• Title/Summary/Keyword: Limnology

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Monitoring on Bolboschoenus planiculmis Restoration in Nakdong River Estuary: Implications for Wetland Restoration Using Shoot Transplantation (낙동강하구 새섬매자기(Bolboschoenus planiculmis) 복원 모니터링: 식물체(shoot) 식재를 이용한 습지복원)

  • Gu-Yeon Kim;Hee Sun Park;Hwa Young Kim;Ji-Young Lee
    • Korean Journal of Ecology and Environment
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    • v.55 no.4
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    • pp.406-414
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    • 2022
  • Bolboschoenus planiculmis has been acknowledged as a key species in whooper swans (Cygnus cygnus) habitat by providing food for this migratory waterfowl. B. planiculmis wetlands are being degraded by water shortages and salinization caused by anthropogenic activities and climate changes. In 2004, the distribution of B. planiculmis in the tidal flats of the Nakdong Estuary was 2,475,568 m2, and in 2021, the distribution area was 798,731 m2, which decreased by 32.3%. In order to restore the degraded B. planiculmis wetlands, shoot transplantation and seed sowing were tentatively used in three places with different salinity and water levels. The average density per unit area in September at the optimal growth period after planting were A (fresh water level 50 cm) 58±15.65 m-2, B (brackish water level 0~5 cm) 188±63.83 m-2, C (brackish water level 0 cm or less) 188±45.13 m-2. The tubers were observed as A 0 g dw m-2, B 25.32±2.94 g dw m-2, and C 13.39±0.91 g dw m-2. Tubers were distributed in the soil, with only 3.0% at the 10~20 cm depth but 97.0% at the 0~10 cm depth. In contrast, the germination rate of B. planiculmis seeds was observed to be 0%. Results of this study provide technical support for the restoration of B. planiculmis wetland and the improvement in the quality of whooper swans habitat.

The Monitoring of Eel-ladder in Geumgang Estuary Bank, Yeongam Embankment and Asanman Embankment (금강하굿둑, 영암방조제, 아산만방조제 뱀장어 전용어도 모니터링)

  • Jae Goo Kim;Yun Jeong Cho;Cheol Woo Park;Jong Wook Kim;Yu-Sin Shin;Min-Young Im;Younghee Song;Wonjang Kim;Yoon Choi
    • Korean Journal of Ecology and Environment
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    • v.55 no.2
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    • pp.167-174
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    • 2022
  • The Ministry of Oceans and Fisheries promoted the installation of eel-ladder for the purpose of creating inland water resources. Currently, eel-ladder have been installed and operated at the Geumgang Estuary Bank (2018), Yeongam Embankment (2019), and Asanman Embankment (2020). In this study, the number of glass eels in eel-ladder in 2021 was monitored and factors affecting the rise that from ocean to river of eels were investigated. Glass eels in eel-ladder were found when the salinity was relatively low, and they started when the freshwater and seawater temperatures were above 20℃. Comparing the number of occurrences by year, the largest number of glass eels was observed in 2021, but it is judged that this is not according to the distribution of glass eels in sea, but rather as a result of the investigator's eel-ladder repair and guidance on illegal fishing.

Korea's Strategy for Participating in Arctic Biodiversity International Cooperation Projects (한국의 북극 생물다양성 국제협력사업 참여 전략)

  • Sung-Ryong Kang;Jihyun Yoon;Inyoung Jang
    • Korean Journal of Ecology and Environment
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    • v.55 no.4
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    • pp.390-397
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    • 2022
  • Conservation of Arctic Flora and Fauna (CAFF) is the biodiversity working group of the Arctic Council. CAFF conducts Monitoring, Assessment, Policy, and expert group activities to preserve Arctic biodiversity and ensure the sustainability of biological resources and communicates the results to governments and indigenous peoples. The main tasks of CAFF consist of monitoring (Circumpolar Biodiversity Monitoring Program), assessment (Arctic Biodiversity Assessment) and strategic projects(Arctic Migratory Bird Initiative, AMBI). Korea has been directly participating in the AMBI since 2015 after acquiring observer status of the Arctic Council in 2013. The AMBI aims to preserve habitats on migration routes used by breeding birds in the Arctic and prevent illegal hunting. Thus, observer countries on migratory routes are directly participating in the project. When selecting priorities for participation in Arctic cooperation projects by 2030, Korea should consider continuing participation in AMBI and participating in the "CAFF Youth Program" in connection with the Arctic Academy program operated by Korea's public institutes.

Food Web Models in Aquatic Ecosystems: Review (수생태계 먹이망 모델 고찰)

  • Young-Seuk Park;Kyung Ah Koo
    • Korean Journal of Ecology and Environment
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    • v.55 no.4
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    • pp.259-273
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    • 2022
  • Interactions between species in a community are very complex, and they are visualized and analyzed through a food web in simple way. Food web is a network of species connected by trophic links showing energy flow from prey to predator. Various models were developed to characterize the food web in ecosystems. In this study, we classified food web models to static models such as Ecopath and dynamic models such as AQUATOX. We presented characteristics of several different types of food web models in each category, and reviewed their applications used in aquatic ecosystems. Finally, we presented issues to be considered to develop food web models.

Unreported Taxa in Freshwater and Brackish Blue-green Algae in South Korea (담수와 기수성 남조류의 한국 미기록종)

  • Yong-Jae Kim;Dong-hyun Yi;Hyeon-cheol Hong
    • Korean Journal of Ecology and Environment
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    • v.56 no.1
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    • pp.14-35
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    • 2023
  • Freshwater and brackish blue-green algae were collected at 43 freshwater and brackish sites (including lakes, ponds, swamps, streams, and rivers and estuaries) throughout South Korea from March 2017 to October 2018, and were identified using light microscopy. A total 223 taxa in freshwater and 230 taxa in brackish waters in 2017 and 274 taxa in fresh and brackish waters in 2018 were identified and among them, 20 taxa were unreported taxa of blue-green algae in Korea; The new recorded taxa were Aphanocapsa marina, Calothrix fusca f. durabilis, Calothrix littoralis, Calothrix parva, Chamaesiphon minimus, Chroococcidiopsis cubana, Chroococcidiopsis fissurarum, Coelosphaerium aerugineum, Dolichospermum mendotae, Eucapsis alpine, Gomphosphaeria cordiformis, Gomphosphaeria natans, Merismopedia danubiana, Lynbya aestuarii var. gaditana, Tolypothrix tenuis, Pseudocapsa maritima, Pseudocapsa sphaerica, Pseudophormidium tenue, Trichodesmus sp. and Woronichinia elorantae.

The Application of Zooplankton Assemblage for the Evaluation of Aquatic Environments in Lentic Ecosystems (호소 생태계에서의 수환경 평가를 위한 동물플랑크톤 적용 연구)

  • Hyun-Woo Kim;Yu-Ji Heo;Kyung-Lak Lee
    • Korean Journal of Ecology and Environment
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    • v.56 no.1
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    • pp.83-93
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    • 2023
  • This study compares the abundance and community structure of zooplankton organisms from pelagic regions, and considers particularly the trophic levels vs. zooplankton abundances and biomass. Zooplankton samples were collected three times from May to November 2022, at 30 temperate lakes and reservoirs, which belong to four different river basins. The total zooplankton abundance, biomass and species index were showed considerable spatial variation. The spatial pattern of rotifer abundance was similar to that of total zooplankton abundance, while there were not showed similar patterns of zooplankton biomass (㎍ L-1) in lentic ecosystems. The rotifer strongly dominated the zooplankton assemblage in smaller lentic system than that of larger. A total of 130 species of zooplankton were identified (83 rotifers, 34 cladocerans and 13 copepods). The total average of zooplankton abundance and biomass were 213.7±342.3 Ind. L-1 (n=129) and 1382.8±1850.4 ㎍ L-1, respectively. Total and average of zooplankton abundance were usually dominated by the rotifers (>56.9%), while those of zooplankton biomass were dominated by the cladocerans and copepods (>73.6%) in lentic ecosystems. Considering the Trophic State Index (TSI), the factors of zooplankton abundance and biomass were included in between meso- and eutrophic states(27 lakes, 90% of all). The mean abundance and biomass of zooplankton in eutrophic systems were higher than that of meso- and hypertrophic systems. From this result, we suggest that management strategy for the lentic ecosystem water environment has to be focused more on small-sized lakes and reservoirs, in terms of zooplankton assemblages.

Applicability of Next-Generation Sequencing for Analysis of Stomach Contents in Fish (Next-Generation Sequencing을 활용한 어류 위 내용물 분석의 적용 가능성)

  • Chae-Jin Park;Seonbin Yun;Hyeon-Sik Lee;Seoyun Jang;Kang-Hui Kim;Donghyun Hong;Gea-Jae Joo
    • Korean Journal of Ecology and Environment
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    • v.56 no.1
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    • pp.104-125
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    • 2023
  • The predator-prey interaction in freshwater ecosystems is a crucial area in the ecological study field and one of example to find such interaction is to investigate stomach contents. However, traditional method through visual inspection often induce misidentification, as it depends critically on intactness of physically visible data. In this study, we utilized Next-Generations Sequencing (NGS) technology to test the applicability stomach content analysis and overcome such limitation. NGS was applied to analyze the stomach contents of the Hemibarbus labeo, Tachysurus fulvidraco, and Plecoglossus altivelis collected in the lower part of Nakdong River. As a result, T. fulvidraco had a higher number of Animalia operational taxonomic units (OTUs) intake rate than H. labeo. At the same time, P. altivelis had higher number of Plantae OTUs intake rate than T. fulvidraco and higher Protozoa OTUs intake rate than H. labeo respectively. Therefore, NGS technology application enable to overcome traditional method's limitation and discover hidden interspecific interaction which can further be used in appropriate habitat assessment.

The Relationship between Vegetation (Halophyte Communites) Distribution and Environmental Factors in Estuaries in Korea (한반도 하구에 분포하는 식생(염생식물 군락)과 환경요인 간의 관계)

  • Sung, Nak-Pil;Moon, Jeong-Suk;Kim, Jong-Hak
    • Korean Journal of Ecology and Environment
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    • v.55 no.1
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    • pp.19-34
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    • 2022
  • This study was identified the distribution of vegetation in domestic estuaries and analysed the relationship with environmental fcators based on the health assessment data of the estuary ecosystem surveyed between 2016 and 2018. Of the 325 estuaries surveyed, 187 vegetation communites were investigated in 300 estuaries and 53 halophyte communites accounted for 28.3%. No vegetation distribution was found in the other 25 estuaries. Considering the circulation of estuary, 41 halophyte communites were investigated in open estuaries and 26 halophyte communites in closed estuaries. As a result of canonical correlation analysis (CCA) between the entire distributed vegetation community and environmental factors, salinity (conductivity), T-N, and T-P concentrations were strongly correlated. Among the riverbed material materials of the estuary, the composition ratio of silt, sand, and pebble was the most correlated. Therefor, it is estimated that the distribution location of the halophyte communites were differentiated by being influenced by the sea ares, estuary circulation type, resistance to salinity and riverbed material ratio.

Enhancing Arthropod Pitfall Trapping Efficacy with Quinone Sulfate: A Faunistic Study in Gwangneung Forest

  • Tae-Sung Kwon;Young Kyu Park;Dae-Seong Lee;Da-Yeong Lee;Dong-Won Shim;Su-Jin Kim;Young-Seuk Park
    • Korean Journal of Ecology and Environment
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    • v.56 no.4
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    • pp.303-319
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    • 2023
  • Pitfall traps that use ethylene glycol as a preservative solution are commonly used in arthropod research. However, a recent surge in cases involving damage to these traps by roe deer or wild boars owing to the sweet taste of ethylene glycol has prompted the addition of quinone sulfate, a substance with a pungent taste, to deter such wildlife interference. This study aimed to assess the effects of quinone sulfate on arthropods collected from pitfall traps containing ethylene glycol. We strategically positioned 50 traps using ethylene glycol alone and 50 traps containing a small amount of quinone sulfate mixed with ethylene glycol in a grid pattern for systematic sampling at the Gwangneung Forest long-term ecological research (LTER) site. Traps were collected 10 days later. The results revealed a notable effect on ants when quinone sulfate was introduced. Specifically, it decreased the number of ants. In a species-specific analysis of ants, only Nylanderia flavipes showed a significant decline in response to quinone sulfate, whereas other ant species remained unaffected. Additionally, among the arthropod samples obtained in this survey, we identified species or morpho-species of spiders, beetles, and ants and assessed species diversity. Consequently, the utilization of quinone sulfate should be undertaken judiciously, taking into account the specific species composition and environmental characteristics of the monitoring site. Our study also highlighted the significant response of various arthropod groups to variations in leaf litter depth, underscoring the crucial role of the leaf litter layer in providing sustenance and shelter for ground-foraging arthropods. Furthermore, we have compiled comprehensive species lists of both spiders and ants in Gwangneung forest by amalgamating data from this investigation with findings from previous studies.

Analysis of Stomatal Traits of Non-woody Plant Species Present in a Riparian Park Area in Nakdong River (낙동강 수변 공원 지역에 서식하는 초본 식물의 기공 형질 분석)

  • Myeong-geun Song;Ki-jung Nam
    • Korean Journal of Ecology and Environment
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    • v.56 no.4
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    • pp.384-392
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    • 2023
  • Stomatal pore is an important physiological trait that is closely linked to photosynthesis and transpiration as carbon dioxide and water vapor move through it between the atmosphere and plants. The present study investigated stomatal traits, such as stomatal density, index and size, of herbaceous native and alien plant species living in a riparian park on the Nakdong River to understand how those traits vary and to know if successful settlement of alien plants is attributed to those traits. There was no difference in stomatal density, index and size between native and alien plants with kidney-shaped stomata, suggesting that an empty ecological niche is not an essential prerequisite for the successful settlement of alien plants. Stomatal density showed a negative correlation with leaf thickness and leaf dry weight content (LMDC), but there was no correlation with Specific leaf area (SLA). All plants with kidney-shaped stomata had amphistomatous leaves, and the density and size of dumbell-shaped stomata were lower than those of kidney-shaped stomata.