• Title/Summary/Keyword: Natural habitat

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Distribution of Benthic Macrofauna in subtidal area and on sand flat of Sindu-ri coast, Korea (신두리 해안의 조하대와 모래 갯벌에 서식하는 대형저서동물의 분포)

  • Koo, Bon Joo;Shin, Sang Ho;Woo, Han Jun
    • Journal of Wetlands Research
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    • v.7 no.2
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    • pp.69-88
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    • 2005
  • Distribution of benthic macrofauna was surveyed in the subtidal area and on the sand flat of Sindu-ri coast during July 2002. A total of 134 species, 3,511 individuals and 388g biomass of macrobenthos were sampled inclusively from the study sites. 109 species with a mean density of $1,298ind./m^2$ and biomass of $69.4g/m^2$ were collected from 10 stations established in the subtidal area. Polychaetes were represented as a dominant faunal group of the subtidal area in both species richness and density with values of 54 species and $813ind./m^2$. Cluster analysis based on the faunal composition showed that the subtidal area could be divided into four stational groups according to sedimentary characteristics: Cirrophorus armatus - Lumbrineris longifolia association on the mud sediment with pebbles near aqua-farms; Aonides oxycephala association on the rocky bed; Scoloplos armiger - Grandifoxus cuspis association on the sand-dominated sediment along the lowest low water; a association with higher evenness on the sand-dominated sediment in the depth. Although having characteristics of high value in species richness, density and species diversity, the macrobenthic association around the farming area was dominated by the opportunistic species such as Lumbrineris longifolia and Tharyx sp. Natural community represented by S. armiger and G. cuspis was developed in most sand-dominated areas. 50 species were sampled with a mean density of $2,443ind./m^2$ and biomass of $381.3g/m^2$ from eight+ stations along two transects on Sindu-ri sand flat. Mollusks were represented as a dominant faunal group of the sand flat in species richness, density and biomass with values of 20 species, $1,345ind./m^2$ and $350.4g/m^2$, respectively. Umbonium thomasi, Veneridae sp., Mandibulophoxus mai, Armandia lanceolata, Eohaustorius spinigerus, Urothoe convexa were dominant species and these species accounted for over 83% of total individuals. There were three distinct zones of macrobenthos on Sindu-ri sand flat according to the extent of exposure time. The upper zone was dominated by Scopimera globosa, the middle zone was characterized by M. mai, and the lower zone was dominated by E. spinigerus. Sindu-ri coastal area was considered as a healthy habitat for macrobenthos, except for around the farming area. It was considered that Sindu-ri coastal area including the sand flat connected to the sand dune of natural monument was a valuable habitat as a protected site in having no pollution source and no artificial structure.

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A Study on the Ecosystem Services Value Assessment According to City Development: In Case of the Busan Eco-Delta City Development (도시개발에 따른 생태계서비스 가치 평가 연구: 부산 에코델타시티 사업을 대상으로)

  • Choi, Jiyoung;Lee, Youngsoo;Lee, Sangdon
    • Journal of Environmental Impact Assessment
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    • v.28 no.5
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    • pp.427-439
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    • 2019
  • Natural environmental ecology ofthe environmental impact assessment(EIA)is very much lacking in quantitative evaluation. Thus, this study attempted to evaluate quantitative assessment for ecosystem service in the site of Eco-delta project in Busan. As a part of climate change adaptation, this study evaluated and compared with the value for carbon fixation and habitat quality using the InVEST model before and after development with three alternatives of land-use change. Carbon fixation showed 216,674.48 Mg of C (year 2000), and 203,474.25 Mg of C (year 2015)reducing about 6.1%, and in the future of year 2030 the value was dropped to 120,490.84 Mg of C which is 40% lower than year 2015. Alternative 3 of land use planning was the best in terms of carbon fixation showing 6,811.31 Mg of C. Habitat quality also changed from 0.57 (year 2000), 0.35 (year 2015), and 0.21 (year 2030) with continued degradation as development goes further. Alternative 3 also was the highest with 0.21(Alternative 1 : 0.20, Alternative 2 : 0.18). In conclusion,this study illustrated that quantitative method forland use change in the process of EIA can helpdecision making for stakeholders anddevelopers with serving the best scenario forlow impact of carbon. Also it can help better for land use plan, greenhouse gas and natural environmental assets in EIA. This study could be able to use in the environmental policy with numerical data of ecosystem and prediction. Supplemented with detailed analysis and accessibility of basic data, this method will make it possible for wide application in the ecosystem evaluation.

The Vegetation Structure and Management Solution of the Natural Monument (No.374) Pyeongdae-ri Torreya nucifera forest of Jeju (천연기념물 제374호 제주 평대리 비자나무 숲의 식생구조 및 관리방안)

  • Lee, Won-Ho;Oh, Hae-Sung
    • Journal of the Korean Institute of Traditional Landscape Architecture
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    • v.31 no.3
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    • pp.54-60
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    • 2013
  • This study carried out a phytosociological research by Z.-M. school's method describing vegetation structure and management solution about nutmeg tree's(Torreya nucifera ) forests. The nutmeg tree's forests have developed intervale and hills in warm-temperate evergreen broad-leaved forests zone. The nutmeg tree's forests composed 50 familly, 80 genus, 88 species divided two syntaxa(typical sub-community, Arachniodes aristata sub-community) by species composition and correspond to habitat condition. The nutmeg tree's forests show a uniform forest's structure which composed 3~4 layer of sub-tree and shrub. And it was worthy of special mention which characterized diagnostic species of Camellietea japonicae in the warm-temperate evergreen broad-leaved forests. In case of forests floor, were a high rate in order of Ophiopogon japonicus, Polystichum tripteron, Arisaema ringens. And Oplismenus undulatifolius which represent mantle communities as well. This indicates that the nutmeg tree's forests are exposed by humman effects sustainedly. The nutmeg tree's young trees appeared a high rate at half shade and shade. The vigorous tree species have to spacing cutting instead of the heavy thinning that consist in with a shout of declining astructur and function of the forest ecosystem for maintaining a nutmeg tree's forests. And we suggest for the density regulation of the sub-tree and shrub. In conclusion, need to the continuous monitoring about the vegetation structure and management solution for the sustainable nutmeg tree's forests.

Water Chemistry Characteristics and Fish Fauna of Sodo Stream Watershed in Taebaeksan Provincial Park (태백산 도립공원 내 소도천 수계의 이·화학적 수질 특성 및 어류상)

  • Han, Jeong-Ho;Paek, Woon Kee
    • Korean Journal of Environment and Ecology
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    • v.30 no.1
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    • pp.71-80
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    • 2016
  • The fauna of freshwater fish and water chemistry characteristics were investigated from June, 2014 to October, 2014 at 10 sites in Taebaeksan Provincial Park. A total of 7 species under three families were collected from the survey sites and among them one endangered species - Koreocobitis naktongensis - was identified. The endemic species of Korea were 2 species: Koreocobitis naktongensis, Iksookimia koreensis. Dominant species was Rhynchocypris oxycephalus(89%) and subdominant species was Orthrias nudus(8.9%). Water quality including conductivity, turbidity, pH and total dissolved solids(TDS) varied largely depending on the sampling locations. Values of ambient conductivity and TDS were greater in the upstream than in the downstream, and seasonal variabilities were also higher in the upstream. The pH decreased towards the downstream, and especially showed a sharp decrease in S5. This phenomenon was evident due to a dilution by the influx in the acid mine drainage(AMD) of S4. Physical habit conditions, based on qualitative habitat evaluation index(QHEI) model, indicated a "Sub-optimal" condition(mean: 157.3; range: 78 ~ 194) in the Sodo stream watersheds.

Variability in group size and daily activity budget of family groups of the gelada baboon (Theropithecus gelada) at Guassa Community Conservation Area, Central Ethiopia

  • Mamo, Mandefero;Wube, Tilaye
    • Journal of Ecology and Environment
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    • v.43 no.2
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    • pp.263-270
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    • 2019
  • Background: The gelada baboon, Theropithecus gelada Ruppell, 1835, is an endemic primate of the central and western highlands of Ethiopia occurring between altitudes of 1800-4400 m. Variability in activity time budget between the two gelada social units, i.e., one-male units (OMUs) and all-male units (AMUs), has not been studied previously. Thus, the present study was an effort to understand intra- and inter-variations in group size and daily activity time budget in gelada baboon OMUs and AMUs at Guassa Community Conservation Area, Central Ethiopia. The instantaneous sampling method was used in the data collection. Results: Both OMU and AMU groups allocated more time for feeding (OMUs = 36.96%; AMUs = 35%) followed by moving (OMU = 25.8%; AMUs = 27%). Grooming was the most frequent social activity in both family groups (OMUs = 8.56%; AMUs = 11.81%). OMUs and AMUs did not show significant variation between themselves in the time budget and temporal distribution of their daily activities. However, the overall variation in the time budget allocated for daily activities within OMUs and AMUs was statistically significant (p < 0.05%). The different age and sex groups in OMUs (i.e., immature, sub-adult females, subordinate males, adult females, and alpha males) showed statistically significant variation in their time budget allocation for the daily activities (p < 0.05) except for feeding and moving. Alpha males had the highest proportion of resting (32.14%) and aggression (31.92%). Immature individuals were responsible for > 90% of the time budget recorded for playing while adult females showed the highest frequency of grooming. Group size of OMUs ranged between 5 and 15 individuals (mean ± SD = 11.25 ± 1.95). Adult females comprised the highest number within OMUs (mean = 4.5) followed by immature individuals (mean = 3). The group size of AMUs ranged from 4 to 8 (mean ± SD = 6.6 ± 1.5). Conclusion: Our results showed that the gelada baboon spent less time on foraging compared to previous studies at the Simien Mountains and Debre-Libanos area. We suggested this variation could be explained based on higher forage quality at Guassa Community Conservation Area resulting from better conservation of the habitat.

Analysis on the Important Environmental Factors for Reproduction of Trachemys scripta elegans in Jeju Island, South Korea (제주도에 서식하는 붉은귀거북(Trachemys scripta elegans) 번식에 중요한 환경적인 요소 분석)

  • Koo, Kyo Soung;Sung, Ha-Cheol
    • Korean Journal of Ecology and Environment
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    • v.52 no.4
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    • pp.378-384
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    • 2019
  • Red-eared slider, Trachemys scripta elegans, is one of the most famous species to disturb native ecosystems in the world. In South Korea, the species was imported as pet, and now it is found whole of the country. Recent, natural breeding and spreading of the turtle has been reported. In this paper, we investigated the environmental factors to affect the reproduction of T. s. elegans. We surveyed the distribution of the turtle in Jeju island, South Korea, between 2012 to 2017. We compared the land covers and climate of habitats from breeding sites and non-breeding sites. The species was found from 38 sites in Jeju island; 21 of breeding sites and 17 of non-breeding sites. The number of total and only adult turtles was significantly higher in breeding sites than non-breeding sites (P<0.05). In breeding site, the reproduction rate from the farmland was significantly higher than others(P<0.05). However, the rate of land covers was not significant in non-breeding site (P>0.05). The difference on the climate between breeding and non-breeding was not significant(P>0.05). Moreover, none of climate factors affected to reproduction of T. s. elegans(P>0.05). Our study showed that the land covers surrounding the habitats are more important than climate for reproduction of T. s. elegans in Jeju island. This result indicates investigating the habitat and surrounding is necessary for the control of reproduction and spreading of the introduced species.

Horizontal Gene Transfer among Bacteria by Transformation in Soil and Aquatic Environments (토양 및 수계환경에서 Transformation에 의한 세균들간의 수평적 유전물질 전이)

  • 이건형
    • Korean Journal of Environmental Biology
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    • v.18 no.2
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    • pp.205-213
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    • 2000
  • Laboratory studies have revealed that naturally transformable bacteria develop competence under in situ conditions. Thus, the occurrence of competent bacteria in the environment can be considered as a certainty The persistence of free DNA in natural habitats is influenced by nucleolytic degradation and protection from degradation by adsorption to minerals. Although DNA seeded into natural environment was hydrolysed at substantial rates, but was still detectable at low levels after even several weeks. Compared to the number of laboratory based studies, only a few data have been published dealing with transformation of bacteria in the field. Recently, the potential transfer of recombinant DNA (rDNA) from deliberately or accidentally released bacteria to indigenous microbes has raised biosafety issues, since the persistence of rDNA becomes independent of the survival of its original host and leads to unpredictable, long-term ecological effects. The aim of the present review is to summarise recent literature on horizontal gene transfer (HGT) by transformation among bacteria in both soil and aquatic habitat and special emphasis is placed on recent reports which have addressed HGT among bacteria in the field. [Transformation, Horizontal gene transfer (HGT), recombinant DNA (rDNA), Genetically modified microorganisms (GMMs), Biosafety]

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STUDIES ON THE MORTALITY OF THE YOUNG BIVALVES, MERETRIX LUSORIA (1) Boring Rates of Drills on the Young Bivalve, Meretrix lusoria (대합 Meretrix lusoria 치패의 폐사에 관한 연구 (1) 대합치패의 천공복족류 Neverita didyma, Natica severa에 의한 천공률에 관하여)

  • LEE Jung Jae
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.2 no.1
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    • pp.63-70
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    • 1969
  • 1. This paper deals with the natural mortality of the early young bivalve, Meretrix lusoria, (less than 13mm in shell length) and the perforations bored in the bivalve by bering snails, Neverita didyma and Natica severa. The investigation was carried out in the Kunsan area and in the laboratory from May to October of 1968. 2. The natural mortality of the field population during this period was $12.1\%$ and among this number $38.1\%$ were drilled by boring snails. 3. The common species of the Naticid gastropods, boring snails-Neverite didyma and Natice severa - are encountered in the habitat of M. lusoria. The perforations drilled by these species were broadly bevelled. 4. The location of the holes on the valves varied widely, while most of holes on the valves were located at a relatively definite umbo position. 5. The inner and outer diameters of the holes varied in proportion to the shell length of the clam; each ranging in shell length from 1 to 3mm, 3 to 6mm, and 6 to 13mm, and the outer diameters were 0.4-0.5mm, 0.7-0.9mm and 0.9-1.2mm. On the other hand, the ratio of the inner and outer diameters differed in proportion to the shell length of the clam. 6. Predation rates of Neverita didyma was much greater at night than during the day at room temperature. An average of 1.7 young clams was drilled and consumed, per snail, per day. This rate was greater than that of the Natica severa. 7 Predation rates varied in proportion to the shell length of the clam and the shell height of the snails.

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Plant Distributions and Physicochemical Characteristics of Topsoil on the Reclaimed Dredging Area (임해준설매립지 식물분포와 표층토양의 이화학적 특성)

  • Nam, Woong;Kwak, Young-Se;Jeong, In-Ho;Lee, Deok-Beom;Lee, Sang-Suk
    • Journal of the Korean Institute of Landscape Architecture
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    • v.36 no.3
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    • pp.52-62
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    • 2008
  • By analyzing specific plant distributions and physicochemical characteristics of topsoil in a reclaimed dredging area, baseline data was found of natural landscape planting sites, and developing dredged fill ground. The reclaimed dredging area is five different stands (1, 2, 3, 4 and 5) which were examined in this research. They are located from sea level to 15 meters in altitude and exhibited typical characteristics of the salt marsh in Gwangyang Bay. Species with high constancy in the vegetation on the reclaimed soil were classified into four stages. A total of 12, 15, 22, 27 and 35 different plant species were found and also increased in stands 1, 2, 3, 4 and 5, respectively. Moving from stand 1 to 5, halophytes decreased and non-halophytes increased. Desalination at each stage of the reclaimed dredging area was a driving force affecting the performance and distribution of halophytes and non-halophytes. Overall, 35 quadrats of soil were selected and analyzed for specific physicochemical characteristics of topsoil between O${\sim}$20cm. Results of the physicochemical analysis such as altitude, slope, vegetation and kind of reclaimed dredging soil, exhibited irregular increases or decreases. As survey areas moved from stand 1 to 4, desalination areas, soil acidity, electric conductions, content of salinity, available phosphorus, potassium, chlorine, calcium, and magnesium indicated decreasing patterns; however, total nitrogen, silt, and clay content increased. Cluster analysis and PCA by environmental data within the stands clearly showed five distinct vegetation patterns on the tested reclaimed area. These results indicate that the differences of performance and distribution of vegetation are due to the SAR in the reclaimed soil and related to the natural survival strategy at the given hostile habitat.

Ecological and Morphological Characteristics of Zostera caulescens Miki (Zosteraceae) in Korea (한국산 수거머리말(Zostera caulescens Miki.)의 형태 및 생태적 특성에 대한 연구)

  • Lee, Sang-Yong;Suh, Young-Bae;Kim, Sang-Tae;Choi, Chung-Il
    • Ocean and Polar Research
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    • v.24 no.4
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    • pp.345-357
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    • 2002
  • Ecological characteristics on habitats and morphological features of the seagrass Zostera caulescens Miki in Korea were examined. The biogeographical distribution of Z. caulescens was confirmed in the south coast of the Korea. Zostera caulescens usually inhabits at the inner bay, where is sheltered from wave action and 3.0 to 6.5 m deep. The sediment in habitats is composed of very fine muddy sand or sandy mud. In morphology, Z. caulescens is easily distinguished from other species of the genus by the formation of vegetative canopy on the top of reproductive stems. The number of longitudinal ribs in testa was 24 revealed by scanning electron microscope (SEM) while the number of ribs in Z. marina has been often reported to be 16-20. Purplish anthocyanin spots were displayed on the surface when the testa was removed. We found that the size and shape of leaf epidermal cells in Z. caulescens were very different from those of Z. marina when the leaf cuticles were removed by maceration which could be useful characters for identifying Zostera species. The leaf of Z. caulescens displays two different casts of color when the fresh plant is closely observed. The margins of leaves appear brighter than the center of leaves due to the thickening by the development of paralleled venation in the middle of leaves. The comparison of two populations of Z. caulescens in Korea showed that they were considerably different in their shoot density and biomass. The shoot density and biomass at Gabae population was $367.3 m^{-2}\;and\;725.7g$ dry wt $m^P{-2}$ respectively, while those at Jukrim population were $112.5m^{-2}\;and\;392.0g\;dry\;wt\;m^{-2}$, respectively.