• Journal of the Korean Association of Geographic Information Studies
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• v.15 no.1
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• pp.99-118
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• 2012

The aim of this study is to define a correlation between spatial distribution characteristics of FFG(Functional Feeding Groups) of aquatic insects and related environmental factors in the Geum River based on the theory of RCC(River Continuum Concept). For that objective we had used SMRA(Stepwise Multiple Regression Analysis) method to analyze close relationship between the distribution of aquatic insects and the physical and chemical factors that may affect their inhabiting environment in the study area. And then, a probabilistic method named Frequency Ratio Model(FRM) and spatial analysis function of GIS were applied to produce a predictive distribution map of biota community considering their distribution characteristics according to the environmental factors as related variables. As a result of SMRA, the values of decision coefficient for factors of elevation, stream width, flow velocity, conductivity, temperature and percentage of sand showed higher than 0.5. Therefore these 6 environmental factors were considered as major factors that might affect the distribution characteristics of aquatic insects. Finally, we had calculated RMSE(Root Mean Square Error) between the predicted distribution map and prior survey database from other researches to verify the result of this study. The values of RMSE were calculated from 0.1892 to 0.4242 according to each FFG so we could find out a high reliability of this study. The results of this study might be used to develop a new estimation method for aquatic ecosystem with macro invertebrate community and also be used as preliminary data for conservation and restoration of stream habitats.

• Korean Journal of Environmental Biology
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• v.29 no.4
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• pp.353-361
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• 2011

This study was conducted to examine the effects of sedimentation caused by highland agriculture on benthic macroinvertbrate assemblages in upper Song Stream from 2006 to 2009. The mean concentrations of water quality parameters (pH, DO, EC, TDS, TN, and TP) were gradually increasing toward downstream but ORP was decreased. Furthermore, biological habitats at lower reaches were more homogeneous and unstable due to sand deposition than those at upper sites. A total 106 species of benthic macroinvertbrates in 47 families, 11 orders, 6 classes, and 5 phyla were identified during whole field surveys. Song Stream showed great declines of overall biological attributes along its longitudinal gradients, particularly in taxa richness and abundance. Of all functional groups scrapers and clingers were most affected against the degradation of habitat quality, whereas collector-gatherers and burrowers showed the opposite case. It was found that such results had close correlations with water quality parameters and substrate composition which played an important role in structuring macroinvertebrate communities. In conclusion, this study represents that disturbance caused by highland agricultural activities had negative effects on benthic macroinvertebrate communities by leading to sand deposition at adjacent stream ecosystems.

• Journal of Wetlands Research
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• v.10 no.1
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• pp.39-47
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• 2008

An eco-washland is increasingly getting attentions as a new alternative plan for management of water resources because of role as flooding control and ecological park without social and ecological side effects. However, there is a lack of study regarding technological development and ecological guidelines to create eco-washland. This study was carried out to suggest ecological guidelines necessary for engineering process to create eco-washland. A study site was the lower reach of Seokjang stream connecting to Yimjin river, a candidate of new eco-washland, and Kumsa area in Namhan river was selected as a reference site. The analysis of ecological characteristics focused on vegetation, fishes, and birds. Major vegetation communities, composed of dominant species such as Salix koreensis, Salix gracylistyla, Miscanthus sacchariflorus, Phragmites communis, etc., formed physical conditions along with other land uses including open water, sandbar, cultivated land, etc. Dominant species of fishes were some species belonging to Cyprinidae and Acheilognathinae, and in case of birds Anser albifrons, Anas platyrhychos, Anas poecilorhyncha belonging to waterbirds and Paradoxornis webbinanus dependent to forest edge were dominantly distributed. The results showed that complex wetland types associated with partially deep water and upland was the optimal eco-hydrological condition of washland. Cyprinidae and Acheilognathinae in case of fish and Egretta spp. (spring season) and Anas spp. (winter season) in case of bird were selected as target species for the these wetland types. Finally, a detail planning criteria to create habitats of these target species were discussed in terms of spawning, breeding, feeding, resting, refuge, nesting, etc.

• Korean Journal of Environment and Ecology
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• v.23 no.6
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• pp.553-563
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• 2009

This study was conducted to analyze the changes in the echolocation of Pipistrellus abramus according to environmental characteristics. The survey was conducted in the day-roosting site of P. abramus located in Gyeongju City (North Gyeongsang Province) from April to August, 2009. The environmental characteristics during the research were classified in six categories: the emergence time after sunset moving time from day roost to feeding areas; rice fields; forest edges; open spaces; and residential areas. Analysis results showed that there are differences in environmental characteristics and also differences between the moving time to the habitat and the moving time to capture preys. At the emergence time from day roost, Pipistrellus abramus used a FM signal with a short pulse-duration. In open spaces, however, they used a CF signal with a long pulse-duration. In different environmental situations, they used both FM and CF signals, although the types of pulse which they used were different. Except pulse-duration, there were significant differences in pulse-interval, peak-frequency, starting-frequency and ending-frequency between the movement among habitats and the movement to capture preys. Except the emergence time from day-roost, they showed a narrow band FM signal and a long pulse-duration that are suitable to search for insects by sensing echoes of insects when they moved among their habitats. When they were out to capture their preys, they showed a broad band FM signal and a short pulse-duration which enabled them to widely search and accurately locate their preys.

• Journal of Environmental Impact Assessment
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• v.24 no.4
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• pp.301-316
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• 2015

The endangered species, The Red-crowned Crane and the White-naped Crane are vulnerable species to the disturbance for human beings. We examined the importance of CCZ for the cranes by comparing the crane's density in some CCZ-released areas, which are cranes' wintering site in Cheorwon. We also assessed influence of disturbance such as construction and greenhouses on core habitats of cranes. Our study results suggested that the construction and reclamation in the CCZ shrunk core habitat area while increasing core area of far from the construction and reclamation area. The CCZ has been set since March, 2011 and the number of greenhouse has rapidly increased after 2012. As the number and size of greenhouse in the area where designation of CCZ was cancelled increased, foraging area of cranes diminished. Although the area where designation of CCZ was cancelled seemed to have more human disturbance than CCZ, the foraging density of cranes did not decline and even that of white-naped cranes increased. This could be the influence of artificial food supply at their roosting site. In conclusion, if the area of CCZ decline continuously in the future, density of cranes would decrease.

• Ecology and Resilient Infrastructure
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• v.3 no.1
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• pp.62-69
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• 2016

Narrow-mouth frog (Kaloula borealis) is the only amphibian species of genus Kaloula living in South Korea. They are designated and managed as endangered class II wildlife by the Ministry of Environment, Korea. Therefore, there is a desperate need of a habitat restoration study to prevent the extinction of narrow-mouth frog. This study is primarily for the purpose of presenting the direction and practical applications to restore damaged narrow-mouth frog habitats or to suggest alternative habitat options. The habitat suitability index (HSI) of narrow-mouth frog was applied to the research area in Mokpo City of Jeollanam-do Province, in order to present a new narrow-mouth frog habitat. We analyzed the research area based on historical contexts, ecological environment, ecology, and habitat requirements. The research area was divided into the core, buffer, and transition zones according to UNESCO MAB (Man and Biosphere) to establish local land-use plans. As for the foundation of the plan, we divided the habitat composition of the core, where narrow-mouth frog live in, into wetland (spawning area), grassland (shelter and feeding grounds), and forestland (feeding ground). We had a comparative analysis of habitat suitability in pre and post planning of narrow-mouth frog habitat restoration. For the validation study of habitat restoration plans, the future research should be on the composition of test-bed, continuous monitoring, and scientific habitat maintenance.

• 한국해양학회지
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• v.19 no.2
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• pp.153-162
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• 1984

This study was conducted to interpret the relations between the polychaete community and its environments in Kwangyang Bay during July, 1982. The type of sediments in the study area varies from sand to clay and the organic content obtained by ignition was in the ranges of 0.3% to 15.4%. The polychaetes which occurred at 25 stations comprised 70 species representing 63 genera and had an average density of 490 animals/m$\^$2/. The most abundant species were Lagis bocki (20%), Lumbrineris longifolia (10%), Chohe teres (7%), and Sternaspis scutata (5%). The polychaete populations show the highest density in muddy sand sediments and have a tendency to decrease their abundance in finer sediments such as bud and clay. The individual numbers of each feeding type show the same tendency. Kwangyang Bay consists of three distinct characteristic communities, representing different physical and biological factors: delta community, muddy flat community and channel community. Delta community has very poor organisms and seems to be determined by physical factors such as tidal current, and by sediment conditions and seems to be determined by physical factors such as tidal current, and by sediment conditions and by the food availability. Muddy flat community shows more diverse and higher abundance than delta community but seems to be impoverished by the stress of oxygen deficiency in sediments. Channel community has the highest density in the study area and comprises more various feeding types. This is probably due to the supply of allochthonous materials from the Seomjin River and offshore as food, the heterogeneous sediments and some biological interactions within habitats.

• Korean Journal of Environmental Agriculture
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• v.31 no.4
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• pp.359-367
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• 2012

BACKGROUND: As natural wetlands are decreased by increment of human demand, the importance of rice fields as an alternative habitat for waterbirds is well documented. However, the relationship between waterbirds use and management practice of rice fields has not been fully understood. The present study attempted to understand the changes in temporal abundance of waterbirds and their preference for habitat types in rice fields all year round. METHODS AND RESULTS: Waterbirds census were conducted in rice fields around Asan bay in Korea during April 2009-March 2010 and April 2011-March 2012. In the bird counts, the locations of the observed birds on a 1/2,500 map were recorded along with the local habitat type (paddy, ditch, levee, road). Thirty five species of waterbirds recorded in the rice fields during the survey period and three major groups (shorebirds, herons, and waterfowls) were characterized according to season and micro-habitat use. Shorebirds visited a flooded paddy for feeding during their spring migration season (April-May), and herons used the rice field as feeding sites during their breeding periods (April-October). Most waterfowls were observed in a dry paddy to feed a fallen rice seed and stubs during the winter season (September-March). Waterbird groups selectively used micro-habitats in rice field. Shorebirds and waterfowls mainly preferred at rice paddies, while herons were attracted to most habitat types. CONCLUSION(S): Rice fields supported various waterbirds all year round and waterbird communities using the rice fields were dramatically changed according to seasonal change of rice field condition.

• Korean Journal of Environmental Agriculture
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• v.34 no.3
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• pp.178-185
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• 2015

BACKGROUND: The coexisting shorebirds often use various foraging strategies, including feeding methods and habitat use, which are the likely mechanisms to explain the variation of morphological and behavior traits. We studied the foraging behaviors of four shorebirds to define how species separate according to habitat structures in rice fields of western-central Korea during their northward migration. METHODS AND RESULTS: The studied species were Long-toed Stints (Calidris subminuta), Wood Sandpipers (Tringa glareola), Common Greenshanks (Tringa nebularia), and Black-tailed Godwits (Limosa limosa), which were commonly observed in rice fields and represented by a wide range of morphological traits. Habitats were categorized into three types ("plowed with water", "shallow water level after harrowing", and "deep water level after harrowing") according to the irrigation intensity and soil manipulation of the farming practices. Long-toed Stints mainly foraged in the "plowed with water", where they used both visual and tactile searching methods. Wood Sandpipers and Common Greenshanks were frequently observed in "shallow water level after harrowing" They spent a considerable amount of time using a visual searching method. Black-tailed Godwits were selectively attracted to "deep water level after harrowing" and used tactile cues as their predominant feeding technique. CONCLUSION: This study demonstrates that the water levels related in soil manipulation and irrigation intensity influence the accessibility to foraging sites and the detectability of prey for shorebirds species.

• Ocean and Polar Research
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• v.33 no.1
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• pp.85-97
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• 2011

The tidal flats of Korea today have reduced by 40% in size compared to 1964. To manage this important habitat properly, development of well-organized and nationwide-applicable grading systems is required. There have been several assessment systems proposed previously in Korea, but they are critically flawed in that selected biological indicators are not adequate and grading criteria are obscure and arbitrary. We reviewed the indicators used in these previous evaluation systems (e.g., diversity indices, quantity and quality of benthic macrofauna, halophytes, water birds, etc.) and subsequently proposed new indicators and an improved grading scheme. For the quantitative assessment of macrobenthic community, biomass reflecting production and ecosystem function is recommended over density, which is much less discriminatory among habitats. Of biodiversity indices used, within-, between-habitat and regional biodiversity indices that accurately reflect sampling efforts are suggested. In addition, we proposed to include species rarity, ecosystem engineers, and the ecological quality index ISEP (Inverse function of Shannon-Wiener Evenness Proportion). As for halophytes, their low spatial coverage on benthic habitat suggests that their presence can be used as an ecological indicator of benthic habitat, regardless of their protective status. We stress the need to introduce 1) quantile approach for quantitative indicators (e.g., diversity, biomass, etc.) in relation to grading, 2) presence-absence approach for spatial or aggregate indicators (e.g., boundaries of halophytes and feeding ground of water birds) and 3) benthic habitat mapping that combines all of these indicators.