• Journal of Wetlands Research
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• v.19 no.1
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• pp.172-179
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• 2017

The purpose of this study is to analyze the current original habitat and to conserve the narrow-mouthed toad populations. For this study, we used 240 pitfall traps (30 cm height ${\times}$ 20 cm width) to catch the narrow-mouthed toads that inhabit in Myeongji-dong, Gangseo-gu, in Busan metropolitan city from August 2, 2013 to November 7, 2013. We measured the environmental characteristics (soil composition factors, soil moisture, Humidity, soil temperature) for the seven habitat patterns of narrow-mouthed toads based on vegetation types. Main habitats of narrow mouthed toads were flat grassland where grass and false acacia grew and there was wetland all over the place. When analyzing habitats that main habitats of narrow-mouthed toads prefer after selecting representative seven vegetation, it was found that the most narrow-mouthed toads were caught in amur silver grass colony while the least narrow-mouthed toads were caught in bare land. Totally, we caught 846 narrow-mouthed toads over 68 times, and released them into the newly constructed habitat after injection VIE-tag. It seems that the reason for which the least narrow mouthed toads were caught in bare land is that bare land is not suitable for narrow mouthed toads to protect themselves from strong sunlight and to hide themselves from natural enemy. We found that temperature had the greatest influence on activities of narrow mouthed toads and at temperature of less than $15.6^{\circ}C$. We also found that the activities of narrow mouthed toads were remarkably low and then temperature was below $15.6^{\circ}C$. It meant that narrow mouthed toads seemed to go into hibernation. From this research, we could find the prefer habitat after analyzing habitats for the narrow-mouthed toads and could suggest for construction for the better habitat of narrow-mouthed toads.

• Korean Journal of Ecology and Environment
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• v.42 no.3
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• pp.340-349
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• 2009

The natural type section of Gap Stream was divided into 7 sites, such as, closed pool, runs, riffle, opened pool, pool, reek-scattered riffle, and Dam-type pool. The ecological characteristics of fish community at each site was examined from April, 2007 to October, 2008. During the survey period, 29 species belonging to 8 families were collected, and Carassius auratus (St. 1), Coreoleuciscus splendidus (St. 3), Acheilognathus lanceolatus (St. 4) and Zacco platypus (St. 2, 5, 6, 7) were characteristic species that represent each habitat. The species of C. auratus preferred physical habitat with sand-bottom pool, moderate depth of 65$\sim$90 cm, and stagnant water. The species of C. splendidus mainly preferred physical habitat with cobbles and pebbles are scattered riffles (St. 3), moderate depth of 65$\sim$90 cm, and flow velocity is 0.14$\sim$0.85 m $sec^{-1}$. It also preferred where concentration of BOD, COD, TN, TP and SS is low and DO's value is high, because the flow velocity is fast. A. lanceolatus preferred where the depth of water is low (3$\sim$44 cm) like an opened pool (St. 4) and the flow velocity is slow (0.01$\sim$0.02 m $sec^{-1}$). Z. platypus dominated in a variety of habitats such as runs (St. 2), pool (St. 5), rock-scattered riffles (St. 6) and D-type pool (St. 7), and it preferred places where flow is abundant and riverbed structure is diverse. On the other hand, 4 individuals of Iksookimia choii appeared at reek-scattered riffles (St. 6). I. choii appeared in this research lived in where the width of river is 24 m, the depth of water is 3$\sim$35 cm and the flow velocity is 0.01$\sim$0.49 m $sec^{-1}$, and riverbed structure was diversely formed with boulder to sand. Also, water temperature, EC, BOD, COD, TN and TP was low, but concentrations of DO and SS were high comparatively. Therefore, it seems that I. choii can live only in physical and chemical environment with similar conditions.

• Korean Journal of Ecology and Environment
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• v.56 no.4
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• pp.375-383
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• 2023

To determine the cause of the population decline in Gobiobotia naktongensis, substrate preference and burying behaviour were investigated in this study. In general, the species was shown to prefer a substrate size of 1 mm or less, depending on the flow. In addition, the burying depth varied according to the size of the fish and increased with a decrease in water temperature. Our findings showed that the main cause of the population reduction was the physical changes in the substrate structure due to the dams or barrages construction. Notably, the accumulation of silt and mud in the substrate upon the formation of an upstream lentic water region for structural construction and bed armouring caused by scouring and reduced downstream inflow of fine sediment were deterministic in the fish habitat changes, causing problems in burying. As sand substrate structure is critical for the survival and inhabitation of psammophilous species, efficient strategies should be developed with proper habitat management to reduce the anthropogenic damage

• Korean Journal of Ecology and Environment
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• v.49 no.1
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• pp.11-21
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• 2016

Cymbidium kanran Makino is being threatened in its own habitats due illegal collecting and habitat changes by vegetation growth along historical landuse change. In this study, we established habitat restoration model for conservation of C. kanran based on ecological diagnosis. Through exploration to Jeju Island in 2014 and 2015, we identified 27 unknown habitats of C. kanran and in there, abiotic variables and vegetation structure and composition were quantified. Altitudinal distribution of C. kanran was between 200 m~700 m a.s.l. and compared to distribution in 2004, Area of Occupation (AOO) decreased at 82%. Specific habitat affinity was not observed by evenly found in mountain slope and valley and summergreen and evergreen broadleaved forests, but likely more abundant in valley habitats with higher soil and ambient moisture. Total of 96 individual of C. kanran was observed with an average density of $942.6individuals\;ha^{-1}$. The plants showed relatively short leaf length (average=$10.7cm{\pm}1.1cm$) and small number of pseudo bulbs ($1.2{\pm}0.2$). Flowering and fruiting individuals were not observed in field. C. kanran was classified into endangered plant species as CR (Critically Endangered) category by IUCN criteria. Phenotypic plasticity of C. kanran was likely support to sustain in more shaded habitat environment and recent habatat changes to closed canopy and low light availability may exhibit negatively effects to C. kanran's life history. Restoring C. kanran habitat should create open environment as grassland and low woody species density.

• Korean Journal of Ecology and Environment
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• v.41 no.3
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• pp.301-310
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• 2008

This study was to analyze characteristics of fish compositions and longitudinal distribution, based on trophic and tolerance guild at 22 sampling sites of Yeongsan River watershed during 2003$\sim$2006, and also to compare before and after the estuary dam construction. The collected fishes, based on catch per unit effort (CPUE), were 44 species in the watershed and dominant fishes were Zacco platypus, Acheilognathus macropeterus, Zacco temminckii and Carassius auratus. According to comparative analysis of fish in the non polluted sites (NPS) vs. polluted sites (PS), the number of species and individuals was lower by 70% in the PS than the NPS, indicating ecological degradations by chemical pollutions or/and habitat modifications. The relative abundance of sensitive and insectivore species decreased as the stream order increases, while tolerant and omnivore species increased with the stream order. In this survey, largemouth bass (Micropterus salmoides), which is a top-carnivore and exotic species, may influence trophic guild system throughout active predations on endemic species, resulting in modifications of ecological functions. The construction of estuary dam on Yeongsan River in 1981 resulted in wider lacustrine zone and desalinated through limitation of seawater input. These physical changes have caused increases of lentic dwelling species and limited fish migrations (i.e., eel). Overall, fish fauna and composition analyses showed that the number of species and individuals in this water body may be reduced due to inputs of pollutants from the watershed, habitat modifications, and increases of exotic species (largemouth bass). For these reasons, effective lake management strategies are required for the ecosystem conservation.

• Journal of Korean Society of Disaster and Security
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• v.11 no.1
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• pp.7-14
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• 2018

The Benangkimi wetland, which serves as a stopover place for migratory birds in the Dadohae Marine National Park in Wando-gun, Jeollanam-do, is a place where various species and a large number of migratory birds are observed. In order to provide an effective and scientific management plan for the habitat environment of migratory birds, we carried out field survey of Benangkimi wetland. The field survey and survey on habitat use of migratory birds were conducted in parallel to obtain the basic data of hydraulics and hydrology. The hydraulic and hydrological survey of Benangkimi wetland was conducted 1-2 times a year during the period of 2015-2016 (two years). It was classified into 4 sectors according to the topography and geology, rainfall, hydraulic characteristics, and wetland conditions. The 3 sectors same as the migratory birds survey sector and the 1 sector as the inflow of the wetland were analyzed. The survey also focused on small migratory birds arriving at Benangkimi wetland during the spring and autumn season. As a result of investigating the population and species in each section, the habitat environment was different according to the water depth, sediment thickness and salinity. Migratory birds prefer hydraulic and hydrological characteristics. This study will be used for the scientific management of Benangkimi wetland, which serves as a stopping point for migratory birds, and it will contribute to basic data of ecology - hydraulics by examining the relationship between habitat environment and hydrological data.

• Korean Journal of Environmental Biology
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• v.31 no.4
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• pp.419-428
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• 2013

The objectives of this research were to determine ecological characteristics and chemical gradients in two different loach populations-Misgurnus anguillicaudatus ($M_a$) and Koreocobitis rotundicaudata ($K_r$). Eight chemical parameters were compared to test the chemical preferences between the two species. The population of Kr occurred more in better water quality, compared to the $M_a$-population. The $M_a$-population co-occurred more with tolerant species (TS) and omnivores, whereas the $K_r$-population co-occurred more with sensitive species (SS) and insectivores. The differences in the tolerance and trophic composition matched well with the result of stream health assessment, based on the multi-metric model of Index of Biological Integrity (IBI). The IBI value in habitat with the $M_a$-population was "19.6" (range: 8~40) indicating a fair condition, and the IBI values of $K_r$-population was 29.4 (range: 12~40) indicating good condition. Similar results were found in physical habitat health analysis (QHEI). Overall, data analysis showed that the $M_a$-population belong to the tolerant species and $K_r$-population belong to sensitive species in the tolerance classification.

• Journal of Wetlands Research
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• v.26 no.1
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• pp.21-31
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• 2024

Macromia daimoji Okumura, 1949 was designated as an endangered species and also categorized as Class II Endangered wildlife on the International Union for Conservation of Nature (IUCN) Red List in Korea. The spatial distribution of this species ranged within a region delimited by northern latitude from Sacheon-si(35.1°) to Yeoncheon-gun(38.0°) and eastern longitude from Yeoncheon-gun(126.8°) to Yangsan-si(128.9°). They generally prefer microhabitats such as slowly flowing littoral zones of streams, alluvial stream islands and temporarily formed puddles in the sand-based lowland streams. The objectives of this study were to analyze the similarity of benthic macroinvertebrate communities in M. daimoji habitats, to predict the current potential distribution patterns as well as the changes of distribution ranges under global climate change circumstances. Data was collected both from the Global Biodiversity Information Facility (GBIF) and by field surveys from April 2009 to September 2022. We adopted MaxEnt model to predict the current and future potential distribution for M. daimoji using downloaded 19 variables from the WorldClim database. The differences of benthic macroinvertebrate assemblages in the mainstream of Nakdonggang were smaller than those in its tributaries and the other streams, based on the surrounding environments and stream sizes. MaxEnt model presented that potential distribution displayed high inhabiting probability in Nakdonggang and its tributaries. Applying to the future scenarios by Intergovernmental Panel on Climate Change (IPCC), SSP1 scenario was predicted to expand in a wide area and SSP5 scenario in a narrow area, comparing with current potential distribution. M. daimoji is not only directly threatened by physical disturbances (e.g. river development activities) but also vulnerable to rapidly changing climate circumstances. Therefore, it is necessary to monitor the habitat environments and establish conservation strategies for preserving population of M. daimoji.

• Korean Journal of Environmental Biology
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• v.39 no.1
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• pp.108-118
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• 2021

The purpose of this study was to provide baseline ecological data for the conservation of the Manchurian trout habitat through the investigation of the growth status of Brachymystax lenok tsinlingensis, and Pearson's correlation analysis (PCA) between the B. lenok tsinlingensis population and the use of the land around Gyebangcheon stream. Sampling was conducted twice in July, September, and October 2018. During the July and September surveys, 882 individuals belonging to 13 species from six families were collected. The dominant species was Rhynchocypris kumgangensis and the subdominant species was Zacco koreanus. The total number of B. lenok tsinlingensis collected was 99. The results of the length-weight relationship in the B. lenok tsinlingensis population were analyzed with a regression coefficient b value of 3.1272 and a condition factor (k) value of 0.0006. Therefore, the growth condition of B. lenok tsinlingensis was regarded as fairly good. The QHEI(Qualitative habitat evaluation index) value in the B. lenok tsinlingensis habitat was 119.5(±0.5)-153.5(±0.5), indicating optimal-suboptimal conditions. As a result of the HIS (Habitat suitability index) analysis, it was confirmed that the optimal habitat for B. lenok tsinlingensis was 0.45-0.55m and >1 m in water depth, 0.55-0.65 m s^-1 in water velocity, and boulder in the substrate. The ratio of the land use in this study site was analyzed as 66.26-96.31% for forest and grassland areas, 0.00-23.79% for agricultural areas, 0.00-4.19% for urbanized areas, and 3.69-8.87% for others. Correlation analysis of the number of B. lenok tsinlingensis and various factors revealed statistically significant correlations between QHEI and forest and grassland areas, agricultural areas, and urbanized areas.

• Korean Journal of Environmental Biology
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• v.33 no.3
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• pp.338-344
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• 2015

In an effort to restore the amphibians in urban freshwater system the characteristics of feeding activity of Rana rugosa living in Gyeonggi-provinces (Yangpyeong-gun and Namyangju-si) was analyzed from 2013 to 2014. The stomach contents of R. rugosa was analyzed non-invasively and compared to organisms captured by sweeping and trapping in their habitat. As a result, Hymenoptera and Cleoptera were primarily preyed by R. rugosa. Particularly, the proportion of Formicidae was more than 98% among the preyed Hymenoptera. Trapped insects in the habitat of R. rugosa's in Namyangju were Hymenoptera (58%, Formicidae 99%), Collembola (17%), Orthoptera (10%) and Diptera (9%) in order in order. In Yangpyeong, trapped insects were Collembola (49%), Orthoptera (14%), Arachnida (9%), Diptera (9%), Cleoptera (7%) and Hymenoptera (3%). Even though Hemiptera and Diptera species are abundant in the streamside zones, R. rugosa could easily hunt Formicidae or Coleoptera on rocks or grassland at streamside. R. rugosa consume small sized ground-insects that are easily found rather than searching for the specific prey. Prey resource of urban stream may be not a limiting factor of R. rugosa inhabitation.