• Title/Summary/Keyword: 우점도 지수

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Effect of Repeated Use of Same Herbicide on Weed Growth in Lowland Rice (제초제(除草劑)의 연용(連用)이 논잡초(雜草) 발생(發生)에 미치는 영향(影響))

  • Choi, C.D.;Kim, S.C.;Hwang, D.Y.
    • Korean Journal of Weed Science
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    • v.9 no.1
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    • pp.39-45
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    • 1989
  • An experiment was conducted at the Yeongnam Crop Experiment Station for 4 years from 1985 to understand the effect of repeated use of same herbicide on weed growth. For this, the most common 6 herbicides, butachlor, bifenox, butachlor/pyrazolate, piperophos/dimethametryne, bentazon and propanil were used as single treatment or combination treatment. For non chemical plots, weed occurrence was rapidly increased with time in terms of number and weight. However no rice plot recorded the least increasing ratio. Similar trend was obtained at the herbicide plot even though the increasing ratio varied by herbicide properties. The least increasing ratio (1200 was recorded at the plot of butachlor/pyrazolate (5 days after transplanting, 5 DAT) followed by bentazon+propanil(25 DAT) while the greatest ratio (28%) was obtained from the plot of bifenox (5 DAT). In general, Scirpus hotarui, Eleocharis kuroguwai and Cyperus serotinus was gradually inereased with time by herbicide application, particularly at the butachlor/pyrazolate treatment. The community dominance and simpson index increased at the plot of bentazon and propanil due to increased of particular species while other herbicide plots exhibited reverse trend. Grain yield was curvilinearly decreased with weed weight for both times, 40 DAT and heading time eventhough the correlation coefficient of heading time was higher than 40 DAT.

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Characterization of Weed Occurrence in Protected Culture(P.E. house, P.E. tunnel, P.E. mulching) (시설재배지(施設栽培地)(P.E. 하우스, P.E. 턴넬, P.E. 멀칭)에서의 잡초발생특성(雜草發生特性))

  • Woo, I.S.;Pyon, J.Y.
    • Korean Journal of Weed Science
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    • v.8 no.3
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    • pp.317-323
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    • 1988
  • This survey was conducted to know characterization of weed occurrence under protected culture conditions at Yousong in 1985. Chenopodium album, Polygonum hydropiper, Portulaca oleracea and Digitaria sanguinalis were dominated in outdoor, whereas Capsella bursa-pastoris, C. album, D. sanguinalis and P. oleracea were dominant in polyethylene house. More weeds emerged in mulching plots and dry weight of weeds was greater in non-mulching plots. Summer broadleaf weeds and summer grasses were abundant in outdoor, whereas non-mulching plots in polyethylene house was dominated by winter broadleaf weeds, and mulching plots in polyethylene house were dominated by winter grasses and winter broadleaf weeds in early stage and summer grasses and summer broadleaf weeds in late stage. Simpson index was high in polyethylene house and Shannon's diversity index, maximum diversity for the Shannon diversity index were lower than eveness using the Shannon diversity index and this trend was more remarkable in mulching and mulching in tunnel than in non-mulching under polyethylene house condition. Shannon diversity index, maximum diversity for the Shannon diversity index were high in mulching or tunnel, and Simpson index was high in non-mulching in outdoor condition. Interspecific competition was more severe than intraspecific competition in both conditions.

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Faunal Assemblages of Benthic Macrofauna in the Inter- and Subtidal Region of the Inner Kyeonggi Bay, West Coast of Korea (서해 경기 내만해역 조간대, 조하대의 저서동물군집)

  • Shin, Hyun Chool;Choi, Jin Woo;Koh, Chul Hwan
    • 한국해양학회지
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    • v.24 no.4
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    • pp.184-193
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    • 1989
  • An investigation on the soft-bottom macrobenthic community in the inner Kyeonggi Bay was conducted in July, October of 1987 and February, May of 1988. The benthic fauna comprised a total of 87 species and showed mean density of 550 indiv./$m^2$. Major faunal groups are polychaetes, molluks, and crustaceans, corresponding to 64.7%, 17.4%, and 15.2% in total abundance respectively. The most abundant species was Tharyx sp. (10.9%), and followed by Mactra veneriformis (10.5%), Mediomastus sp. (8.6%), and Glycinde sp. (8.0%) etc.. The important species in the intertidal zone were Mactra veneriformis, Hinia festiva, and Nephtys californiensis, whereas those in subtidal channel region were Tharyx sp., mediomastus sp., Sternaspis scutata, and Nephtys polybranchia. The study area could be divided into 4 station groups based on the species composition; two groups within interidal flat and two in channel regions. Each station group sustained its specific benthic faunal assemblage; Mactra-Hinia, Aricidea-Haploscoloplos assemblages in the intertidal flat and Harpiniopsis-Urothoe, Mediomastus-Sternaspis assemblages in the subtidal channel region. The Mediomastus-Sternaspis assemblage showed the highest species number and population density, and also did the highest diversity and evenness indices. The Harpiniopsis-Urothoe assemblage showed the poor species composition and abundance, and so recorded the highest dominance index. Two assemblages in the intertidal flat had the intermediate values in all the biological parameters. The northern channel region of zone S-2 showed the high abundance in species composition, which seems to be caused by the heterogeneous sediment and the organic enrichment from the Han River and the Incheon industrial complex.

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Seasonal dynamics of phytoplankton community in the Anma Islands of Yeonggwang(AIY), West Sea, Korea (영광 안마군도 주변 해역 식물플랑크톤 군집의 계절 동태)

  • Hayeon Ju;Ayeong Song;Ji Hye Park;Yang Ho Yoon
    • Korean Journal of Environmental Biology
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    • v.40 no.1
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    • pp.70-86
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    • 2022
  • A survey was conducted to analyze seasonal dynamics of the phytoplankton community at 22 stations on the surface and bottom layers in the Anma Islands of Yeonggwang(AIY) in the southern West Sea, Korea from the spring of 2020 to the winter of 2021, using a marine survey vessel Ed Ocean. Based on the survey results, there were 87 phytoplankton species in 52 genera, diatoms accounted for 67.8%, dinoflagellates 26.5%, silicoflagellates 3.5%, and cryptomonads and euglenoids accounted for 1.1% each. By season, it was simple in spring and relatively varied in winter. The phytoplankton standing crop on the surface was low (28.8±30.1 cells mL-1) in summer and high (87.0±65.1 cells mL-1) in spring. In the phytoplankton community, diatoms showed a high share (over 80%) throughout the year, and Skeletonema costatum-ls was the dominant species with a dominance of more than 60% in spring and winter, and 34.6% and 24.2% in summer and autumn, respectively. The diversity expressing the characteristics of the community structure was high (2.79±0.45) in autumn and low (1.82±0.18) in spring, unlike the phytoplankton standing crop. However, the dominance was high at (0.86±0.08) in spring and low (0.44j0.13) in autumn. Based on the results of principal component analysis (PCA) using environmental and phytoplankton-related factors, it was estimated that the biological oceanographic environmental characteristics seen through the phytoplankton community in the AIY were dominated by nutrients supplied from open seawater and surface sediments by seawater mixing, such as tidal mixing.

Physical Environment Characteristics and Vegetation Structure of Natural Habitats of Pimpinella brachycarpa, Edible and Medicinal Plants (식·약용식물 참나물 자생지의 환경특성 및 식생구조)

  • Dae Hui Jeong;Yong Hwan Son;Hae Yun Kwon;Young Ki Kim
    • Korean Journal of Plant Resources
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    • v.37 no.2
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    • pp.137-148
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    • 2024
  • The purpose of this study is to investigate the weather, soil characteristics, and location environment of Pimpinella brachycarpa natural habitats in order to gather the essential information for the conservation of these habitats. P. brachycarpa are distributed throughout Korea and are mainly found to grow in shady and humid areas between 500 and 1,200 m above sea level. The average annual temperature in Mt. Duta was 13.1℃, and the average annual precipitation in Mt. Jungwon was 1,509 mm, which was higher than in other regions. The pH ranged from 4.42 to 4.97, indicating slight acidity. The total N content ranged from 0.18% to 0.68%, and the available P ranged from 13.43 to 531.56 mg/kg, demonstrating notable regional variations. The species diversity index (H') was highest at Mt. Ilwol, measuring 1.713. The evenness (J') ranged from 0.983 to 0.993, and the dominance (D') ranged from 0.007 to 0.017. The similarity index was very low, averaging 24.86%, and it was divided into communities of Wilson's elm (Ulmus davidiana var. japonica) and communities of Korean maple (Acer pseudo-siebodianum).

Species Composition of the Catches collected by a Bottom Trawl in the Southern Waters of Korea in Summer, 2004 (2004년 하계 한국 남해에 있어서 저층 트롤 어획물의 종조성)

  • Jeong, Sun-Beom;Hwang, Doo-Jin;Kim, Young-Ju;Shin, Hyeong-Ho;Son, Yong-Uk
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.41 no.1
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    • pp.35-45
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    • 2005
  • The experiment was conducted to investigate the species composition of catches collected by the bottom trawl on June 24 to 26, 2004 in the southern waters of Korea using a trawler "DONGBAEK" belongs to Yosu National University. The investigation was carried out at the 5 stations and the towing speed was 3.4${\sim}$3.7k't. The catches were composed of 46 species from 37 families, 10 orders and 2 classes for fishes and 2 species, 2 families and 2 orders for Chondrichthyes and 44 species, 35 familes, 8 orders for Osteichthyes. The catches of Perciforms were the highest as 24 species and 18 families for fishes. The catches of Spear squid, Loli해 bleekeri and Red banded lobster, Metanephrops thomsoni were also the highest for mollusca and crustacea as 1 class, 3 species, 3 families, 2 orders, 1 class and 7 species, 5 families, 1 order, 1 class respectively. In the 5 stations, number of individuals and biomass were 1,144 and 376.0kg at ST-1, 908 and 240.3kg at ST-2, 666 and 90.1kg at ST-3, 2,050 and 300..4kg at ST-4 and 561 and 24.7kg at ST-5. The diversity index of each stations ranged between 1.49 and it showed the richness index of 2.13${\sim}$3.48, the evenness index of 0.48${\sim}$0.77 and the dominance index of 0.43${\sim}$0.8. Body length distributio of the dominant specise were 9${\sim}$32cm(fork length) for Japanese horse mackerel, Trachurus japonicus, 7${\sim}$23cm(mantle length) for Common squid, Todarodes pacificus, 9${\sim}$43cm(mantle length) for Spear squid, Loli해 bleekeri, 23${\sim}$36cm(total length) for File fish, Thamnaconus modestus, 10${\sim}$28cm(fork length) for Yellow porgy, Dentex tumifrons, 10${\sim}$36cm(fork length) for Target dory, Zeus faber and 8${\sim}$35cm(fork length) for Red seabream, Pagrus major.

Biodiversity of Benthic Macroinvertebrate on Organic Rice Paddy Field (유기농업 논에서 저서성대형무척추동물의 다양성)

  • Kim, Jong-Sun;Kim, Do-Ik;Kim, Seon-Gon;Kang, Beom-Ryong;Ko, Suk-Ju;Lim, Gyeong-Ho;Kim, Hong-Jae
    • Korean Journal of Organic Agriculture
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    • v.17 no.2
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    • pp.193-209
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    • 2009
  • Total collected benthic macro invertebrates in rice paddy fields were identified 3 phylum, 5 class, 13 order, 25 family, 32 genera and 36 species, those in organic rice field were 12 order, 22 family and 28 species, and in conventional rice field were 10 order, 19 family and 25 species. The almost collected species inhabit lentic zone but Semisulcospira libertina, Corbicula fluminea, and Tipula sp. were habitat on lotic zone. The number of benthic macro invertebrates species was higher in organic paddy field than in conventional field. Eleven species were collected only on organic but eight species only on conventional field. The number of individuals were 870 on organic rice field which higher 3.6-fold on conventional field. The diversity indices of organic rice field were 1.57-2.45 and 0.71-2.61 in the first and second survey, respectively. The higher diversity indices, the lower dominance indices.

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Species Composition and Community Structure of Castanopsis cuspidata var. thunbergii Communities (모밀잣밤나무군락의 종 조성 및 군락구조)

  • Jung, Hye-Ran;Jeon, Kwon-Seok;Kim, Jong-Kab;Moon, Hyun-Shik
    • Korean Journal of Environmental Agriculture
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    • v.27 no.4
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    • pp.421-427
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    • 2008
  • This study was carried out to offer a basis data for application of effective management through species composition and community structure of Castanopsis cuspidata var. thunbergii stands (Bijindo and Yokjido). The upper, middle and lower layer in Bijindo and Yokjido consisted of 10, 11 and 27 species, and 9, 6 and 28 species, respectively. The importance value of Castanopsis cuspidata var. thunbergii were highest in upper and middle layer both two studied site. The herbaceous species were 33 and 47 species in Bijindo and Yokjido, respectively. The species diversity ranged from 0.523 to 1.280 in Bijindo and 0.699 to 1.364 in Yokjido. Dominance in Bijindo and Yokjido were 0.477 and 0.242 at upper layer, 0.231 and 0.102 at middle layer, and 0.106 and 0.057 at lower layer, which showed that Castanopsis cuspidata var. thunbergii stands are dominated by a large number of species at all layer. The distribution pattern by Morisita's index showed that Castanopsis cuspidata var. thunbergii was distributed randomly in upper layer both the studied sites.

Forest Community Classification and Stand Characteristics of Protected Area for Forest Genetic Resource Conservation in Mt. Cheongok (청옥산 산림유전자원보호구역의 산림군락분류 및 임분특성)

  • Shin, Jae-Kwon;Byun, Jun-Gi;Kim, Ju-Yeong;Choi, Seung-Ho;Kim, Dong-Kap
    • Proceedings of the Plant Resources Society of Korea Conference
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    • 2018.04a
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    • pp.47-47
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    • 2018
  • 본 연구는 청옥산 산림유전자원보호구역을 대상으로 총 49개의 고정방형구를 설치하여 식물사회학적 방법으로 산림군락분류와 임분특성을 분석하였다. 그 결과 총 9개의 식생단위로 분류되었으며 군락단위로는 신갈나무군락, 잣나무군락, 일본잎갈나무군락, 독일가문비나무군락으로 분류되었다. 신갈나무군락은 소나무군, 철쭉군, 고로쇠나무군, 미역줄나무군으로 세분되었으며, 고로쇠나무군은 박달나무소군과 고로쇠나무전형소군으로, 미역줄나무군은 애기감둥사초소군과 미역줄나무전형군으로 세분되었다. 9개의 식생단위의 층위별 중요치 분석결과를 보면 교목층에서 신갈나무가 32.2% 가장 높게 나타났으며 잣나무(10.1%), 소나무(10%), 일본잎갈나무(9.1%) 순으로 나타났고, 아교목층에서는 신갈나무 (18.9%), 당단풍나무(11.7%), 물푸레나무(8.9%), 잣나무(7.2%) 등이 높은 값으로 분석되었다. 관목층에서는 철쭉(12.2%)와 당단풍나무(8%)가 높게 분석되었으며 다른 수종들은 10% 미만의 값을 가졌다. 초본층에서는 조릿대(8.5%), 산숙국(6.6%)등이 높게 나타났다. 식생단위별 종다양성지수를 보면 식생단위 8인 일본잎갈나무군락이 1.76로 가장 높았으며, 박달나무소군 1.73, 소나무군 1.72, 철쭉군 1.71 순으로 분석되었다. 우점도는 모든 식생단위에서 0.2 이하로 다수의 종이 우점하는 것으로 나타났다.

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Leaf Feeding Insects of Welsh Onion and Shallot, and Their Species Abundance Patterns (대파 및 쪽파 잎기생 해충상과 종 빈도 분포형)

  • 고현관;최재승;엄기백;최귀문;김정화
    • Korean journal of applied entomology
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    • v.31 no.4
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    • pp.360-365
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    • 1992
  • Leaf feeding insect species of welsh onion and shallot were surveyed, and their species abundances were analyzed by fitness test for lognomal disstribution. A total of 13 and 6 species were identified on welsh onion and shallot, respectively. The dominant species on welsh onion were Thrips tabacid, Acrolepiopsis sapporensis, Spodoptera exigua, and Liriomyza chinensis. Thrips tabacid was also identified as the major species on the shallot. The community dominance was high in welsh onion and shallot observed on 12 October, Suwon. The species abundance patterns of the two communities were well described by lognormal distribution(P> 0.50).

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