• Title/Summary/Keyword: Species composition and structure

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Role of Energy and Composition of Film-Forming Species in Formation of Composition and Structure of Compound Films

  • Shaginyan, L.R.
    • Journal of the Korean institute of surface engineering
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    • v.34 no.5
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    • pp.455-464
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    • 2001
  • Effect of bombardment of the growing film by energetic particles on its properties is know over many years and is widely used for modification of the film properties. Despite of this there are no final answers on such questions as: what is the mechanism of compositional changes that take place for some compound films deposited under the ion bombardment, how the ion bombardment influences the epitaxial growth, what mechanisms govern the growth of the film on its early stages during deposition under the ion bombardment. The role of composition of film-forming species in formation of film structure is barely investigated or even not investigated at all. Experimental evidence and discussion of the influence of ion bombardment and composition of film-forming species on structure and composition of compound films are briefly considered in the review.

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Species Composition and Community Structure of Demersal Fish Caught by a Danish Seine Fishery in the Coastal Waters of the Middle and Southern East Sea, Korea (동해구외끌이중형저인망에 의한 동해 중남부 해역 저어류의 종조성 및 군집구조)

  • Sohn, Myoung Ho;Park, Jeong-Ho;Yoon, Byoung Sun;Choi, Young Min;Kim, Jin-Koo
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.48 no.4
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    • pp.529-541
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    • 2015
  • We examined the species composition and community structure of demersal fish in the middle and southern coastal waters of the East Sea of Korea by surveying a commercial Danish seine fishery from 2010 to 2013. We considered the waters north of $37^{\circ}N$ as middle and those south of $37^{\circ}N$ as southern waters. A total of 79 demersal fish species belonging to 18 families were collected. Of these, 59 species (77.6%) inhabited only the East Sea as opposed to the West and South Seas of Korea, and most were resident species. The species and biomass were similar between the two portions of the study area. The sandfish Arctoscopus japonicus (78.0%) and the blackfin flounder Glyptocephalus stelleri (65.1%) were the most common species and accounted for the most biomass in the middle and southern waters, respectively. Fish were most abundant at shallow depths (50-100 m) in the middle portion of the East Sea. Using a cluster analysis, we divided the species composition and community structure at the sampling stations into three groups: middle portion (group A), deep area of the southern portion (group B), and shallow areas of the southern portion (group C). A. japonicas and G. stelleri were dominant in groups A and B, while G. stelleri and Clupea pallasii were dominant in group C.

Species composition and community structure of benthic crustacean assemblage around Oryukdo in southeastern waters off Korea (오륙도 주변해역 저서 갑각류 (Crustacea)의 종조성과 군집구조)

  • Heo, Yu-Sim;Choi, Jung-Hwa;Kim, Jung-Yun;Lee, Dong-Woo
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.50 no.4
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    • pp.604-613
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    • 2014
  • Community structures and species composition in benthic crustacean around Oryukdo of Busan was investigated using a SCUBA diving in 2011. A total 115 species, 51 families, and 4 taxa were collected during the sampling periods. Species were included 52 species in amphipoda, 49 in decapoda, 8 in isopoda and 6 in thoracica. On cluster analysis, the benthic crustacea community was classified into three groups based on the species composition: group A occurred in spring, group B in autumn and winter and group C in summer. Species composition in benthic crustacean corresponded with the water temperature.

Species composition and community structure of aquatic organisms caught by the coastal beam trawl in the Gomso Bay, Jeollabuk-do of South Korea (전라북도 곰소만 연안조망에 어획된 수산생물의 종조성 및 군집구조)

  • Young-Hwan JOO;Sang-Chul YOON;Ji-Hoon CHOI;Myounghee KANG;Jin-Koo KIM;Hyun-Su JO
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.60 no.2
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    • pp.101-113
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    • 2024
  • This study investigated the species composition and community structure of aquatic organisms captured using coastal beam trawling in Gomso Bay, Jeollabuk-do, from January to December 2022. Throughout the experimental period, a total of 20,246 individuals belonging to 94 marine species were captured, with a combined biomass of 602,828 g. Fish exhibited the highest abundance, comprising 56 species, followed by crustacea (21 species), bivalvia (8 species), cephalopoda (5 species), gastropoda (3 species), and holothuroidea (1 species). The dominant species was Leiognathus nuchalis, constituting 14.0% of the total individuals, followed by Portunus trituberculatus at 12.1%, Oratosquilla oratoria at 10.4%, Crangon hakodatei at 9.9%, and Metapenaeus joyneri at 7.9%. The diversity index ranged from 1.72 to 2.55, with the lowest diversity observed in March and the highest in July. Cluster analysis based on species composition of the 27 most common species showed that aquatic organisms were divided into three groups: spring and summer organisms (Group A) and summer organisms (Group B) and autumn and winter organisms (Group C).

Biodiversity and Community Structure of Marine Benthic Organisms in the Rocky Shore of Dongbaekseom, Busan

  • Yoo, Jong-Su
    • ALGAE
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    • v.18 no.3
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    • pp.225-232
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    • 2003
  • Species composition, community structure and biodiversity of marine benthic community were studied in the rocky shore of Dongbaekseom, Busan. A total of 82 species of marine algae including 4 Cyanophyta, 11 Chlorophyta, 20 Phaeophyta and 47 Rhodophyta are listed. The dominant algal species were Ulva pertusa, Chondria crassicaulis, Corallina spp. and Melobesioidean algae. Sargassum thunbergii, Chondracanthus intermedia, Gelidium divaricatum and Ralfsia verrucosa were subdominant in cases of different seasons and vertical layers. Chthamalus challengeri, Littorina brevicula and Mytilus edulis were dominant zoobenthic species upper-middle layer of the intertidal zone. The community structure of this area seemed to be controlled by spatial competition with benthic marine algae. The species diversity indices estimated from different sources were quite different. Indices from coverage were 1.87, 3.98 from frequency, 2.26 from the average of total frequency and coverage and 2.15 from importance value. The similarity indices on the present study showed decreasing trends comparing to the previous benthic algal composition researches.

Forest Structure and Composition in the Vicinity of Srinagar Hydroelectric Power Project in Alaknanda Valley, Garhwal Himalaya, India

  • Ballabha, Radha;Kuniyal, Archana;Tiwari, Prabhawati;Tiwari, Jay Krishan
    • Journal of Forest and Environmental Science
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    • v.36 no.2
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    • pp.78-90
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    • 2020
  • We studied forest structure and composition in the vicinity of Srinagar Hydroelectric Power Project in Alaknanda Valley, Garhwal Himalaya, India to provide baseline data for the management of forests. Eight sites were selected in the vicinity of power project based on elevation and species composition. Density varied from 650 to 340 ind ha-1 for trees and from 4,360 to 6,480 ind ha-1 for shrubs. TBC ranged from 35.02 to 54.02 ㎡ ha-1 for trees and from 0.875 to 2.628 ㎡ ha-1 for shrubs. On the basis of density and IVI, Pinus roxburghii was found dominant tree species in most of the sites, whereas among the shrubs, Carissa opaca was dominant. Dominance of Pinus roxburghii in most of the sites is an indication towards possible threat to associated species in the area. The dominance-diversity curve of trees showed a geometric distribution, whereas the shrubs displayed log-normal curves. The forest has rich and diverse species composition however; habitat degradation caused by the construction of Power Project might lead to reduction of plant species from the area. The information obtained from this study will be helpful in predicting possible changes in the forest ecosystem properties in near future after completion of the power project.

Species Composition and Community Structure of Fishes Collected by a Gill Net in the Coastal Waters of the Geumo Islands, Yeosu (여수 금오열도 연안 자망에 채집된 어류의 종조성 및 군집구조)

  • Kim, Chun-Cheol;Han, Kyeong-Ho;Lee, Sung-Hoon;Yu, Tae-Sik
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.50 no.5
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    • pp.553-560
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    • 2017
  • Fluctuations in the abundance and species composition of fishes in the coastal waters of Geumo-do, Yeosu, Jeollanam-do, Korea were investigated from 2002 to 2005. A gill net with entrances on both sides was used to collect a total of 469 individuals (55,180 g) of 3 orders, 18 families, and 28 species. The dominant species was Sebastes inermis (60 individuals, 5,670 g), followed by Neoditrema ransonneti (46 individuals, 2,290 g), and Pseudaesopia japonica (38 individuals, 3,080 g). The highest number of individuals was found in 2004, while the biomass was highest in 2005. The diversity index was highest in 2004 (H'=2.703) and lowest in 2002 (H'=2.580). The dominance index was highest in 2004 (D=3.983) and lowest in 2002 (D=3.404). The richness index was highest in 2003 (RI=0.337) and lowest in 2002 (RI=0.261). Changes in temperature and salinity affected the community structure and the location of spawning grounds. The number of individuals and total biomass increased with changes in temperature and salinity each year.

Composition and Abundance of Wood-Boring Beetles Inhabited by Pine Trees

  • Park, Yonghwan;Jang, Taewoong;Won, Daesung;Kim, Jongkuk
    • Journal of Forest and Environmental Science
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    • v.35 no.3
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    • pp.189-196
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    • 2019
  • Plants are consumed by a myriad of organisms that compete for resources. Direct interactions among multiple plant-feeding organisms in a single host can range for each species from positive to negative. Wood-boring beetle faces a number of biotic and abiotic constraints that interfere with the good prospects from the tree. Biotic factors, including arthropod pests and diseases, and abiotic factors, such as drought and water-logging, are the major constraints affecting the species. The present study aimed to provide basic data for analyzing forest health, identify the kinds of wood-boring beetles in the central part of Korea. Our second goal was to analyze the species composition and diversity of regional communities and to examine. A total of 10,461 individual wood-boring beetles belonging to 8 families and 50 species attracted to trap trees in the pine forests were recorded during the study period on study sites. The results of the analysis of collected species showed that the community structure on all study sites was similar. Seasonal occurrences of dominant wood-boring beetles (5 species) from each study site showed the highest number of all species, except for Siphalinus gigas in May, followed by a gradual decline, and the largest number of Siphalinus gigas appeared in June. The similarity index of species composition was relatively high, ranging from 0.75 to 0.90 for each study site.

Species composition of the catches collected by trammel net in the coastal waters off Ulleungdo of Korea (울릉도해역에서 삼중자망에 의한 어획물의 종조성)

  • CHUNG, Sangdeok;CHA, Hyung Kee;LEE, Jae Bong;LEE, Hae Won;YANG, Jae Hyeong
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.51 no.4
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    • pp.567-575
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    • 2015
  • Species composition in the coastal waters off Ulleungdo of Korea were examined based on catches bimonthly collected by trammel net in 2013. A total of 711 individuals and 181.9 Kg were caught and catches were composed of 4 classes 15 orders 27 families 52 species including 44 Pisces, 4 Gastropoda, 3 Cephalopoda, and 1 Echinodermata. The dominant species in biomass were File fish (Thamnaconus modestus), Atka mackerel (Pleurogrammus azonus), and Greenling (Hexagrammos otakii). Data were summarized using hierarchical cluster analysis (HCA) and detrended correspondence analysis (DCA) to examine similarity in species composition for each month, and community structure in Ulleungdo was divided into two groups. Community structures in February, April and December with low temperature and well-mixed surface water were distinguished from those in June, August and October with high temperature and strong stratification, which could be attributed to temporal changes in dominant species. Atka mackerel and Spear squid mainly caught in February and April, disappearing in June, August and October, and File fish outburst was shown in October. Because the water off Ulleungdo has been under low human pressure, it could be a good case study to elucidate effects of climate change on community structure and ecosystem in the East sea. Continuous surveys and further studies are required to demonstrate migration route and distribution of dominant species and long-term changes in community structure in the water of Ulleungdo.

Species Composition and Stand Structure of Natural Forest, Timber-harvested Forest and Degraded Forest in the Bago Yoma Region of Myanmar

  • Oo, Thaung Naing;Lee, Don Koo
    • Journal of Korean Society of Forest Science
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    • v.96 no.5
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    • pp.572-579
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    • 2007
  • Tree species diversity is an important aspect of forest ecosystem stability. Tree species inventories at defined sites and in minimum diameter classes give a reliable indicator of the diversity level as well as the structural stability level of a study site. This study was conducted to investigate the species composition and the stand structure of the natural forest, timber-harvested forest (logged-over forest) and degraded forest of the Oak-twin Township in the Bago Yoma Region of Myanmar. Natural forest showed the highest family and species richness in all the investigated forests. At the family level, Verbenaceae occupied the highest importance value index (IVI) in all the forest stands while teak (Tectona grandis Linn. f.) occupied the highest IVI at the species level. However, the small diameter classes of T. grandis and other commercial species were less than those of big diameter classes in all the investigated forests. This abnormal pattern of diameter distribution could be a problem for the sustainable production of commercial timber species in the near future.