• Title/Summary/Keyword: 군집지수

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Analysis of flood stage difference due to the vegetation in Seomjin river in August 2020 (2020년 8월 홍수시 식생으로 인한 섬진강 홍수위 변화 분석)

  • Kim, Won;Baek, Donghae
    • Proceedings of the Korea Water Resources Association Conference
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    • 2021.06a
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    • pp.2-2
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    • 2021
  • 최근들어 하천내 식생이 차지하는 비율이 크게 증가하고 있으며, 이러한 현상은 하천의 규모나 위치, 댐 유무에 관계없이 전국적으로 발생하고 있다. 식생 면적 비율의 증가는 하천의 육역화로 이어질 뿐만아니라 홍수위를 상승시켜 홍수 안전에 영향을 미칠 수 있다. 본 연구에서는 2020년 8월 섬진강에서 발생한 홍수를 대상으로 식생이 홍수위에 미치는 영향을 분석하였다. 섬진강에는 초본류 뿐만아니라 버드나무류의 목본류가 상당히 분포하고 있으며 이와 같은 식생이 홍수흐름에 큰 영향을 미친 것으로 보인다. 분석을 위해 홍수 이후 섬진강 현지 답사를 통해 식생분포 현황 및 홍수로 인한 영향을 조사하였다. 섬진강의 식생분포 조사를 위해서는 2020년 4월 조사된 유럽 우주국 Sentinel-2 위성영상을 사용하였으며, 정규식생지수(NDVI)와 정규수분지수(NDWI)를 이용하여 하천내 식생밀도를 단계별로 구분하였다. 군집된 식생지수에 따라 USGS의 매닝계수 산정표를 기본으로 식생분포 군집별 조도계수를 산정하여 대상 구간내에 2차원으로 분포시켰다. 수치모형은 NAYS2D 모형을 사용하였으며 대상구간은 섬진강 고달교에서 구례교까지 21.5km이다. 계산조건은 2020년 8월 홍수중 구례교 수위관측소를 기준으로 최대수위가 발생한 시점의 자료를 활용하였다. 고달교에서는 홍수통제소에서 제공하는 홍수량을 상류경계 조건으로 입력하였고 구례교에서는 해당 시각의 수위를 하류경계조건으로 입력하였다. 모형의 검증을 위해 대상구간의 중간에 있는 압록수위관측소 수위를 활용하였다. 식생 유무에 따른 홍수위변화는 조도계수 값에 의해 반영되도록 하였는데 식생이 있는 경우는 현재 상태, 식생이 없는 경우는 모든 지점에 모래와 자갈이 분포하는 것으로 가정하여 계산된 홍수위를 비교하였다. 분석 결과 대상구간에는 전체 면적중 약 56%를 식생이 차지하고 있으며 이로 인해 0.5~1.0m의 홍수위 상승이 발생하는 것으로 분석되었다. 수목으로 인해 2020년 8월과 같은 큰 홍수시에도 홍수위가 크게 상승하는 것으로 분석되었는데 이와 같은 점을 고려하면 하천내 식생이 홍수위에 미치는 영향을 감안하여 적극적인 식생관리 방안이 시행될 필요가 있을 것으로 판단된다.

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Community Structure and Health Assessment of Macrobenthic Assemblages at Spring and Summer in Geoje-Hansan Bay, Southern Coast of Korea (거제한산만에 서식하는 대형저서동물의 춘계와 하계의 군집구조 및 건강도 평가)

  • Jung, Rae Hong;Seo, In-Soo;Choi, Byoung-Mi;Choi, Minkyu;Yoon, Sang-Pil;Park, Sang Rul;Na, Jong Hun;Yun, Jae Seong
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.22 no.1
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    • pp.27-41
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    • 2016
  • This study was performed to investigate the community structure and health assessment of macrobenthic assemblages in Geoje-Hansan Bay, Southern Coast of Korea. Macrobenthos were collected by van Veen grab sampler at May (spring) and August (summer) 2013. The total species number and mean density were 300 species $7.6m^{-2}$ and $1,994ind.\;m^{-2}$, respectively. The major dominant species were the polychaetes Lumbrineris longifolia ($299{\pm}164ind.\;m^{-2}$), Aphelochaeta monilaris ($100{\pm}57ind.\;m^{-2}$), the bivalve Musculista senhousia ($91{\pm}96ind.\;m^{-2}$) and the polychaete Praxillella affinis ($80{\pm}66ind.\;m^{-2}$). From the community statistics [cluster analysis and nonmetric multidimentional scaling (NMDS) ordination], the macrobenthic community was distinguished into two groups of inner bay (farming ground of near Sandal Island) and channel station(from Hansan Island to Chubong Island) group. In this study, the ecological status was assessed by four biotic indices Shannon's H', the ATZI Marine Biotic Index (AMBI), multivariate-AMBI (M-AMBI) and the Environment Conservation Index (ECI). The ecological status of the macrobenthic community in Geoje-Hansan Bay were poorer in the inner bay station than in the channel station. The results of the present study showed that three biotic indices (Shannon's H', M-AMBI and ECI) were valid as an index for evaluating the ecological status than the AMBI.

Vegetation Structure of Sinseonnbong in the Byeonsanbando National Park, Korea (변산반도국립공원 신선봉 지역의 식생구조)

  • Um, Tae-Won;Kim, Gab-Tae;Choo, Gab-Cheul
    • Korean Journal of Environment and Ecology
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    • v.23 no.2
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    • pp.143-150
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    • 2009
  • To investigate the vegetation structure of the mountain ridges ranging of Shins un-Bong, this research set up 14 plots($400m^2$) as survey target areas. As a result of the analysis of woody plant cluster, it was classified as two groups-Quercus variabilis-Quercus serrata community and Carpinus tschonoskii community. Quercus variabilis and Quercus serrata was found as a mostly dominant woody plant species in the ridge areas of Shinsun-Bong, while Carpinus tschonoskii were mixed up partly in high altitudes. High negative correlations were shown between Quercus variabilis-Sambucus sieboldiana and relatively high positive correlation were found to exist between Styrax japonicus-Quercus serrata, Sambucus sieboldiana-Rhododendron schlippenbachii, Tilia amurensis, Styrax obassia-Cornus kousa, Rhododendron schlippenbachii-Carpinus laxiflora, Cornus kousa-Tilia amurensis. Species diversity index(H') of investigated groups were ranged from $1.237{\sim}1.497$, and it was relatively high value compared to that of the vegetation structure of other national park.

Differences in Breeding Bird Communities between Coniferous Forests of Mt. Namsan and Gwangneung Areas (남산과 광릉의 침엽수림에서 번식기 조류 군집의 차이)

  • Rhim, Shin-Jae
    • Korean Journal of Environment and Ecology
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    • v.22 no.3
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    • pp.332-337
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    • 2008
  • This study was conducted to clarify the differences in bird communities in breeding season between coniferous forests of Mt. Namsan and Gwangneung areas from April to August 2006. We chose a study site of 10ha in size for territory mapping of breeding bird community in each area. There were significant difference in DBH distribution of trees and average foliage profiles between both study areas. Number of breeding species and pairs, breeding density, and bird species diversity were higher in Gwangneung area than in Mt. Namsan area. Number of bird species and breeding pairs belonged to hole and canopy guild were different between both study areas. The difference in breeding bird communities between both study areas may be related with forest structure. For the protection and management of birds, greater structural complexity would be needed in Mt. Namsan area.

Investigating spatial clusters of single-person households and low-income elderly single-person using penalized likelihood (벌칙가능도함수를 이용한 1인가구와 저소득 독거노인의 공간군집 탐색)

  • Song, Eunjung;Lee, Woojoo
    • Journal of the Korean Data and Information Science Society
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    • v.28 no.6
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    • pp.1257-1260
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    • 2017
  • Single-person households recently have been rapidly increasing and one reason may be the increment in elderly single-person. Since the change of living patterns is relevant to the government policy direction, it is important to understand how single-person households are clustered and which factors have influence on them. In this study, we tried to detect spatial clusters of single-person households and low-income elderly single-person households after adjusting for deprivation index. A recently developed fused lasso for Poisson data was used for data analysis and we provided the details on how to use it in R. From these analysis results, we observed the effect of socioeconomic level on the clusters and explained the reason why spatial clusters are shown after adjusting for deprivation index.

Forest Structure of Subalpine Region from Hyangjeukbong to 2nd Deogyusan in Deogyusan National Park, Korea (덕유산국립공원 아고산(향적봉-제2덕유산) 지역의 산림군집구조)

  • 김갑태;추갑철
    • Korean Journal of Environment and Ecology
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    • v.18 no.2
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    • pp.142-149
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    • 2004
  • To investigate the vegetation structure of subalpine region from Hyangjeukbong to 2nd Deogyusan, 20 plots(100$m^2$) set up with random sampling method were surveyed. Three groups Quercus mongolica community, Betula ermanii - Picea jezoensis - Taxus cuspidata community, Taxus cuspidata - Qurecus mongolica - Betula ermanii community were classified by cluster analysis. Quercus mongolica, Taxus cuspidata and Betula ermanii were found as a major woody plant species in the subalpine region from Hyangjeukbong to 2nd Deogyusan. In this area, Korean endemic species, Abies koreana was distributed small amounts. In future, importance percentage of Abies koreana might be decreased, but that of Betula ermanii might be increased. High positive correlations was proved between Betula ermanii and Rhododendron schlippenbachii, Rhododendron mucronulatum var. ciliatum ; Acer tschonoskii var. rubripes and Acer mono; Syringa velutina and Magnolia sieboldii and relatively high negative corrlations was proved between Betular ermani and Acer tschonoskii var. rubripes ; Quercus mongolica and Acer mono; Abies koreana and Tripterygium regelii, Weigela subsessilis. Species diversity(H') of investigated groups were ranged 1.0316∼1.1776 and it was similar to those of the ridge area of the national parks in Baekdudaegan.

Ectomycorrhizal Fungal Diversity on Abies korea and Taxus cuspidata at Two Altitudes in Mt. Halla (고도에 따른 한라산 구상나무와 주목의 외생균근균 다양성 비교)

  • Lee, Ji-Eun;Eom, Ahn-Heum
    • The Korean Journal of Mycology
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    • v.47 no.3
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    • pp.199-208
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    • 2019
  • In this study, the community structures of the ectomycorrhizal (ECM) fungi in the roots of Abies koreana and Taxus cuspidata were investigated at different altitudes of Mt. Halla. We identified the collected ECM root tips based on morphological characteristics and phylogenetic analysis through sequencing of the rDNA ITS regions. From the roots of A. koreana and T. cuspidata, 11 species and 12 species were identified, respectively. The Shannon's index and species evenness and abundance of the ECM fungi were higher in the higher than lower regions, regardless of host plant species, however, the number of ECM root tips showed the opposite pattern. The community similarity among the ECM fungi in A. koreana was significantly higher than that among the ECM fungi in T. cuspidata or than that between A. koreana and T. cuspidata (p < 0.05). These results could be useful for the conservation and management of the habitat of A. koreana, which is threatened with extinction due to increasing ambient air temperature.

Natural Environmental Characteristics and Vegetation Structure of Wikstroemia trichotoma and W. ganpi, Thymelaeaceae (산닥나무(Wikstroemia trichotoma), 거문도닥나무(W. ganpi) 자생지 생육환경 및 입지환경 특성)

  • Yonghwan Son;Hyun-Jun Kim;Sun-Young Lee
    • Proceedings of the Plant Resources Society of Korea Conference
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    • 2022.09a
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    • pp.60-60
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    • 2022
  • 우리나라에 분포하는 팥꽃나무과(Thymelaeaceae) 산닥나무속(Wikstroemia) 식물은 산닥나무[Wikstroemia trichotoma (Thunb.) Makino], 거문도닥나무[W. ganpi (Siebold & Zucc.) Maxim.] 2종이 분포하고 있다. 산닥나무는 낮은 산지의 그늘진 계곡에서 주로 자생하며, 거문도닥나무는 임연부에서 주로 자생하는 것으로 알려져 있다. 현재 우리나라에 남아있는 자생지는 기후변화, 남획 등을 이유로 과거에 비하여 축소되어 유전자원의 현지 내·외 보전이 적극적으로 권장된다. 따라서 본 연구에서는 삼지닥나무, 산닥나무, 거문도닥나무의 생육환경 특성을 파악하여 보존 및 증식을 위한 기초자료로 활용하는 데 그 목적이 있다. 연구 결과, 확인된 자생지는 3지역 7개소로 산닥나무는 순천지역, 영암지역, 거문도닥나무는 고흥지역에 자생하는 것으로 확인되었다. 산닥나무는 해발고도 72-248 m, 사면 방위는 북사면, 동사면, 경사는 30-55°의 급경사지에서 주로 자생하는 것으로 확인되었으며, 방형구(10×10 m) 내 개체수는 8-20 개체가 확인되었다. 거문도닥나무는 해발고도 65-76 m, 사면방위는 동사면, 경사는 20-60°, 개체수는 15-25 개체가 확인되었다. 군집분석은 지표종 분석을 통해 가장 유의한 2개 군집으로 나뉘었으며, 산닥나무는 소나무 군집(Pinus densiflora Sieblod & Zucc.), 거문도닥나무는 곰솔(Pinus thunbergii Parl.) 군집으로 확인되었다. 군집의 안전성, 다양성을 나타내는 척도인 종다양성, 최대종다양도, 균재도 및 우점도지수는 소나무 군집 1.2303, 1.2788, 0.9621, 0.0389, 곰솔 군집이 1.1821, 1.2359, 0.9552, 0.0448로 확인되었다.

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Characteristics of Bird Community in Sihwa South Grassland, Korea (시화호 남측 초지지역의 조류 군집 특성)

  • Park, Chi-Young;Kim, Ho-Joon;Paik, In-Hwan;Yu, Jae-Pyoung;Paik, Woon-Kee;Lee, Joon-Woo
    • Korean Journal of Environment and Ecology
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    • v.29 no.4
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    • pp.516-524
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    • 2015
  • This study was characteristics of bird community conducted to from 2009 to 2010 in Sihwa South Grassland, Gyeonggi-do, Korea. Total 49 species were recorded and the sum of maximum counts was 2,258 individuals. Species diversity was 2.21 and the species richness was 6.22. In South Reclaimed, we recorded maximum score of 38 species. and maximum score of 1,083 individuals in Dinosaur Egg Fossil. Comparison between areas were use average species diversity and species richness. Mostly Dinosaur Egg Fossil and South Reclaimed were higher than Sihwa Lake upstream. As a results of the ANOVA test, all areas were different. also, Sihwa Lake upstream only difference was that the bird community. In the season there was a significant difference between the Number of species and species richness. Number of species and species richness were significant differences depending on the season. but individuals and species diversity were no significant differences. In the year there was a no significant difference between the Number of species and individuals. but species diversity and species richness were significant differences. As a result, Between areas was different patterns of bird communities. but including water space Dinosaur Egg Fossil and South Reclaimed were showed a similar bird communities and bird diversity was higher. In the season, the resident was using of consistent patterns. but, There were differences depending on the migratory patterns of populations. In the year, every year was communities of a similar patterns. Sihwa South Grassland is of the high conservation value ecosystem as the only domestic. Propose an opinion for maintaining biodiversity when planning future habitat composition and environmental decrease.