• 제목/요약/키워드: dominant-species change

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The Community Structure And Distribution Of Phytoplankton Of The Kum River Estuary

  • Shim, Jae-Hyung;Yang, Jae-Sam
    • 한국해양학회지
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    • 제17권1호
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    • pp.1-11
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    • 1982
  • A study on the community and distribution of phytoplankton of the Kum River Estuary has been done in fall, 1980 and spring, 1981. Ond hundred and one taxa representing 22 families, 41 genera, 107 species, 2 varieties, and 2 forms were identified. The community of the study area composed mainly of diatom species icluding the very small fraction of dinoflagellates, blue-greens and greens. The dominant species were Skeletonema costatum, Paralia sulcata, and Asterionella kariana. The total standing crop of phytoplankton of winter samples was 115,000 cells/1 in average and that of spring samples was, 1,320,333 cells/1 in average. Of the representative members, dominant species above appeared moree than 10% of the total standing crop, Skeletonema costatum being maximized up to 46%. In spring Asterionella japonica, Thalassionema nitzschioides, and Chaetoceros curvistetus appeared 3∼8%, and Thalassiosira excentricus 3% in winter. The distribuion of marine forms showed negative correlation with that of fresh water forms, although the brackish-water forms showed no relationship. This change pattern of marine, brackish and fresh-water forms are discussed with the results of time series analysis. A list of phytoplankton species observed in this study is added.

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이원면 굴, Crassostrea gigas 양식어장의 월별 식물플랑크톤 종조성 및 수질환경 변화 (Monthly Variation of Phytoplankton Composition and Water quality in Cupped Oyster Crassostrea gigas Culture Area in Iwon, Korea)

  • 김수경;김병호;오은경;송기철;박승윤;한기연;임현정
    • 한국패류학회지
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    • 제30권3호
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    • pp.249-258
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    • 2014
  • Phytoplankton species composition and ecological index (diversity, evenness, richness and dominance) were analysed from April 2013 to March 2014 at 10 stations of cupped oyster, Crassostrea gigas culture area in Iwon coast, Korea. Seasonal and positional variation of phytoplankton standing crops, biomass, dominant species and water quality were distinctively different according to occasionally inflow of Iwon dam reservoired water. The composition of phytoplankton species were Bacillariophyceae 98, Dinophycease 22, Chlorophycease 13, Cyanophyceae 8, Silicofalgellate 4, Euglenophyceae 2, Cryptophyceae 1 species. The most dominant species was Bacillariophyceae as 64.0%. The highest biomass of phytoplankton recorded in September as $40,910{\times}10^3$ cell/L at the station 1, near from inland water inflow area. Ecological indices (diversity, richness, evenness, and dominance index), used for structural change of phytoplankton community and water quality (temperature, dissolved oxygen, salinity) showed difference of spatiotemporal property also.

완도 연안 낭장망에 채집된 어류 군집구조의 12년 전후 변화 (Change of Structure Community of Fish Collected by a Gape Net with Wings after 12 Years in the Coast of Wando Island, Korea)

  • 유준택;김진구;최문성
    • 한국수산과학회지
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    • 제47권5호
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    • pp.659-666
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    • 2014
  • Our aim was to compare the community structure of fish in the coast of Wando Island between 2001 and 2013. Using a gape net with wings, we collected 61 taxa, wherein the most dominant species was Engraulis japonicus. The sea temperature in the middle layer of the survey station in 2001 (after June) was obviously higher than that in 2013, which was < $20^{\circ}C$. Except for Thryssa kammalensis in 2013, the log transformed individuals of seven dominant species, selected using a SIMPER (similarity-percentages procedure) analysis, decreased. Decreases in the individuals of Gobiidae spp., the warm-water species Trichiurus japonicus and Conger myriaster, and the migratory species Syngnathus schlegeli, Setipinna taty and Sardinella zunasi, which arrive in the southern coastal waters of Korea during summer-autumn, could be due to decreasing sea temperature in 2013. Thus, fish species diversity, estimated from rarefaction and k-dominance curves, declined in the coastal waters of Wando Island from 2001 to 2013, resulting in a significant difference in fish community structure.

여의도공원 내 조성된 '자연생태의 숲'의 초기 식생 변화 (Early Changes in Vegetation after the Construction of 'the Ecological Forest' in Youido Park)

  • 이상원;김동엽
    • 한국환경복원기술학회지
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    • 제4권1호
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    • pp.41-51
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    • 2001
  • 'The Ecological Forest' in Youido Park was intended to be an artificial forest in urban center, following the form of natural forests in central Korea. This study was to investigate the planting plan and the vegetation change of 'the Ecological Forest' and to compare it with natural forests of similar plant composition. The natural forests had slopes between $12^{\circ}$ and $21^{\circ}$, whereas 'the Ecological Forest' had slopes between $2^{\circ}$ and $6^{\circ}$. It was unlikely that the slope condition was adequate to show 'toposequence succession' at 'the Ecological Forest'. The soil bulk density and soil hardness of 'the Ecological Forest' were higher than those of the natural forests. The soil pH of 'the Ecological Forest' was 7.45, which was greater than that of the natural forests. There were some changes in plant composition and amounts 2 years after the construction : the number of conifers was reduced from 383 to 338 ; the number of deciduous trees was reduced from 4717 to 1158. It was because of the young trees dead in the sub-tree layer. The herbaceous species planted were 14 families, 31 species, which increased to 37 families, 93 species after 2 years. In case of horizontal structure of vegetation, trees and shrubs were distributed evenly in the natural forests, whereas 'the Ecological Forest' showed uneven distribution with higher total density. In case of vertical structure of vegetation, the natural forests had distinctive layers with dominant species distributed in each layers. In 'the Ecological Forest', however, dominant species were only in tree layer. The natural forests had greater average tree height, tree density, however, and basal area than 'the Ecological Forest'. The results showed that there were some differences in the structure between 'the Ecological Forest' and natural forests. The management plan should be applied in order that the natural condition be restored in 'the Ecological Forest' by competition between plant species and natural processes.

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동해 연안 수괴 특성에 따른 식물플랑크톤 우점종의 계절 변동 (Seasonal Change of Phytoplankton Dominant Species Based on Water Mass in the Coastal Areas of the East Sea)

  • 심정민;권기영;김상우;윤병선
    • 해양환경안전학회지
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    • 제21권5호
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    • pp.474-483
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    • 2015
  • 동해 연안 식물플랑크톤의 계절별 분포 특성과 해양환경 요인과의 상호관계를 파악하기 위하여 2009년 2월, 5월, 8월 및 11월에 연안 18개 정점에 대해 조사하였다. 조사기간 중 출현한 식물플랑크톤은 규조강 37종, 와편모조강 22종, 유글레나조강 1종, 규질편모조강 3종 및 은편모조강 1종으로 나뉘었다. 현존량은 $1.2{\times}10^3-246.6{\times}10^3cells/L$(평균 $24.8{\times}10^3cells/L$)의 분포 범위를 보였으며 5월에 가장 높았다. 주요 우점종은 Leptocylindrus danicus, Chaetoceros affinis, Pseudo-nitzschia pungens 및 Thalassionema nitzschioides 등이 출현하였다. 해양환경 요인과의 상관분석 결과 식물플랑크톤 현존량은 pH, 용존산소, 클로로필-a 및 부유물질과 양의 상관관계를 보였으며, 규산규소와는 음의 상관관계를 보였다. 식물플랑크톤 우점종의 계절 변동은 등밀도선 상의 수온(T)-염분(S)도로 구분한 수괴 특성에 영향을 받는 것으로 나타났으며, 특히 5월은 수온, 8월은 염분 분포와 관계가 있었다. 현존량과 종조성을 바탕으로 다원척도 분석을 한 식물플랑크톤의 공간적인 분포는 경북 죽변과 울진을 기점으로 강원연안 그룹(Group A)과 경북연안 그룹(Group B)으로 나뉘어졌다.

Population Changes of Moths (Insecta: Lepidoptera) from Mt. Wolchul National Park, Jeollanam-do, Korea

  • Choi, Sei-Woong;Park, Marana;Chang, Young-Hyo
    • Journal of Ecology and Environment
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    • 제30권3호
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    • pp.245-250
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    • 2007
  • We investigated the moth fauna and monthly changes in moth populations at three sites - Dogapsa, Gyungpodae and Muwisa - in Mt. Wolchul National Park, Jeollanam-do, South Korea. From February to October, 2006, we collected a total of 1677 individuals comprising 348 species in 14 families. Monthly changes in the abundance of species and individuals showed an M-shaped pattern, with the highest peak in June and a second high peak in August. The diversity of the three dominant families (Noctuidae, Geometridae and Pyralidae) at the three sites varied, possibly due to differences in vegetation and other environmental factors. Diversity at Dogapsa was relatively higher than Gyungpodae and Muwisa, but, the fauna at Dogapsa more closely resembled Muwisa than Gyungpodae. 28 species occurred at the same time in all three sites, included the families Geometridae (14 species), Noctuidae (9 species), Pyralidae (2 species), Arctiidae (1 species), Nolidae (1 species), and Limacodidae (1 species). The present study provided baseline information about biodiversity and phenological patterns of moth abundance and permitted evaluation of moth biodiversity as a monitoring tool for vegetation structure and environmental change.

지리산 나비의 고도에 따른 다양성과 서식 분포 (Altitudinal diversity and distribution of butterflies inhabiting Mt. Jirisan, South Korea)

  • 이상훈;안나현;안정섭
    • 환경생물
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    • 제38권4호
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    • pp.497-506
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    • 2020
  • 이 연구에서 지리산의 낮은 고도에서부터 높은 고도까지 나비의 종다양성, 고도에 따른 생태적 특성, 우점종의 고도 분포에 대해 알아보았다. 나비는 총 5과 58종 769개체의 나비를 확인하였다. 낮은 고도와 높은 고도에서 종다양성은 높게 나타나고 있었다. 군집분석을 통해 3개(낮은 고도, 중간 고도, 높은 고도)로 구분하였으며, 낮은 고도에 비해 높은 고도에서는 서식지 범위가 좁은 종의 비율이 높았으며, 단식성 나비의 비율이 높게 나타나고, 다화성 나비의 비율이 높게 나타났다. 배추흰나비(Pieris rapae)는 600m 이하의 고도에서 서식하고, 큰흰줄표범나비(Argynnis ruslana), 먹그늘나비(Lethe diana)는 900 m 이상의 고도에 서식하며, 특히 큰흰줄표범나비(Argynnis ruslana)는 1,000m 이상에서 서식하고 있었다. 본 연구를 바탕으로 지속적인 모니터링 실시를 통해 지리산에서 기후변화에 따른 나비의 고도 분포 변화 및 다양성 변화 양상을 확인할 수 있을 것으로 생각된다.

계절별(季節別), 재배작물(栽培作物) 및 경작지별(耕作地別) 잡초식생변화(雜草植生變化) (Change in Weed Flora with Season and Cultivated Crop and Land)

  • 양환승;전재철;황인택
    • 한국잡초학회지
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    • 제4권1호
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    • pp.4-10
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    • 1984
  • 전북지역(全北地域)의 밭 잡초식생변화(雜草植生變化)를, 재배작물별(栽培作物別) 및 경지형태별(耕地形態別) 조사(調査)하였다. 1. 전북지역(全北地域) 밭에 발생하는 잡초(雜草)는 18과(科) 44종(種)으로, 일년초(一年草) 22종(種), 월년초(越年草) 11종(種) 및 다년초(多年草) 9종(種)으로 구성(構成)되어 있었다. 발생빈도별(發生頻度別)로 보면, 바랭이가 67.2%로 가장 높았으며, 다음으로 쇠비름, 명아주, 망초의 순위(順位)였다. 3. 조사지역(調査地域)의 약(約) 60%에 해당(該當)되는 지역(地域)의 잡초식생(雜草植生)이 Simpson 지수(指數) 0.20에서 0.50사이를 나타내었다. 4. 밭에서의 Simpson 지수(指數)는 계절적(季節的)으로 변화(變化)되어, 6월(月)8일(日)의 0.65가 11월(月)10일(日)에 0.15로 감소(減少)되어 잡초식생(雜草植生)이 다양화(多樣化)되고 있음을 나타내었다. 5. 경지형태별(耕地形態別)로 보면 답이작전(沓裏作田)에서는 독새풀과 여뀌, 숙전(熟田)에서는 바랭이와 쇠비름이 우점종(優占種)이었고 야산개간지(野山開墾地)에서는 쑥을 비롯한 다양(多樣)한 초종(草種)들이 고루 발생(發生)하고 있었다. 6. 콩을 비롯한 5개 작물포(作物圃)의 Simpson 지수(指數)는 평균(平均) 0.4로써 작물(作物)의 종류(種類)에 관계없이 쇠비름과 바랭이가 우점종(優占種)이었고, 여뀌, 명아주, 쇠비름, 망초 등이 차우점종(次優占種)으로 나타났다.

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Climate change and fluctuations of pelagic fish populations in the Far East region

  • Gong, Yeong;Suh, Young-Sang
    • Journal of Ecology and Environment
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    • 제35권1호
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    • pp.15-25
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    • 2012
  • Time series of ocean climate indices and catch records were used to identify the alternation patterns of pelagic fish populations in relation to climate regime shifts. During 1910-2008, an orderly alternation of dominant pelagic fish groups was observed in the Tsushima Warm Current (TWC; Yellow Sea-East China Sea-East Sea/Japan Sea) and Kuroshio-Oyashio Current (KOC; Northwestern Pacific) regions. After the collapse of herring fishery in the late 1920s, the sardine (A group) dominated in the 1930s, 3 other species (C group; Pacific saury, jack mackerel, and anchovy) dominated in the 1950s-1960s, chub mackerel (B group) dominated in the 1970s, and then sardine (A group) dominated again during cool regime in the 1980s. As sardine biomass decreased in association with the climate regime shift that occurred in the late 1980s, catches of C group immediately increased after the regime shift and remained at high levels during warm regime in the 1990s. Alternations of dominant fish groups occurred 6 times between 1910 and 2008. The dominant period of the 7 species lasted for 10-20 years. The catch of Pacific sardine in the TWC and KOC regions showed a negative correlation with the catch of the other 5 species (Pacific herring, anchovy, jack mackerel, Pacific saury, and common squid), suggesting that the abundance of the 5 species is strongly affected by the abundance of Pacific sardine in relation to the climate regime shifts. The total catch level of the 7 species in the KOC region was generally higher than that in the TWC region before 1991 but was lower after 1992, suggesting that the fish populations in the Pacific side are shifted to the TWC region by zonal oscillation of the oceanic conditions in relation to the climate regime shift in the late 1980s.

제주도 저지대 묵밭 식물군락의 2차 천이 (Early Vegetation Succession in Abandoned Field in Cheju Island)

  • 유영한;이창석
    • The Korean Journal of Ecology
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    • 제26권4호
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    • pp.209-214
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    • 2003
  • 제주도의 저지대 묵밭에서 일어나는 2차 천이의 특성을 밝히기 위하여 식생의 높이, 생육형, 종풍부도와 종다양성지수, 식피율, 우점도지수의 변화를 조사하고, 그 결과를 내륙의 결과와 비교하였다. 또한 시간의 경과에 따른 전체적인 식생의 변화를 알아보기 위하여 다변량통계기법을 사용하였다. 제주도 묵밭의 식생천이의 특징은 내륙에 비하여 종수가 적고, 식생의 높이가 낮고, 초본층이 우점하는 기간이 길고, 종다양성지수의 변화 유형이 다르고, 천이후기종의 출현이 매우 늦었다. 우점종에 의한 식생천이 계열은 주름잎(0.5∼l년)→큰망초(2년)→쑥(4년)→쑥-낭아초(5년)→찔레꽃-참억새(8년)→참억새(12년)→다년생초본→관목(15년)→예덕나무(20년)→까마귀쪽나무 또는 후박나무(20년 이후)로 추정되었다. 유집분석(Cluster analysis), Twinspan에 의한 분류와 주성분분석(PCA)에 의한 배열의 결과 묵밭은 초기묵밭(0.5∼l년차), 중기묵밭(2∼8년차)와 후기묵밭(8∼20년차)의 세 집단으로 시간 경과에 따라 구분되었다.