• Title/Summary/Keyword: Ecological distribution

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Distribution Pattern of Principal Species in the Mantle Community (임연군락의 주요종 분포양식)

  • Jung, Yong-Kyoo;Jong-Won Kim
    • The Korean Journal of Ecology
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    • v.17 no.4
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    • pp.513-521
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    • 1994
  • Distribution patern of 30 species that are occurring predominantly in the mantle communities (Mantelgesellschaften) in South Korea was studied. The study was arried out by geographic and bioclimatic analysis on 368 releves obtained from the Zurich-Montpellier School's method, which involves direct analysis on the latitude, altitude, annual mean temperature and the lowest temperature of the site. Rosa multiflora and Pueraria thunbergiana which are regarded as repersentative pioneer species to the mantle community has the highest frequency, 70.1% and 60.3%, respectively. Three distribution patterns were recognized, i.e. northern type, central type and southern type, and each type was characterized by horizontal and altitudinal amplitude. Their concetrate distribution ranges on the annual mean temperature were 8~11℃, 9~12℃ and 10~13℃, respectively. It was recognized that tendencies of overlapping and continuous distribution pattern of the types and species exist. Geographically, the souther limit f the northern type is 35.5。N and the northern limit of the southern type 37.0。N. The central type is located at an coincided with the previous study in which cool-temperate forests were synchorologically indentified into northern/altimontane, certral/montane and southern/submontane type. The subsidiary knowledges from this study will provide practical information on the constructuin of the fence plant community for environmental conservation.

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Distribution of Phytolacca americana in a coastal sand dune

  • Min, Byeong-Mee
    • Journal of Ecology and Environment
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    • v.37 no.2
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    • pp.81-90
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    • 2014
  • This study examined the main factors affecting the distribution of Phytolacca americana, an exotic plant species in Korea, in coastal sand dunes. The areas examined from June 2004 to February 2006 were in Sindusagu where was located on Sindu-ri, Wonbuk-myen, Taean-gun, Chungcheongnam-do. The vegetation, sediment properties, sizes and ages of Robinia pseudoacacia, P. americana and Pinus thnunbergii and spatial distribution of P. americana were assessed. Firstly, correlation coefficients (CC) between P. americana's root biomass and sediment properties were not significant. Secondly, of the four community types, P. americana was not in the mixed herbaceous community and its density was the highest in the P. thunbergii-R. pseudoacacia and R. pseudoacacia community The Poisson distribution analysis revealed the distribution of P. americana to be severely clumped. The root biomass of P. americana and the basal area of R. pseudoacacia were significantly correlated, but the CCs between P. thunbergii and other two species were not significant. The ages of P. americana and R. pseudoacacia in a quadrat were significantly correlated. Thirdly, P. americana's ages in a quadrat were mostly similar to each other. Therefore, the spatial distribution of P. americana was largely influenced by R. pseudoacacia but not by the sediment properties, and plants in a narrow area were concurrently germinated.

A Study on the Distribution of Streamside Vegetation in Kyonganchon (경안천에서 하천변 식생의 분포에 관한 연구)

  • Cho, Do-Soon
    • The Korean Journal of Ecology
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    • v.18 no.1
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    • pp.55-62
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    • 1995
  • This study was conducted to investigate the distribution pattern of plants on streamside of Kyonganchon, which is a tributary of the Han River, and to determine the relationships between plant distribution and environmental factors. Fifteen study sites were selected along the Kyonganchon, and vegetation distribution pattern and soil environmental factors were determined. The most frequently ocurring species in the study sites were Persicaria thunbergii, Persicaria hydropiper, Echinochloa crus-galli and Bidens frondosa, and among them the two Persicaria species were dominants of the community. Many species showed different distribution along the stream:Chenopodium album, Equisetum arvense and Setaria viridies occurred in the upstream region, while Rumex crispus, Leonurus sibiricus and Rorippa islandica occurred in the middle and downstream regions. Analysis of soil properties showed that organic matter and clay content were higher in the upstream region while sand content was higher in the downstream region. The results of DCA ordination showed that axis one was positively correlated with organic matter and clay content and negatively correlated with sand content, indicating that the distribution pattern of vegetation along the Kyonganchon was determined by elevational gradient from upstream to downstream region or gradient of stream width and water level, and by soil organic matter content and soil texture related to these gradients.

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Modeling the Spatial Distribution of Black-Necked Cranes in Ladakh Using Maximum Entropy

  • Meenakshi Chauhan;Randeep Singh;Puneet Pandey
    • Proceedings of the National Institute of Ecology of the Republic of Korea
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    • v.4 no.2
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    • pp.79-85
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    • 2023
  • The Tibetan Plateau is home to the only alpine crane species, the black-necked crane (Grus nigricollis). Conservation efforts are severely hampered by a lack of knowledge on the spatial distribution and breeding habitats of this species. The ecological niche modeling framework used to predict the spatial distribution of this species, based on the maximum entropy and occurrence record data, allowed us to generate a species-specific spatial distribution map in Ladakh, Trans-Himalaya, India. The model was created by assimilating species occurrence data from 486 geographical sites with 24 topographic and bioclimatic variables. Fourteen variables helped forecast the distribution of black-necked cranes by 96.2%. The area under the curve score for the model training data was high (0.98), indicating the accuracy and predictive performance of the model. Of the total study area, the areas with high and moderate habitat suitability for black-necked cranes were anticipated to be 8,156 km2 and 6,759 km2, respectively. The area with high habitat suitability within the protected areas was 5,335 km2. The spatial distribution predicted using our model showed that the majority of speculated conservation areas bordered the existing protected areas of the Changthang Wildlife Sanctuary. Hence, we believe, that by increasing the current study area, we can account for these gaps in conservation areas, more effectively.

Prediction of Changes in Habitat Distribution of the Alfalfa Weevil (Hypera postica) Using RCP Climate Change Scenarios (RCP 기후변화 시나리오 따른 알팔파바구미(Hypera postica)의 서식지 분포 변화 예측)

  • Kim, Mi-Jeong;Lee, Heejo;Ban, Yeong-Gyu;Lee, Soo-Dong;Kim, Dong Eon
    • Korean journal of applied entomology
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    • v.57 no.3
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    • pp.127-135
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    • 2018
  • Climate change can affect variables related to the life cycle of insects, including growth, development, survival, reproduction and distribution. As it encourages alien insects to rapidly spread and settle, climate change is regarded as one of the direct causes of decreased biodiversity because it disturbed ecosystems and reduces the population of native species. Hypera postica caused a great deal of damage in the southern provinces of Korea after it was first identified on Jeju lsland in the 1990s. In recent years, the number of individuals moving to estivation sites has concerned scientists due to the crop damage and national proliferation. In this study, we examine how climate change could affect inhabitation of H. postica. The MaxEnt model was applied to estimate potential distributions of H. postica using future climate change scenarios, namely, representative concentration pathway (RCP) 4.5 and RCP 8.5. As variables of the model, this study used six bio-climates (bio3, bio6, bio10, bio12, bio14, and bio16) in consideration of the ecological characteristics of 66 areas where inhabitation of H. postica was confirmed from 2015 to 2017, and in consideration of the interrelation between prediction variables. The fitness of the model was measured at a considered potentially useful level of 0.765 on average, and the warmest quarter has a high contribution rate of 60-70%. Prediction models (RCP 4.5 and RCP 8.5) results for the year 2050 and 2070 indicated that H. postica habitats are projected to expand across the Korean peninsula due to increasing temperatures.

The distribution and three newly reported species of aerial algae at Mt. Gwanggyo, Korea

  • Kim, Ji-Won;Lee, Ok-Min
    • Journal of Ecology and Environment
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    • v.37 no.4
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    • pp.327-339
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    • 2014
  • This research includes the identification and cultivation of aerial algae from 33 sites located in Mt. Gwanggyo of Gyeonggi-do, Korea, from March 2011 to August 2012. The ecological factors of aerial algae were analyzed and a total of 29 taxa were identified in 4 phyla, 5 classes, 11 orders, 15 families, 19 genera, 28 species and 1 variety; 12 taxa of cyanophytes, 8 taxa of chrysophytes, and 9 taxa of chlorophytes were found. As for newly recorded cyanophytes of Korea, Komvophoron jovis, Microcoleus steenstrupii, and Nostoc edaphicum appeared. Komvophoron jovis, previously known to grow on rocks and boulders, appeared in soil. Microcoleus steenstrupii, reported to appear in desert soils, appeared on the wet surface of the soil after rain. Nostoc edaphicum, in symbiosis with fungi, appeared on tree bark as the lichen. Thus, there are a total of 99 reported taxa of Korean aerial algae, including 3 species that were discovered in this study.

Species Associations with Spatial Autocorrelation Analysis of Pinus rigida and Pyrola japonica

  • Huh, Man-Kyu;Huh, Hong-Wook;Kim, Chang-Ho
    • The Korean Journal of Ecology
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    • v.22 no.6
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    • pp.349-354
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    • 1999
  • The spatial distributions of allelic frequencies and ecological traits by randomization were studied in the natural population of two species (Pinus rigida and Pyrola japonica). Both species showed significant positive spatial autocorrelation as measured by Moran's I. In P. rigida, the genetic similarity was shown in individuals within up to a scale of 18 m distance and this is partly due to combination of pollen and seed dispersal by wind or men. In P. japonica, significant spatial autocorrelation was consisted of a scale of 8 m intervals. These population structure in the distribution of allelic frequencies is related to mating systems such as outcrossing and vegetative spread. The results also indicate that positive species associations between P. rigida and P. japonica can occur when both species select the same habitat or require the same environmental conditions.

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Asymmetry in Reproductive Character Displacement

  • Jang, Yi-Kweon
    • Journal of Ecology and Environment
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    • v.31 no.4
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    • pp.255-260
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    • 2008
  • A commonly held view in studies of character displacement is that character states of both species are shifted in areas of sympatry. This view has been confirmed in an overwhelming number of cases for ecological character displacement. Excluding species pairs in which one of the two interacting species is found only within the distribution of the other species and species displaying gynogenesis, the pattern of reproductive character displacement is asymmetrical in that the shift in character states between areas of symaptry and allopatry occurs in only one of the two interacting species. Hypotheses for the reasons behind this asymmetry in reproductive character displacement include (1) homogenization by gene flow, (2) other mechanisms of reproductive isolation, and (3) sufficient reproductive isolation being provided by one of the interacting species exhibiting a pattern of reproductive character displacement. Because reproductive isolation can be achieved by divergence at any point in a sequence of premating reproductive behaviors and postmating developments, it is necessary to understand the mechanisms of reproductive isolation of two interacting taxa in areas of sympatry and allopatry and to analyze the relative contributions of potential factors to reproductive isolation to disentangle hypotheses for the patterns of asymmetry.

An Ecological Study on the Flora of Odongdo Island (오동도 식물상에 관한 생태학적 연구)

  • Kim, Jong-Hong;Chang, Seok-Mo
    • The Korean Journal of Ecology
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    • v.6 no.3
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    • pp.208-226
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    • 1983
  • The vegetation of Odongdo island was surveyed over twenty-nine times from April, 1982 to August, 1983. This island is located at 127。46'05'∼127。39'37'E. longitude and 34。40'20'∼34。48'14'N. latitude. The vegetation of this island consisted of 94 families, 261 genera, 314 species, 53 varieties and 6 formae. And among them were 170 species of woody plants and 203 species of herbs. The community of evergreen broad-leaved trees comprised a total of 44 species including Sasa coreana Nakai and camellia japonica L. and the distribution of evergreen broad-leaved trees was good in this island as a whole. Sasa coreana Nakai, Castanopsis cuspidata var. sieboldii Nakai, Ficus erecta Thunb., Ficus nipponica Fr. et Sav, Stauntonia hexaphylla (Thunb.) Decne, Cinnamomum japonicum Sieb., Machilus thunbergii S. et Z., Lozoste lancifolia (S. et Z.) Bl., Ilex intergra Thunb., Camellia japonica Thunb., Hedera rhombea Bean and Ardisia japonica Bl. etc. in this island were autochthonous flora and their preservation is required.

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Ecological Studies on the Seed Production and Natural Regeneration in Hornbeam Forest (개서나무林의 種子生産과 天然更新에 관한 生態學的 硏究 1. 기초연구)

  • Rim, Young-Deuk;Ho-Kam Kang;Nobukazu Nakagoshi
    • The Korean Journal of Ecology
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    • v.14 no.1
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    • pp.1-7
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    • 1991
  • This study was carried out to estimate the seed crop of Carpinus forest in Piagol of Mt. Chiri for six years and the results obtained were as follows; Upper two layers of Capinus forest were dominated by C. tschonoskii and Subfall tree layer ranging from 15.40 to 17.20 m in height. The distribution of seed weight of C. tsconoski was skewed to light weight classes. Most seeds fall in November. The best crop was shown in 1984, while virtually no crops in 1985. Since 1985, annual seed crop increased gradually.

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