological and landscape conservation area, it was suggested to minimize the impact of the Dunchon-Dong reconstruction project, reorganize the indiscriminate access roads adjacent to the wetland, and reorganize the main entrance to the wetland. For ecosystem restoration management, systematic restoration and ecological buffer planting were suggested to be carried out at the time of construction fence demolition.

• Journal of Environmental Science International
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• v.16 no.2
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• pp.233-239
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• 2007

In the coastal wetland the mud is consist of fine particles, which means that it is characterized by small gap, and heat transfer is obstructed since moisture is found between the gaps. The relationship between net radiation ($R_N$) and soil heat flux($H_G$) shows a counterclockwise hysteresis cycle, which refer to a time lag behind in the maximal soil heat fluxes. The albedo is independent of seasonal variation of the vegetation canopy which plays very important roles to store and control the heat in the atmospheric surface layer.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.8 no.6
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• pp.80-91
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• 2005

This research aims to classify wetland types and evaluate functions of a dam lake. The case study area is Boryung lake in Boryung City. In this study was carried out based upon field surveys, drawing maps and publication, and modified-RAM which can evaluate the general functions and conservation values of wetlands. Eight functions of 2-12 variables each are analyzed for assessing the wetland functions. The analysis shows that several types of wetlands were identified, such as Palustrine/ Perennial/ Hydrophytes, Palustrine/ Perennial/ Openwater, Palustrine/ Seasonal/ Herbal, Palustrine/ Seasonal/ Shrub and Scrub, Palustrine/ Seasonal/ Hydrophye, and Riparian/ Seasonal/ Shrub in the Boryung lake. The average level of functions of the wetlands is very "HIGH", and it is recommended that prompt conservation measures should be taken.

• Korean Journal of Environment and Ecology
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• v.17 no.2
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• pp.123-132
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• 2003

This ecological study investigated the vegetation changes of abandoned salt field, 21 plots(1${\times}$lm, 1${\times}$2m) set up by the methods of Braun-Blanquet and Elenberg in a coastal island, Gasado, Jindogun, from July to September,2002. The vascular plants of abandoned salt field in the surveyed site identified 17 families and 48 species. Of these species, halophytes and mesophytes were 20(42%) and 28(58%) species. In addition, the disturbance to this habitat led to the change of halophytes in abandoned sald field, exotic plants was distributed 23 species, which included Dactylis glomerata, Conyza canadensis, Oenothera odorata, Cosmos bipinnatus, etc., in the group of, mesophytes were 20(71%) species, vegetation communities were classified into 3 community types, i.e. the halophyte grassland community(Limonium tetragonum community, Suaeda japonica community, Spergularia marina community), the wetland grassland community(Phragmites communis community, Carex scabrifolia community, Phaceturus latifolius var. angustifolius community), and the mesophyte grassland community(Erigeron bonariensis community, Daucus littoralis var. koreana community). Each communities was described the structual, distribution and changes of the vegetation in the abandoned salt field, the vegetation table and actual vegetation map were prepared.

• Journal of Wetlands Research
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• v.18 no.1
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• pp.84-93
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• 2016

As a transition region between ocean and land, coastal wetlands are significant ecosystems that maintain water quality, provide natural habitat for a variety of species, and slow down erosion. The energy of coastal waves and storm surges are reduced by vegetation cover, which also helps to maintain wetlands through increased sediment deposition. Wave attenuation by vegetation is a highly dynamic process and its quantification is important for understanding shore protection and modeling coastal hydrodynamics. In this study, laboratory experiments were used to quantify wave attenuation as a function of vegetation type as well as wave conditions. Wave attenuation characteristics were investigated under regular waves for rigid model vegetation. Laboratory hydraulic test and numerical analysis were conducted to investigate regular wave attenuation through emergent vegetation with wave steepness ak and relative water depth kh. The normalized wave attenuation was analyzed to the decay equation of Dalrymple et al.(1984) to determine the vegetation transmission coefficients, damping factor and drag coefficients. It was found that drag coefficient was better correlated to Keulegan-Carpenter number than Reynolds number and that the damping increased as wave steepness increased.

• Journal of Environmental Science International
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• v.18 no.1
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• pp.99-111
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• 2009

In this study vegetation structure was monitored focusing on slanting surface of stream for the purpose of developing a management plan and ecological restoration of small stream in Paju. The study was conducted by types of geographical structure, yearly flora, naturalization rate changes, actual vegetation changes, plant community changes. Slope area of small stream in Paju was varied in the slope range of $10{\sim}35^{\circ}$. The survey results of yearly flora showed that 37 species appeared in 2000, 55 species in 2001, 95 species in 2002, and 125 species in 2003. Therefore, the trend of continuous increase of flora each year was observed. In the case of yearly changes of actual vegetation, indigenous wetland herb community including Phragmites communis$(19.99%{\rightarrow}18.42%{\rightarrow}19.60%)$ did not show substantial changes in the area, while the influence of controlled flora such as Humulus scandens$(8.86%{\rightarrow}5.26%{\rightarrow}9.73%)$, and Ambrosia artemisiifolia$(1.06%{\rightarrow}1.43%{\rightarrow}6.93%)$ were increased. The vegetation structure investigated by 18 preset belt-transects also indicated that Phragmites communis and Miscanthus sacchariflorus were maintaining the status or decreasing the population, while the population of Humulus scandens, Ambrosia artemisiifolia, Setaria viridis, and Erigeron canadensis were greatly increased. Our proposal management to restore ecology is as follows: first, preservation and restoration of Phragmites communis landscape; second, restoration of potential stream vegetation community; third, selection and removal of controlled plants.

• Journal of Environmental Impact Assessment
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• v.7 no.2
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• pp.53-64
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• 1998

This study was performed to build up the ecological guidelines to grasp the structure of the vegetation change which is due to river rehabilitation. Anyway, river ecosystem and function has been destroyed owing to river development. It is important that river vegetation supplies ecological corridor and biotope. Two survey sites(Wonsungcheon and Pungseocheon)were investigated in the aspect of plant ecosystem and structure to settle the practical concept of river ecosystem. Each survey site was subdivided to five plots. The site was surveyed through the belttransect method. Wonsungcheon gets more seriously polluted as it runs to the urban area. In other words, there are On the other hand, Pungseocheon has more naturality but its downstream is under the pressure of various wood plants in the upstream area, but downstream area is dominated by naturalized plants such as Bidens frondosa, Panicum dichotomiflorum, etc. Riverbank of downstream has been changed into farm and parking lot. development. It should be preserved definitely because it still has abundant naturality and wetland which formed a biotope. The objective of the research is to find out the river retrogression and maintenance methods based on the riparian vegetation structure. To manage the river ecologically, hydrophytes should be induced partly for natural purification after the riverside is rehabilitated. The vegetation should be induced step by step to restore natural river and steady monitoring and research are required.