• Journal of Wetlands Research
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• v.24 no.4
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• pp.345-353
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• 2022

A wastewater treatment plant (WWTP) is a major gateway for the engineered nano-particles (ENPs) entering the water bodies. However existing studies have reported that many WWTPs exceed the No Observed Effective Concentration (NOEC) for ENPs in the effluent and thus they need to be designed or operated to more effectively control ENPs. Understanding and predicting ENPs behaviors in the unit and \the whole process of a WWTP should be the key first step to develop strategies for controlling ENPs using a WWTP. This study aims to provide a modeling tool for predicting behaviors and removal efficiencies of ENPs in a WWTP associated with process characteristics and major operating conditions. In the developed model, four unit processes for water treatment (primary clarifier, bioreactor, secondary clarifier, and tertiary treatment unit) were considered. Additionally the model simulates the sludge treatment system as a single process that integrates multiple unit processes including thickeners, digesters, and dewatering units. The simulated ENP was nano-sized TiO₂, (nano-TiO₂) assuming that its behavior in a WWTP is dominated by the attachment with suspendid solids (SS), while dissolution and transformation are insignificant. The attachment mechanism of nano-TiO₂ to SS was incorporated into the model equations using the apparent solid-liquid partition coefficient (Kd) under the equilibrium assumption between solid and liquid phase, and a steady state condition of nano-TiO₂ was assumed. Furthermore, an MS Excel-based user interface was developed to provide user-friendly environment for the nano-TiO₂ removal efficiency calculations. Using the developed model, a preliminary simulation was conducted to examine how the solid retention time (SRT), a major operating variable affects the removal efficiency of nano-TiO₂ particles in a WWTP.

• Journal of Wetlands Research
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• v.24 no.3
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• pp.185-195
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• 2022

This study conducted a survey over spring and autumn from 2014 to 2020 to confirm the ecological characteristics of the size of streams and habitats, centering on the ecological landscape conservation area, and a total 256 species of benthic macroinvertebrates in 105 families, 25 orders, 8 classes, and 5 phyla appeared. In terms of appearance species, by region, the rate of appearance of Ephemeroptera and Trichoptera was high in regions consisting of lotic area and the rate of appearance of Coleoptera and Odonata was high in regions consisting of lentic areas. When comparing the population of Ephemeroptera-Plecoptera-Trichoptera (EPT) groups by region, they were classified into three groups: upstream area, mainstream area, and lentic areas, and it was confirmed that the population ratio of EPT changed as it moved from upstream to downstream. As the stream order increased, the number of species and populations increased. The Shredder group (SH) tended to decrease as the size of stream increased(r=0.9925), and the Collector-Filtering (CF) tended to increase as the size of stream increased(r=0.9319). It was confirmed that the Scraper (SC) replaced each other between species with the same ecological status as it went downstream from upstream, and it is thought that the SC did not differ significantly by stream order. In order to maintain a healthy ecosystem in the designation and management of ecological landscape conservation areas, it is necessary to consider ecological factors such as competition and physico-chemistry factors such as water quality and substrate conditions. Therefore, if the competent authority designated survey areas including buffer areas that include streams and physical habitats of various sizes, it will be advantageous to the conservative area and securing more biological resources.

• Journal of Environmental Policy
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• v.11 no.4
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• pp.3-37
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• 2012

In perspective of biodiversity conservation and protected areas (PAs), the aims of the study are to review the mid-long term national plans, which deal with national territory and environment in Korea, and to find out the way to improve this issue. Key issues were drawn by referring "Biodiversity 2011-2020 Strategic Targets" and "Protected Area Decision" in CBD CoP-10 and 7 National comprehensive or basic Plans were reviewed. Quoting Biodiversity 2011-2020 Strategic Target 5, "By 2020, the rate of loss of all natural habitats, including forests, is at least halved and where feasible brought close to zero, and degradation and fragmentation is significantly reduced", most of national plans included various methods such as "No Net Loss of Green", "No Net Loss of Wetlands", and so on. Regarding the target 11, "By 2020, at least 17% of terrestrial and inland water, and 10% of coastal and marine areas, ecologically representative and well connected systems of PAs and other effective area-based conservation measures, and integrated into the wider landscape and seascapes", 15% by 2015 was set up as a target of total PAs in Korea and 13% by 2015 or 2020 was set up as a target of coastal and marine PAs. CBD CoP-10 Decision X/31 (Protected Areas) invites parties to develop a national long-term action plan for the implementation of PoWPA and describes 10 issues that need greater attention. National action plan for the implementation of PoWPA doesn't be mentioned at any national plans even PoWPA. Regarding the 10 issues, most of issues were well reflected within various national plans, however there is still a need to improve the details and corelation between plans. Particularly, in terms of management effectiveness evaluation (MEE), there was no national plan to directly deal with MEE even though CBD invites parties to work towards assessing 60% of the total PAs by 2015. Based on the review results, below 4 items were suggested; (1)"The Comprehensive Plan of the National Territory" needs more attention on the Biodiversity Conservation and PAs, (2)Consider to establish "National PA System Plan" embedded into "the Comprehensive Plan of National Environment", (3)Establish a "National Action Plan for the implementation of PoWPA", (4)Improve the National Plans through linking with Biodiversity 2011-2020 Strategic Targets and relevant PA key issues.

• Korean Journal of Environment and Ecology
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• v.32 no.6
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• pp.603-617
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• 2018

This study surveyed the diversity and community characteristics of benthic macroinvertebrates and freshwater fish, which are the main animal classifications in a hydro ecosystem, from May to September 2017 in the western plains of the Demilitarized Zone (DMZ). The results showed a total of 125 species of benthic macroinvertebrates belonging to 66 families, 19 orders, and four phyla in the streams and wetlands. Among benthic macroinvertebrates, Coleoptera (27 spp.: 21.60%) was the largest group in terms of species richness followed by Odonata (26 spp.: 20.80%), non-Insecta (22 spp.: 17.60%), and Hemiptera (11 spp.: 8.80%) occupying in the lentic area. Of the feeding function groups (FFGs), predators (51 spp.: 56.67%) showed a relatively larger presence, indicating the dominance of hygrophilous invertebrates that usually inhabit the freshwater wetlands or ponds. Of the habitat oriented groups (HOGs), climbers (33 spp.: 24.44%) and burrowers (17 spp.: 12.59%) were the dominant groups. This observation is typical in a slow flowing habitat and can lead to the disturbance of the ecosystem due to cannibalism among predators. Cannibalism can be caused by stress induced by various population and environmental factors. For the ecosystem services benchmark (ESB) value, site 13 appeared to be the highest with 82 marks while other sites showed relatively lower rates and indices (III water quality class with ${\alpha}$-mesosaprobic). The analysis result of stability factors showed that almost all sites were evaluated to be the I characteristic group with high resilience and resistance or the III characteristic group that was sensitive to environmental disturbance and formed uneven and unstable communities. Of the freshwater fishes, 46 species (3,405 individuals) belonging to 39 families and 18 orders were identified in all the investigated sites. Among them, Cyprinidae (30 spp.: 65.2%) was the largest group, and Zacco koreanus was identified as the dominant species (728 individuals, 21.4%). The survey of freshwater fish communities found both stable communities (sites 7 and 13) with low dominant index (0.39) and high diversity index (2.29) and unstable communities (sites 2, 3, 8, and 10) in opposite tendency. This survey found five Korean endemic species, 17 species belonging to the export controlled species, two endangered species level II (Lethocerus deyrollei and Cybister chinensis), and rare species (Dytiscus marginalis czerskii) among benthic macroinvertebrates. The survey also found an invasive species, Ampullarius insularus, which was distributed throughout the whole area and thus can continuously disturb the ecosystem in the western plain area in the DMZ. Of freshwater fish, one natural monument (Hemibarbus mylodon) and three endangered species level II (Acheilognathus signifer, Gobiobotia macrocephalus, and G. brevibarba) were observed. The survey also found four introduced species (Pomacea canaliculate, Carassius cuvieri, Lepomis macrochirus, Micropterus salmoides) in the western DMZ area, indicating the need for the protection and conservation measures.

• Korean Journal of Environment and Ecology
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• v.36 no.3
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• pp.318-326
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• 2022

The Convention on Biodiversity (CBD) recommends that 17% of the land be designated as a protected area to counter global environmental problems. Korea also realized a need to designate protected areas according to the international level and explain the significance of designating protected areas. Accordingly, studies on ecosystem services are required. In Korea, the protected areas are designated as national parks, provincial parks, and county parks by hierarchy under the Natural Parks Act. However, as priority was on political and administrative aspects, research on ecosystem service value evaluation and habitat management were concentrated in national parks, and provincial and county parks were relatively neglected. Therefore, more studies on provincial and county parks are necessary. In this study, habitat quality for Gajisan Provincial Park, where there were few studies on habitat management and ecosystem service valuation, was evaluated using the InVEST Habitat Quality model among the InVEST models. The analysis results were compared with 16 mountainous national parks. The results showed that the habitat quality value of Gajisan Provincial Park was 0.83, higher than that of the surrounding areas. The analysis of habitat quality in three districts showed 0,84 for the Tongdosa and Naewonsa districts and 0.83 for the Seoknamsa district. By use district, the nature conservation district, the natural environment district, the cultural heritage district, and the park village district had the highest habitat quality value in that order. Compared with the existing habitat quality analysis results of national parks, Gajisan Provincial Park showed naturalness at the level of Mudeungsan National Park. These results can be used as objective data for establishing policies and management plans to preserve biodiversity and promote ecosystem services in provincial parks.

• The Korean Journal of Ecology
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• v.28 no.5
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• pp.335-345
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• 2005

A study on changes on the distribution of vascular hydrophytes and the growth pattern of Schenoplectus triqueter (Scirpus triqueter) was undertaken at the Nakdong River estuary from 2002 to 2004. The change was due to physical alteration of the estuary for the past 25 years. These plant species are the major food sources for winter waterfowl. A total of 32 species of vascular hydrophytes from 17 families were found in the West Nakdong River (freshwater), the main channel of Nakdong River (freshwater) and the Nakdong River Estuary (brackish water). After the construction of the barrage on the estuary in 1987, the number of hydrophytes has remarkably increased to 17 species (5 species in 1985) in the main channel of the River. In particular, a community of Eurale ferox was found at the backwater wetland of the Daejeo side of the main channel. The introduced species of Eichhornia crassipes and Pistia stratiotes that were epidemic in 2001 at West Nakdong River was not found any more. The other species such as Nymphoides indica, Myriophyllum spicatum, Ruppia spp. were rediscovered. The large area (about 1,300ha) of Zostera spp. was the main sources of food for swans, but disappeared because of direct and indirect impacts of reclamation in the River estuary. Currently, there remains a small patch of Zostera spp. and about 250ha of S. triqueter. Schenoplectus triqueter grew mostly between April-September and tuber formed, between September-October. The growth of S. triqueter up to $60\sim80cm$ in length was observed in 5 sites out of the 7 sites in brackish area. Tubers of S. triqueter were eaten by waterfowls such as swans as winter food. In five sites, tubers took $44\sim57%$ of total biomass in October. Tubers were found in deep layers; $5\sim15cm$ (9%), $15\sim25cm$ (28%), $25\sim40cm$ (55%), below 40cm $(6\sim7%)$. The distribution of vascular hydrophytes has remarkably changed in the Nakdong River Estuary due to the reclamation of the area. In order to determine the extent of changes of the distribution of these plants and the carrying capacity of the area for waterfowl, an intensive research is urgently needed.

• 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.

• Korean Journal of Ecology and Environment
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• v.50 no.4
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• pp.422-431
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• 2017

The biogeochemical information of riverine organic matter gives a detailed and integrated recording of natural and anthropogenic activity within a watershed. To investigate the changes in quality and quantity of organic carbon transporting from mountain to ocean via river channels, we estimated the concentrations of dissolved (DOC) and particulate organic carbon (POC), and then traced the source origin of POC using stable carbon isotopes ratio before and after summer rainfalls in the Tamjin River and Ganjin Bay, Korea. Along the small watershed, a total of 13 sites including headwaters, dam reservoir, river and estuary were established for the study. We found some interesting findings in the aspect of distribution of DOC/POC concentration changing their origin sources dynamically flowing downstream. In particular, the river channel transport downstream mainly DOC to river mouth, although upper dam reservoir increased POC concentration by phytoplankton production in summer. Whereas, in the river mouth and estuary, POC was dominated not only by local supply from nearby reed saltmarsh, but also by marine phytoplankton production, respectively. The findings can contribute to increasing the understanding of riverine organic carbon transport in upper large dam and lower open estuary system.

• Korean Journal of Environmental Biology
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• v.38 no.3
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• pp.371-387
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• 2020

This study was conducted to investigate the flora of Mt. Unbongsan in the basalt areas of Korea. From the results of eight field surveys undertaken from March to October 2017, we identified 404 total taxa, representing 364 species, seven subspecies, and 33 varieties, which were placed in 256 genera and 91 families. The plant formation of Mt. Unbongsan is a deciduous broad-leaved and conifer mixed forest, which is common in the middle part of the Korean peninsula. Most of the mountain is covered by a young secondary forest, which is mainly composed of Quercus monglica and Pinus densiflora. Out of these 404 taxa, 193 were the first records for the region, six were endemic to Korea, three were listed on the Korean Red List of threatened species, 34 were floristic target species, and 40 were invasive alien species. The naturalized index(NI) percentage was 9.9%. Mt. Unbongsan has plant diversity, which was associated with the geomorphological landscapes. We considered that the composition and distribution of the species were affected by different environmental factors according to the presence of granite, taluses, block streams, drying ridges, valleys, puddles, wetlands, and streams.

• The Journal of the Korea Contents Association
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• v.19 no.10
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• pp.607-619
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• 2019

This study used Natural Monument water spiders and their habitats as educational contents, so those students could have a scientific literacy and the beautiful memories of Eundaeri's marshes through developing a virtual fieldwork courses (VFC) and observing the ecology of water spiders. In order to develop the program, the 2015 revised national curriculum and its textbooks were analyzed. In accordance with the STEAM model, we developed teaching-learning materials for 7 classes. Students produced 3D panorama virtual fieldwork courses (PVFC) about water spider by team-based cooperative learning, enabling them to emotionally experience the meaning and value of water spiders. A panel of six education experts verified the validity of the program and found it to be fairly valid at 4.24 (CVI = .88) on the 5-point Likert scale. In order to confirm the suitability of the program, students in the middle school science clubs participated in pilot testing camp. Their average classes satisfaction was 4.24 and students were very satisfied with the usefulness of the program, the fresh learning contents, and the suitability of the convergence education class. This study could contribute to convergence education related to ecology and virtual reality for adolescents.