• Title/Summary/Keyword: SPECIES NUMBER

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Yearly Fluctuation in the Fish Species Composition of Shrimp Beam Trawls off Maemuldo, Korea, during 2007-2009 (2007-2009년 매물도에서 새우조망에 의한 어류 종조성의 연변동)

  • Park, Jung-Youn;Kang, Hyun-Sook;Kang, Jung-Ha;Kim, Jin-Koo;Ryu, Jung-Hwa;Kim, Dong-Sun
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.46 no.5
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    • pp.619-625
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    • 2013
  • We investigated yearly fluctuation of the fish species composition of beam trawls off Maemuldo in the east southern sea of Korea, from March 2007 to November 2009. A total of 75 fish species were collected during the period. The number of fish species accumulated amounted to 54, 64 and 75 species in 2007, 2008 and 2009, respectively. The number of newly occurring species increased with time. The number of expected resident species in Maemuldo was estimated as 9 species including Conger myrister, Okamejei kenojei and Pholis nebulosa, each of which appeared more than 14 out of a total 27 times. Cluster analysis showed that the years 2007 and 2008 were closely clustered, while the year 2009 was distantly clustered with 2007 and 2008. This may be due to the high catch ratio of Clidoderma asperrimum in 2009 alone, when a low water temperature phenomenon was observed unlike the situation in 2007 and 2008.

Seasonal Variation of Abundance and Species Composition of Fishes Caught by a Set Net in the Coastal Waters off Yosu, Korea (여수연안 정치망 어획물의 종조성과 계절변동)

  • KIM Yeong Hye;KIM Jong Bin;CHANG Dae Soo
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.36 no.2
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    • pp.120-128
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    • 2003
  • Fishes were caught by a set net in the coastal waters off Yosu, Korea from April to October, 2001, and seasonal variation of abundance and species composition were studied. Fifty two species were identified as fish $(89\%)\;cephalopods\;(10\%)\;and\;crustaeans\;(1\%).$ Of the fishes Engraulis japonicus, Trachurus japonicus and Trichiurus lepturus were dominant species representing $64.1\%$ in total number of individuals. The number of species was high in spring and low in summer; number of individuals was high in spring and low in autumn. The diversity index (H') was 0.4-0.7 The abundance and species composition fluctuated seasonally. Occurrence of the various stages of fishes indicated that Scombia japonicus, T. japonicus and E japonicus utilized in the area as spawning ground, Conger myriaster larvae, Ammodytes personatus and Seriola quinqueradiata as nursery ground, and T. lepturus and Ilisha elongata as spawning and nursery grounds.

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.

Fish Assemblage in a Rocky Subtidal Habitat around Jam-do, Jinhae (진해 잠도 주변 암반해역의 어류상)

  • Kwak, Seok Nam;Park, Joo Myun
    • Korean Journal of Ichthyology
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    • v.28 no.4
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    • pp.273-278
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    • 2016
  • The seasonal variations in species composition and abundance of the fish assemblage were studied in the rocky subtidal habitat around the Jam-do, Jinhae. Fish samples were collected monthly from September 2007 to July 2008 using a pot. During study, a total of 48 fish species belonging to 24 families were collected. The dominant species were Sebastes longispinis, Pseudoblennius cottoides, Sebastes inermis, Rudarius ercodes, Ditrema temminckii, Ernogrammus hexagrammus, which accounted for 71.0% of the total number of individuals collected. The number of species, number of individuals, biomass and diversity greatly fluctuated showing a peak in the number of species, number of individuals and species diversity in autumn, whereas the biomass was the highest in spring. Abundance of dominant species varied with season. S. longispinis was abundant during spring and summer, while the abundance of P. cottoides was higher during autumn and spring. S. inermis occurred with high number in September, December and May, whereas R. ercodes occurred exclusively during autumn.

Effect of consecutive shoot-cutting for 3 years on saplings' sprouting regeneration ability of six deciduous oak species in Korea

  • Lee, Seung-Yeon;Cho, Kyu-Tae;Jang, Rae-Ha;You, Young-Han
    • Journal of Ecology and Environment
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    • v.41 no.3
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    • pp.66-71
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    • 2017
  • Background: The sprouts of oak species play an important role in maintaining the oak community in a disturbed environment. In this study, we cut 1-year-old oak in three times during the 3 years and measured the sprout responses to know sprouting ability of six deciduous oaks in Korea. Results: Oak sprouts have appeared in spring and fall, and some of the sprouts had lifespan as short as a month. As the number of cutting increases, sprout number of Quercus acutissima increased whereas the other oak species decreased or died. The average number of sprouts over the 3 years was from 1.4 (Quercus mongolica) to 2.2 (Q. acutissima) per individual. Quercus serrata died after the second cutting, and Quercus dentata died after the third cutting. So, the two species have the lowest sprouting ability among six oak species. The sprouts grew actively during fall and slowly in summer. The sprout length during the 3 years was in the following descending order: Q. acutissima, Quercus aliena, Q. dentata, and Q. mongolica. Sprout of Q. acutissima and Q. aliena generated steadily over the 3 years, and sprout of Quercus variabilis and Q. mongolica was changed by year. After the 3 years, the number of sprouts increased only in Q. acutissima but sprout number of the other five oak species decreased. The sprout length of Q. acutissima, Q. aliena, and Q. variabilis increased, but sprout length of the other three oak species decreased. The average survival rate of saplings over the 3 years was in the following descending order: Q. acutissima, Q. aliena, Q. variabilis, and Q. mongolica. Conclusions: As a result, the sprouting ability of Q. acutissima was the highest. Such level of sprouting ability may be the evidence of how Q. acutissima community exists as a dominant species in a disturbed environment in lowlands of Korea peninsula.

Species Compositon and Seasonal Variations of Fishes Collected by Winged Stow Nets on Anchors off Namhae Island (남해도 연안해역에서 낭장망에 의해 어획되는 어류의 종조성 및 계절변동)

  • Heo, Seong-Hoe;Gwak, Seok-Nam
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.34 no.3
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    • pp.309-319
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    • 1998
  • Species composition and seasonal variations of fishes collected by winged stow net on anchors in the coastal water off Namhae Island was studied from May 1989 m April 1990. During the study period, a total of 56 fish species were collected. Engraulis japonicus, Conger myriaster, Trichiurus lepturus, Sardinella zunasi, Ammodytes personatus, and Thryssa kammalensis predominated. These six species accounted for 93.9% of the total number and 81.3% of the total biomass of fishes collected. Fishes collected by winged stow nets on anchors were primarily small fish species or early juveniles of large fish species. Both abundance and species composition of fishes changed with season. Seasonal peaks of number of species occurred in spring and fall, while those of number of individuals and biomass occurred in spring. The lowest number of individuals and biomass were observed in winter. Low species diversity indices were observed in summer. These low diversity indices in summer were mainly due to predominance of E. japonicus which accounted for approximately 90% of all fishes collected. More species and greater biomass were collected during nighttime.

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Study on Community Structure and Seasonal Variations of Coleoptera in Mt. Yeonyeop area, Korea (연엽산 일대 딱정벌레목의 군집구조 및 계절적 변동에 관한 연구)

  • Lee Seung-Il;Jeong Jong-Kook;Choi Jae-Seok;Kwon Oh-Kil
    • Korean Journal of Environmental Biology
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    • v.23 no.1
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    • pp.71-88
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    • 2005
  • This study has been monthly carried out to investigate the community structure and seasonal variations of Coleoptera from April to September, 2004 in Mt. Yeonyeop area, Gangwon-do, Korea. A total of 3053 individuals belonging to 358 species in 49 families have been collected in the studied area by light trap, pitfall trap and sweeping methods. The abundant families, based on the number of species, were Carabidae (50 species), Chrysomelidae (40 species) and Curculionidae (40 species). The number of species were highest at site 4, located in low altitude and contained stream. The number of individuals were highest at site 2, because many beetles were attracted by pitfall traps. The total number of species and individuals was highest in July. Nicrophorus (Nicrophorus) quadripunctatus (13.00%) was a dominant species and Synuchus (Synuchus) cycloderus (7.17%) was sub dominant species. Especially Damaster mirabilissimus mirabilissimus, a protected species by government, was collected in May.

Analysis of the Correlation Between Ecological Status and Location Environment by Cultivated Land Restoration Type of Geumgang Riverine Ecobelt

  • Lee, Soo-Dong;Back, Seung-Jun;Kang, Hyun-Kyung
    • Journal of People, Plants, and Environment
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    • v.24 no.4
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    • pp.389-401
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    • 2021
  • Background and objective: The purpose of this study is to investigate the ecological status of six areas around Geumgang River that used to be farmlands before they were restored as a riverine ecobelt. This study aims to analyze the correlation between the location environment and ecological status of the sites to identify the environmental factors affecting them. Methods: The sites are classified into four types according to restoration: terraced paddy fields, flat paddy fields, artificial wetland, and landscape forest. The survey items were divided into land use status, plant ecology, and animal ecology. Results: In terms of plant ecology, terraced paddy fields showed favorable naturality with the rate of native species above 90% and the naturalization index below 10%. In terms of animal ecology, the total number of species found in these areas was biggest in terraced paddy fields, followed by flat paddy fields, artificial wetland, and landscape forest. Regarding species diversity, terraced paddy fields also showed abundant species with an average of 1.05 to 1.09. The results of the correlation analysis showed that the forest area around the sites had the most significant effect on species diversity. The grassland and open water area showed a positive correlation with the total number of animal species and the number of dragonflies, confirming that the marshy grassland had a positive effect. As the cultivated land and urbanized area around the sites increased, it had a negative effect on the distribution of native species and the number of animal species that appeared, and a positive effect on the naturalization index. Conclusion: It is necessary to establish preemption and restoration plans for sites such as grasslands adjacent to the forest and terraced paddy fields in order to promote resilience of the diverse species returning to the purchased lands.

Plot Size for Investigating Forest Community Structure (IV) - Adequate Number of Plots for Shrub Stratum in a Mixed Forest Community of Abies holophylla and Broad-leaved Trees at Odaesan National Park - (삼림군집구조 조사를 위한 조사구 크기에 관한 연구(IV) - 오대산 국립공원지역 젓나무-활엽수 혼효림군집 관목층의 적정 조사구수 -)

  • 박인협;문광선
    • Korean Journal of Environment and Ecology
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    • v.9 no.2
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    • pp.197-201
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    • 1996
  • A mixed forest community of Abies holophylla and broad-leaved trees in Odaesan National Park was studied to determine the adequate number of plots of shrub stratum for investigating forest community structure. Thirty 5m*5m plots were set up in the shrub stratum, and species-area curve and performance curve were made out. The minimum number of plots where a given percentage increase in number of plots produce in number of plots produced less than the same percentage increase in number of species was six. The minimum number of plots where a given percentage increase in number of plots produced less than the half of the percentage increase in number of plots was eleven. The minimum number of plots where the dominant species was distinguished from the subdominant species was five. The minimum numver of plots where the first subdominant species was distinguished from other subdominant species was ten. The diffrence of species diversity(H') between five or more plots and total thirty plots was less than 0.05. Similarity index was more than 70% between five or more plots and total thirty plots, and more than 80% between ten or more plots and total thirty plots. The conclusion is that the adequate number of 5m*5m plots for the shrub stratum was about 5 in general case and about 10 in case of requiring more accuracy.

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Study on Minimum Viable Population of Seed Bank in Pine Forest (소나무림 매토종자 최소생존가능개체군에 관한 연구)

  • Yi, Myung-Hoon
    • Korean Journal of Environment and Ecology
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    • v.32 no.5
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    • pp.497-506
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    • 2018
  • The purpose of this study was to investigate the proper minimum viable population of a seed bank for the ecological restoration of pine forest using a seed bank. It examined the germinated soil seed bank from August 2010 to November 2011. The results of the correlation analysis showed that the area and the number of herbaceous species were the highest at 0.686. The results of the regression analysis of four variables including the number of woody species, the number of woody individuals, the number of herbaceous species, and the number of herbaceous individuals using the theory of island biogeography to the minimum viable population in studied plots showed that all four variables were significant with area at the level of 0.05, and R square was 0.583. One function was selected between the number of species and the number of individuals from the canonical correlation analysis, and the function square was 0.824. Both canonical function and squared canonical correlation showed significant at the level of 0.01. The result of study recommended the area size of the minimum viable population in pine forest applied by seed bank to be larger than $64m^2$, the number of species to be over 21, and the number of population to be over 120. It also found that the number of herbaceous species determined the cluster size of the seed bank. Therefore, it is necessary to consider herbaceous species that appear in the seed bank.