• Journal of Wetlands Research
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• v.26 no.3
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• pp.285-297
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• 2024

This study, conducted in Geolpo-dong and Gamjeong-dong near Gimpo-Hangang New Town, examines an area adjacent to the Han River estuary, a major wintering ground for migratory birds. Over 59 surveys from October 2015 to March 2022 in four representative rice fields (sites A-D) recorded 44,942 individuals from 32 genera and 72 species. Site D, a large area near the Han River, exhibited high species diversity. Despite lower diversity in areas under development (sites A, B, C), ongoing species influx and utilization persist. The study focuses on Anser fabalis, a species predominantly utilizing rice fields, and identified their distribution characteristics. The analysis revealed 162 instances of population influx, with over a 30-fold increase observed across 39 surveys conducted over a 30-month period (October to March, '15~'22). The area, a key wintering site for migratory birds of Janghang Wetland, about 5 km from feeding sites, is heavily utilized by migratory geese, indicating the region's high value considering migration distance and anticipated continuous bird influx despite urban expansion. Therefore, future developments should preserve ecological corridors and connected stepping stone habitats to not only preserve existing habitats but to secure alternative feeding sites, ensuring smooth movements and mitigating habitat loss.

• Korean Journal of Ecology and Environment
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• v.41 no.2
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• pp.155-165
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• 2008

The purpose of this study was to evaluate the ecosystem of Yeongsan Lake using physical, chemical, and biological indicators. We evaluated the integrative ecosystem health using Lentie Ecosystem Health Assessment (LEHA) model, Qualitative Health Evaluation Index (QHEI) model, and chemical water quality. The models of LEHA and QHEI were modified as 10 and 7 metries attributes, respectively. Also, we analyzed bioaccumulation of total mercury on various fish tissues by method of U.S. EPA 7473 using Direct Mercury Analyzer (Model DMA-80). Model values of LEHA model averaged 19 (range: $14{\sim}26$, n=15), which indicated a "poor" condition, and had slightly spatial variations. Values of the QHEI in the all sites averaged 72, which were judged as a "fair" to "good" condition. The QHEI values varied from 48 (fair condition) to 99 (good condition) and showed large longitudinal gradients between the upper and lower reach. Conductivity and salinity were increased from the up-lake to downlake reach. Analysis of total mercury in fish tissues showed that levels of total Hg ranged between 0.002 and $0.087\;mg\;L^{-1}$ depending on the types of tissues. Overall, the ecosystem health in the Yeongsan Lake was judged as a "poor" and the effects of bioaccumulation on the fish tissues were minor. Therefore, it is necessary to keep an efficient management for the lake environment to maintain their ecological health.

• Proceedings of the Korea Water Resources Association Conference
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• 2022.05a
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• pp.485-485
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• 2022

본 연구에서는 낙동강 수계에서 어류의 수생태 건강성이 악화된 지점, 장기간 수질이 악화되거나 수위가 저하된 지점, 보호종이 지정된 지점을 중심으로 어류 서식지적합도지수(Habitat Suitability index, HSI)를 산정하였다. 현장조사는 하천유량이 감소하는 4월부터 6월 사이 총 4회 실시하였고, 투망과 족대를 이용해 어류 채집하였다. 어류의 서식지 특성 조사를 위해 채집 지점에서 수심, 유속, 하상재료를 조사하고 기록하여 엑셀 자료를 구축하였다. 본 연구에서는 실제 하천 단면의 물리적 특성을 잘 반영할 수 있는 WDFW(Washington Dept. of Fish and Wildlife) 방법을 이용하여 어류 서식처적합도지수를 산정하였다. 낙동강 수계 10개 지점에서 실시한 어류 조사 결과는 전체 9과 35종 2,227개체이다. 낙동강 수계 10개 지점의 대표어종을 선정하기 위해 법정보호종, 유영성종, 고유종, 기타 중요종을 검토한 다음 각 지점별 대표어종, 대리어종, 유사어종 등을 산정하였다. 낙동강 수계 전반에 걸쳐 피라미가 우점종으로 조사되었으며, 낙동강 상류지역에는 모래무지, 하류에는 수수미꾸리와 유사한 종의 출현빈도가 높은 것으로 나타났다. 낙동강 전역에 걸쳐 서식하고 있는 피라미는 가능한 대표어종에서 제외하고, 보호종과 고유종을 중심으로 대표어종을 선정하였다. 그 결과 낙동강 상류 내성천 합류전 지점에서는 피라미, 내성천에서 참마자, 위천에서 참몰개, 갑천에서 돌고기, 황강에서 모래무지, 금호강에서 돌마자, 밀양강에서 쉬리. 남강에서 피라미, 형산강에서 참갈겨니, 태화강에서 피라미로 대표어종을 각각 결정하였다. 다음으로 각 지점별 대표어종에 대한 수심, 유속, 하상재료 조사 자료를 이용해 대표어종에 대한 서식지적합도지수를 산정하였다. 최근 갈수기 유량 감소로 생태계가 위협받는 기간이 증가하고 있다. 하천의 정상적인 생태기능 유지를 위한 최소한의 유량이 필요하고, 이를 확보하기 위한 노력이 요구된다. 어류의 서식지적합도지수를 활용해 갈수기 어류 서식에 필요한 최소한의 유량을 결정하거나, 수생태계 복원을 위한 기초자료로 활용성이 높을 것으로 판단된다.

• Korean Journal of Environmental Biology
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• v.27 no.2
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• pp.155-163
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• 2009

The Oriental white stork (Ciconia boyciana) is an endangered species in Korea as well as in the world. In order to provide information on foraging habitats for releasing storks to the wild, we studied the foraging behavior of the species according to different food densities and water levels. We released two individuals, male and female, after enclosing a study site with a fence and cutting out a part of two or three primary feathers. Research was conducted from 20 June to 16 August 2008 at Whawon-ri, Mewon-myung, Chungcheongbuk-do, South Korea. We investigated habitat patch usage, foraging efficiency, and foraging methods of the feeding individuals in the different food densities and water levels. The storks invested more for foraging time and trials, and they captured more food in a habitat of high food density than others. The female invested more time and captured food most in a habitat of lowest water depth while the male in a habitat of middle water depth. However, foraging efficiency did not differ significantly among habitats of food density and water depth, and only differed between male and female by ways of foraging method. From this study we suggest that the storks select foraging habitats and foraging methods under different conditions of food density and water depth.

• Journal of Environmental Impact Assessment
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• v.31 no.2
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• pp.117-127
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• 2022

The survey of bird community characteristics was carried out four times on 2016 and 2017, respectively May and October to figure out effects of the manmade small ecosystem, Anseong. Twenty five species and 94 individuals were observed in the study area. The dominant species were Passer montanus 19.1%, Pica pica 12.8%, Cyanopica cyana 8.51%, Sinosuthora webbiana and Carduelis sinica ussuriensis respectively 7.45%, the diversity of the species was 2.787. With migration, the highest number and percentage to the lowest was residents 72.0%, summer visitors 20.0% and winter visitors 8.00%. Among 22 species which bred (check or possibility) in the manmade small ecology, Anseong, canopy (C) was 54.5%, hole (H) was 31.8%, bush (B) was 9.09% and ground (G) was 4.55% in their nesting guilds. In foraging guilds in breeding season was canopy (C) was 69.6%, bush (C) was 21.7%, water (W) and ground (G) was respectively 4.35%, and in non-breeding season, canopy was 64.0%, bush 24.0%, ground was 8.00% and water 4.00%. In the study site, the manmade habitats for birds were nest box and wetland (rain garden). In 7 nest box, Parus major was uesd 1 nest box as their breeding on 2016 and 2017, and Passer montanus was used 1 nest box on 2017. We assumed that sustainable rainwater supply may be important to attract many birds in rain garden, the manmade habitat for birds.Unfortunately, however, no birds used rain garden (wetland) as their habitats due to water shortage.

• Korean Journal of Ecology and Environment
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• v.49 no.3
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• pp.197-207
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• 2016

This study aims at providing basic data to objectively evaluate the areas suitable for reintroduction of the species of Asiatic black bear (Ursus thibetanus) in order to effectively preserve the Asiatic black bears in the Korean protection areas including national parks, and for the species restoration success. To this end, this study predicted the potential habitats in East Asia, Southeast Asia and India, where there are the records of Asiatic black bears' appearances using the Maxent model and environmental variables related with climate, topography, road and land use. In addition, this study evaluated the effects of the relevant climate and environmental variables. This study also analyzed inhabitation range area suitable for Asiatic black and geographic change according to future climate change. As for the judgment accuracy of the Maxent model widely utilized for habitat distribution research of wildlife for preservation, AUC value was calculated as 0.893 (sd=0.121). This was useful in predicting Asiatic black bears' potential habitat and evaluate the habitat change characteristics according to future climate change. Compare to the distribution map of Asiatic black bears evaluated by IUCN, Habitat suitability by the Maxent model were regionally diverse in extant areas and low in the extinct areas from IUCN map. This can be the result reflecting the regional difference in the environmental conditions where Asiatic black bears inhabit. As for the environment affecting the potential habitat distribution of Asiatic black bears, inhabitation rate was the highest, according to land coverage type, compared to climate, topography and artificial factors like distance from road. Especially, the area of deciduous broadleaf forest was predicted to be preferred, in comparison with other land coverage types. Annual mean precipitation and the precipitation during the driest period were projected to affect more than temperature's annual range, and the inhabitation possibility was higher, as distance was farther from road. The reason is that Asiatic black bears are conjectured to prefer more stable area without human's intervention, as well as prey resource. The inhabitation range was predicted to be expanded gradually to the southern part of India, China's southeast coast and adjacent inland area, and Vietnam, Laos and Malaysia in the eastern coastal areas of Southeast Asia. The following areas are forecast to be the core areas, where Asiatic black bears can inhabit in the Asian region: Jeonnam, Jeonbuk and Gangwon areas in South Korea, Kyushu, Chugoku, Shikoku, Chubu, Kanto and Tohoku's border area in Japan, and Jiangxi, Zhejiang and Fujian border area in China. This study is expected to be used as basic data for the preservation and efficient management of Asiatic black bear's habitat, artificially introduced individual bear's release area selection, and the management of collision zones with humans.

• Korean Journal of Environment and Ecology
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• v.30 no.6
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• pp.962-969
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• 2016

This study assessed the ecological and behavioral characteristics of the sika deer from April 2012 to August 2016. To obtain basic information on the behavioral patterns of the sika deer (Cervus nippon) including their annual home range, sika deer wearing GPS tracking collars were released into 1,385 locations at a different altitude around where they had been captured in Songnisan. The released individuals were studied through home range analysis. According to our observations, annual home ranges of the sika deer (n=6) is seen to be $2.24{\pm}1.50km^2$ (t=3.648, p<0.05) of MCP 95% for the entire area of home range and $0.46{\pm}0.31km^2$ (t=3.666, p<0.05)$km^2$ of FK 50% for the home range core area respectively. The annual home ranges of the sika deers by sex were $2.94km^2$ for female and $1.53km^2$ for male. This study is expected to provide basic data for habitat management and ecological study of sika deer and to contribute to the management of wild animals.

• Korean Journal of Environmental Biology
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• v.36 no.1
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• pp.21-32
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• 2018

This study was carried out to define the characteristics of the identified ground-dwelling invertebrate communities at Nari basin and Tonggumi area in Ulleungdo Island, designated as a nationally important agricultural heritage. The habitat types were divided into the following categories: crop land, forest, and ecotone, and the soil-dwelling invertebrates were collected according to habitat type. The ground-dwelling invertebrates were collected using a pitfall trap, and a self-organizing map (SOM) was applied to the invertebrates dataset to define the characteristics in invertebrates distribution. The SOM clearly classified the relevant information into four clusters, and extracted ecological information from the invertebrates dataset. The cluster II was composed of invertebrate communities which are collected in the Tonggumi area. The Tonggumi area is where mountainous areas were developed for agricultural purposes, which has geographical features commonly observed in Ulleungdo Island. It is noted that the cluster II has different characteristics as compared other clusters. The results of this study are expected to be used for the preservation of agricultural environment and maintenance of biodiversity by providing basic data, on the biotope of Ulleungdo Island designated as a nationally important agricultural heritage and information on the characteristics of the applicable ground-dwelling invertebrate communities.

• 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.

• Journal of Wetlands Research
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• v.16 no.3
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• pp.355-362
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• 2014

Changes of soil properties due to sedimentation and erosion in the river estuary may lead changes in environmental factors that affect plant growth and distribution, Then habitats in the river estuary that provide various ecological functions can also be influenced. Topsoil samples were analyzed in order to understand the soil properties of important barrier islands and habitat types in the Nakdong river estuary. The samples were obtained from Phragmites communis and Scirpus planiculmis habitats, the tidal flats in the southern area of Eulsukdo, and in Mangeummerydeung, Baekhapdeung, and Doyodeung. Analyses results showed that bulk density, pH, organic matter content and total nitrogen concentration which were directly or indirectly affected by vegetation showed significant difference (p<0.05) with habitat types but no differences in water content and oxidation reduction potential which could be affected by soil texture and showed significant difference among barrier islands. Results suggested that soil properties on barrier islands in the Nakdong river estuary were influenced first by geomorphic changes due to sedimentation and erosion, and then by the presence or type of vegetation. A range of physical and chemical properties were analyzed; soil water content and bulk density (physical properties), and organic content and pH (chemical properties) were correlated with seven other soil properties, at a level of significance higher than 90%. These aspects played an important role in determining overall soil properties in the studied area.