• Animal cells and systems
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• v.15 no.2
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• pp.169-177
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• 2011

In August 2002, a heavy rainfall (445 mm in total for 5 consecutive days) resulted in a catastrophic flood, and it completely washed away the benthic fauna from the mainstream channel of the Gapyeong stream, a typical mid-sized stream in the central Korean peninsula. This study was to investigate the recovery patterns of aquatic insect communities that were damaged by the flood. Aquatic insects were sampled quantitatively using a Surber sampler ($50{\times}50$ cm, 1 riffle and 1 pool/run habitats per site) from three sites (4th-6th order) of the Gapyeong stream prior to 2000 and seasonally after the flood event from 2003 to 2006. Before the flood in the reference year (2000), a total of 77 species of aquatic insects were collected, whereas after the flood 47 species (2003), 51 species (2004), 64 species (2005) and 55 species (2006) were collected from the whole sampling sites. The aquatic insect density decreased to 26.85% (2003), 90.25% (2004), 52.53% (2005) and 54.95% (2006) of that recorded in the reference year. Although approximately 70% of the aquatic insect fauna has recovered since the flood event, the species composition in the most recent year differed substantially (similarity ca. 50%). On the other hand, the compositions of functional groups have not significantly changed. Aquatic insect communities at the riffle sites were affected more profoundly than those at the pool/run sites. The aquatic insect communities at the upstream site recovered more rapidly than those at the downstream sites.

• Ecology and Resilient Infrastructure
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• v.5 no.3
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• pp.145-155
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• 2018

In a monsoonal climate, the soil seed bank can play an important role in plant regeneration after the severe annual floods that disturb above-ground vegetation within the riparian zone. To investigate the relationship between the soil seed bank and vegetation, we measured the species composition of the soil seed bank and the extant above-ground vegetation in six major plant communities (Artemisia selengensis, Miscanthus sacchariflorus, Persicaria nodosa, Phalaris arundinacea, Phragmites japonica, and Rorippa palustris) in the Cheongmicheon Stream, Korea. A total of 21 species germinated from the floodplain soil seed banks. The most diverse seed bank (21 species) was found in the A. selengensis community, wheres the lowest number of species was found in the R. palustris community (2 species). Most soil seed banks were composed of annuals (90%), exceptions being Rumex crispus and Artemisia princeps, which are perennial ruderals. The similarity of species composition between the soil seed bank and above-ground vegetation was low with Sorensen's similarity indices averaging 29% (range 12 - 42%). Crucially, existing dominant perennials of the extant vegetation including A. selengensis, M. sacchariflorus, P. japonica and P. arundinacea were absent from the soil seed bank. In conclusion, the soil seed banks of the floodplains of the Cheongmicheon Stream were mainly composed of viable seeds of ruderal plants, which could germinate rapidly after severe flood disturbance. The soil seed bank may, therefore, be useful for the restoration of the early succession stages of riparian vegetation after flood disturbances.

• Journal of Wetlands Research
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• v.16 no.4
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• pp.463-476
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• 2014

The riverine wetlands located in the riverside bring about social conflicts through confrontation between flood control value through flood control project and ecological preservation value of riverine wetland. In this study, we identified the importance of both values through analysis of economic feasibility of flood control and ecological values of riverine wetland, and tried to suggest management plans for riverine wetland considering both of flood control safety and ecological preservation through these results. For this, we calculated the expected annual flood damage of Imjin River using the multi-dimensional flood damage analysis(MD-FDA), and calculated the total value of riverine wetland using the contingent valuation method(CVM) to estimate preservation value of riverine wetland. The result of the analysis shows that the Imjin River needs flood control project and the ecological preservation of riverine wetland is also important. Therefore, the establishment of the management plan for protecting riverine wetland is also needed. As a result, the Imjin riverine wetland was classified as the area where sedimentation continues to take place, and the flood water level to rise. On the basis of the analyzed results, it is judged that the Imjin River needs flood control for public safety and ecological consideration for ecosystem preservation in the river improvement project. So, the stepwise river improvement is desirable to protect riverine wetland and minimize ecosystem disturbance. The results is expected to be made good use as the basic study for establishment of institutional river management plans considering flood control project and riverine wetland preservation in the future.

• Ecology and Resilient Infrastructure
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• v.9 no.2
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• pp.83-92
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• 2022

The 2020 summer extreme flood severely disturbed the riparian ecosystem of the Seomjin River. Some trees were killed by the flood impact, whereas others have recovered through epicormic regeneration after the disturbance. At the same time, several tree individuals newly germinated. This research aimed to explain the recovery of the riparian ecosystem by spatial proximity between each tree individual of different characteristics, such as "dead", "recovered", and "newly germinated". A spatial point pattern analysis based on K and g-functions revealed that the newly germinated trees and the existing trees were distributed in the spatially clumping patterns. However, further detailed analysis revealed that the new trees were statistically less attracted to the recovered trees than the dead trees, implying competitive interactions hidden in the facilitative interactions. Habitat amelioration by the existing trees positively affected the growth of the new trees, while "living" existing trees were competing with the new trees for resources. This research is expected to provide new knowledge in this era of rapid climate change, which likely induces stronger and more frequent natural disturbance than before. Environmental factors have been widely used for ecosystem modeling, but species interactions, represented by the relative spatial distribution of plant individuals, are also valuable factors explaining ecosystem dynamics.

• The Journal of the Convergence on Culture Technology
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• v.9 no.2
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• pp.215-220
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• 2023

Network technology used as a physical interface to retrieve, store, and exchange data is leading the era of data capitalism in the 21st century. The capacity of network technology dominates almost all communication in everyday life, and makes social understanding and experiences in the physical world visible in cyberspace. The movements of human bodies and objects in cyberspace are placed in a social context. This paper paid attention to these phenomena and examined the cases of activism that raised real problems through cyberspace. In particular, the focus of the study is the digital activism of the Electronic Disturbance Theater, which combines critical art and thinking for democracy with the realm of information and demonstrates aesthetic imagination. The first chapter of the main body briefly outlines the meaning activism as a social movement in cyberspace. The second chapter looks back on the alternatives of <FloodNet>, which represents the early activism performance of EDT. And then in the last chapter, the poetic significance of the <Transborder Immigrant Tool> is analyzed. Through this process, this paper demonstrates that the activism performance of the EDT is a critical aesthetics that encourages imagination for alternatives. It also argues that Electronic Disturbance Theater has contemporary value as an avant-garde art that actively utilizes the medium of network technology and integrates performance art and politics.

• Ecology and Resilient Infrastructure
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• v.8 no.2
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• pp.79-87
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• 2021

Because active interactions occur among vegetation, hydrology, and geomorphology in riparian systems, any changes in one of these factors can significantly affect the other two. In this study, we evaluated these interactions at four sites (two in Gajeong and two in Hahan) along the Seomjin-gang River that was substantially devastated by an extreme flood in 2020. We examined the relationship between the riparian vegetation and the hydraulic characteristics of the flood using remote sensing, hydraulic modeling, and field surveys combined. The evaluation results showed that the floods caused a record-breaking rise of up to 43.1 m above sea level at the Yeseong-bridge stage gauge station (zero elevation 27.4 m) located between the Gajeong and Hahan sites, with the shear stress being four times higher in Hahan than in Gajeong. Additionally, the water level during the flood was estimated to be a maximum of 1 m higher depending on the location in the presence of riparian plants. Furthermore, both sites underwent extensive biological damage due to the flood, with 78-80% loss in vegetation, with preferential damage observed in large willow species, compared to Quercus acutissima. The above findings imply that all plant species exhibit different vulnerabilities towards extreme floods and do not induce similar behavior towards events causing a disturbance. In conclusion, we developed strategies for effectively managing riparian trees by minimizing flood hazards that could inevitably cause damage.

• Ecology and Resilient Infrastructure
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• v.11 no.2
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• pp.43-54
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• 2024

Recently, most of the rivers in Korea are experiencing various problems in dimension and river environment, such as expansion of stable area where disturbance does not occur during flood, increase of excessive trees in river channel, fixation of river channel, reduction of sand bar. When the soil supplied by the flood is deposited in the river, the plant is settled in the formed terrain, and when another disturbance of the scale that does not erode there occurs after the plant is settled, the river gradually grows and the vegetation zone is formed there. In particular, in terms of river management, river forestation and river aggradation are objects that must be managed because they are disadvantageous in terms of flood control by lowering the flow rate and raising the water level. Therefore, in this study, the area of vegetation occupied by the year of sandbar was analyzed in the process of river aggradation in Jang-Hang wetland. In addition, the correlation between the growth of Jang-Hang wetland was analyzed through the analysis of the flow rate and the flooding frequency that directly affect the growth of Jang-Hang wetland. Through this, the management plan of Jang-Hang wetland, which is registered in Ramsar Wetland but has been river forestation and is undergoing river aggradation, was proposed.

• Spatial Information Research
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• v.6 no.1
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• pp.77-90
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• 1998

The complex interactions of climate, topography, geology, biota and hwnan activities result in the land cover patterns, which are impacted by natural disturbances such as fire, earthquake and flood. Natural disturbances disrupt ecosystem communities and change the physical environment, thereby generating a new landscape. Community ecologists believe that disturbance is critical in determining how diverse ecological systems function. Fires were once a major agent of disturbance in the North American tall grass prairies, African savannas, and Australian bush. The major focus of this research was to develop stochastic model of spatial process of disturbance or spatial events and simulate the process based on the developed model and it was applied to the fire arrival process in the Great Victoria Desert of Australia, where wildfires generate a mosaic of patches of habitat at various stages of post-fire succession. For this research, Landsat Multi-Spectral Scanner(MSS) data covering the period from 1972 to 1994 were utilized. Fire arrival process is characterized as a spatial point pattern irregularly distributed within a region of space. Here, nonhomogeneous planar Poisson process is proposed as a model for the fire arrival process and rejection sampling thinning the homogeneous Poisson process is used for its simulation.

• Proceedings of the Korean Society of Agricultural Engineers Conference
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• 2005.10a
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• pp.193-198
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• 2005

The solar energy floodgate which discusses will minimize a quotient bringing up for discussion friction resistance and it will do to write a disturbance power, with the base which will reach it will be able to use the solar power unit in order. It is a plan which to magnification supply the practicality and will give proof will the effort with the irrigation facility of the farming village. Magnification supply of the solar energy floodgate which it sees hazard the stack supervisor and the possibility the use against the farmer and the easy frost does the monitoring against and the work which it complements is necessary.

• Journal of Korean Society for Geospatial Information Science
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• v.12 no.1 s.28
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• pp.69-77
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• 2004

Since there are a lot of changes in climate on domestic and natural disasters owing to the disturbance-development of the land, damages of properties and human life frequently occur due to the coastal floodings. Accordingly, it is necessary to find the area where the danger of flooding coasts is relatively high and to inform resident the characteristics of the area As a part of preventive land management to minimize the flooding damages of the coastal area, this study suggested the generation of the coastal flood hazard map that provides detailed information such as refuge path, a place of refuge, and the location of medical supplies, food, and main rescue equipment, etc. This study selected the southern region of Daebu-do as an exemplary area, conducted a document study to establish GIS data, secured pre-structured data, and suggested the method of establishing GIS data fit to the study area. In particular, it emphasized the efficient construction of the geographical spatial data that were accurate, economic, objective, and realistic in supporting the modeling to predict the flooding zone. The specific type of established database was divided into flooding risk area, flooding warning area, and flooding-volume area. The prototype of coastal flood hazard map can be widely used for efficient disaster management. Furthermore, it is considered that the map could be applied for arousing residents' attentions to the flooding, prior education, and local governments' management actions against the danger of flooding.