• 수산경영론집
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• 제52권3호
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• pp.27-38
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• 2021

This study is aimed to figure out the productivity and variability of cage-aquaculture changes. According to the analysis, the productivity of major fish species has been increasing, except mullet. Although the regional productivity has decreased in the last two years, it has been on the rise considering as a whole. Gyeongsangnam-do showed the highest level of productivity by region. Productivity by species was also higher than other regions in the cases of rock fish, mullet and sea bream followed by productivity of Chungcheongnam-do. The production of marine cage-culture in Jeollanam-do is the second largest in Korea in value/weight while its productivity is lower than that of Chungcheongnam-do. When it comes to comparison by region, Gyeongsangnam-do shows the lowest productivity variation. And Jeollanam-do shows the second-lowest variation in productivity that is only about half of that of Chungcheongnam-do province. Thus, it is found that Jeollanam-do region has an advantage in management stability while its productivity is low. On the other hand, productivity by species was also analyzed. Gyeongsangnam-do has the highest productivity by species for rock fish, mullet and sea bream whereas rock bream productivity is the highest in Jeollanam-do. Therefore, it probably needs to reflect these results when choosing regional-focused incubation fish species.

• ALGAE
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• 제35권4호
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• pp.325-335
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• 2020

A new diatom species, Mayamaea vietnamica sp. nov., is described from Cát Tiên National Park in Vietnam. This species was discovered and described from soil samples. Algae from soil ecosystems in Vietnam are almost unknown. The new species is described on the basis of an integrated approach with molecular and morphological data, and comparison with similar species. In terms of molecular data, 18S rDNA (including V4 domain), and partial rbcL plastid genes show M. vietnamica sp. nov. is most closely related to M. terrestris N. Abarca and R. Jahn, and together they form a monophyletic group relative to other members of the genus. M. vietnamica sp. nov. differs from other species in the genus by the number of striae and areolae in 10 ㎛, number of areolae per stria, as well as shape and presence or absence of axial and central areas.

• 상하수도학회지
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• 제36권3호
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• pp.177-186
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• 2022

In this study, newly improved Ferron assay test haved on timed spectrometry was used for the determination of hyolrolytic Al species presented in PACl coagulant. The color development reagent ferron was prepared by using conventional method and two newly developed methods. Then the ferron assay test was used to compare and analyze the distribution of Al(III) hydrolyzed species presented in the prepared PACl and alum. The preparing method of reagent A required an aging period of 7 days by adding a hydroxylamine hydroxide and a 1,10-phenanthroline monohydrate reagent, whereas the preparing method of reagent B was used as a coloring agent immediately without aging time. The regression analysis between UV absorbance and Al concentrations of conventional method and newly developed method of ferron reagents in low-concentration aluminum solutions and high-concentration aluminum solutions, showed the correlation coefficients of 0.999 or higher, as showing high correlations of conventional method and newly developed method. Applying Ferron assay test, Al species in the PACls and alum were classified as Ala(monomeric Al), Alb (polymeric Al), and Alc (colloidal and precipitated Al). Distribution of Al(III) hydrolyzed species according to the preparation of ferron colorimetric reagents was similar.

• Journal of Species Research
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• 제12권3호
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• pp.203-211
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• 2023

Five ciliate species of Euplotes were isolated from fresh and coastal water during a sampling survey to identify unrecorded ciliates in South Korea. Their morphology was investigated using live observation, protargol and "wet" silver nitrate staining methods. Brief descriptions and microphotographs of each species and a comparison with related species are provided. Euplotes focardii is characterized by an average size of 65×47 ㎛ after protargol impregnation, 6 dorsal and 3 ventral ridges and dorsal argyrome pattern of double-eurystomus type. Euplotes nobilii shows an average size of 34×20 ㎛ after protargol staining, 6 dorsal and 3 ventral ridges and dorsal argyrome pattern of double-patella type. Euplotes octocarinatus, the only freshwater species described in the present study, is characterized by an average size of 66×46 ㎛ after protargol impregnation, 6 dorsal and 3 ventral ridges and dorsal argyrome pattern of double-patella type. Euplotes petzi has an average size of 43×30 ㎛ after protargol staining, a macronucleus hook-shaped and dorsal argyrome pattern in double-patella type. Euplotes raikovi is characterized by an average size of 40×24 ㎛ after protargol staining, 6 dorsal and 3 ventral ridges and dorsal argyrome pattern of double-patella type.

• 한국어류학회지
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• 제35권2호
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• pp.101-112
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• 2023

경남 통영시 풍화리 잘피밭에서 어류의 종조성 변동을 파악하기 위해 2021년 4월부터 22년 3월까지 지인망(surf net)을 이용하여 조사하였다. 10년전 수행된 선행연구 결과와의 비교에서 종조성과 우점종에 유의한 차이를 나타냈다. 또한, 선행연구에서 출현하지 않았던 아열대성 어종인 독가시치(Siganus fuscescens), 쏠종개(Plotosus lineatus), 두줄베도라치(Petroscirtes breviceps)가 출현하였다.

• 한국수산과학회지
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• 제47권3호
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• pp.264-273
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• 2014

To investigate species composition and seasonal variation of demersal organisms in the coastal waters off the Taean peninsula, otter trawl surveys were conducted from April 2010 to January 2011. A total of 75 species were collected, including 44 species of Pisces, 19 species of Crustacea, 6 species of Cephalopoda, 4 species of Gastropoda, and 1 species each of Bivalvia and Echinoidea. The dominant species in each season were Palaemon gravieri in spring, Charybdis bimaculata in summer, Loligo japonica in autumn, and Crangon hakodatei in winter. The number of species, individuals and biomass were highest in autumn and lowest in winter. The diversity index was highest in summer and lowest in winter. The dominance index was highest in winter and lowest in summer. The richness index was highest in autumn and lowest in winter. The evenness index was highest in summer and lowest in autumn. A cluster analysis showed that demersal organisms were divided into two groups; spring and winter organisms (Group 1) and summer and autumn organisms (Group 2). We detected a significant difference (P<0.05) between these groups, mainly owing to Platycephalus indicus, Repomucenus koreanus, and Paralichthys olivaceus within Pisces: Trachysalambria curvirostris, Metapenaeopsis dalei, P. gravieri, and C. hakodatei within Crustacea: and L. japonica within Cephalopoda.

• Journal of Forest and Environmental Science
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• 제38권2호
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• pp.90-101
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• 2022

The study aims to assess composition, diversity and population indices of natural regeneration of woody species in Jebel El Gerrie forest reserve, Blue Nile State, Sudan. We conducted field work between December 2018 and January 2019. We used random sampling to collect vegetation data in the forest where we made a total of 90 circular sample plots (radius 17.84 m) and distributed them proportionally to the area of each of the four density-based vegetation classes of the forest i.e. high density (C1), medium density (C2), low density (C3) and crop land (C4). In each sample plot we identified all regenerating tree species and counted their regeneration frequencies. We calculated ecological metrics of regeneration frequency, density, abundance, richness, evenness, diversity and importance value index (IVI) and drew abundance rank curve. Results revealed that out of fifteen mature tree species present, natural regeneration of 8 species, which belong to 6 families, was observed. The relatively most frequently naturally regenerating and abundant species were Anogeissus leiocarpa and Combretum hartmannianum. Richness, evenness and diversity of regenerating species were 1.33, 0.82 and 1.7, respectively. One-way ANOVA (α=0.05) of mean regeneration densities disclosed that there were significant differences (F_3,86=16.77, p=0.000) between C2 & C3 (p=0.000) and C2 & C4 (p=0.000). While regeneration of seven tree species were absent, two, two and four species were of good, poor and fair regeneration status, respectively. A comparison of mean density of natural regeneration with that of parent trees reflects a poor regeneration status of the forest. The study provides empirical results on the regeneration status of species and signifies the need for management interventions for species conservation and restoration, maintenance of biodiversity and sustainable production.

• Journal of Plant Biotechnology
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• 제48권1호
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• pp.18-25
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• 2021

멕시코로부터 유래한 Solanum demissum은 감자 야생종 중의하나로 감자 역병에 대해 저항성을 가지고 있어 감자 육종에서 중요한 재료로 이용되고 있다. S. demissum의 EBN은 4배 체인 감자와 같은 4로 직접적인 교배로 육종에 활용될 수 있다. 본 연구에서는 NGS 기술에 의해 완성된 S. demissum의 엽록체 전장 유전체(cpDNA)와 이를 다른 Solanum종과의 비교를 통해 개발한 분자마커에 대해 보고하였다. S. demissum의 전체 cpDNA의 크기는 155,558 bp였으며 그 구조는 다른 Solanum종과 매우 유사하였다. S. demissum의 cpDNA와 가지과에 속하는 10개 종의 cpDNA 코딩서열을 이용하여 분석한 계통수에서는 S. demissum이 S. hougasii 및 S. stoloniferum과 거의 동일한 유전체 구성을 보였으며, 다음으로 S. berthaultii 및 S. tuberosum과 유연관계가 가까운 것으로 확인되었다. S. demissum과 다른 7종의 Solanum과의 전체 cpDNA 다중 정렬을 통해 S. demissum 특이적인 두 개의 InDel 영역을 구명하였으며 이를 기반으로 최종적으로 PCR을 기반으로 한 두 개의 S. demissum 특이적 마커를 개발하였다. 본 연구의 결과는 Solanum 종들을 대상으로 한 조금 더 세부적인 진화적 그리고 육종적 측면에서의 연구에 기여를 할 수 있을 것이다.

• Fisheries and Aquatic Sciences
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• 제15권2호
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• pp.125-135
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• 2012

This study was carried out to understand the correlation between phylogenetic relationships based on 18S rDNA sequences and growth by salinity of Chlorella-like species. The 18S rDNA sequences of 71 Chlorella-like species which were mainly collected from Korean waters were analyzed. The 18S rDNA sequences of Chlorella-like species were divided into three groups (group A, B and C) and group B was further divided into three subgroups (subgroup B-1, B-2 and B-3). Thirty-seven Chlorella-like species in group A grew well at high salinity (32 psu) but the other groups grew well in freshwater. The sequence identities of the species in group A and B were 97.2-99.5%, but those of 6 species in group C ("Chlorella" saccharophila), which contained group I intron sequences region were 75.0-75.4%. Two representative species of each group were cultured at different salinities (0, 16 and 32 psu) to examine the correlation between the molecular phylogenetic groups and the phenotypic characteristics on cell growth and size by different salinities. The size of cell cultured at different salinities varied according to the species of each molecular phylogenetic group. The size of "Chlorella" saccharophila in group C was bigger and more obviously elliptical rather than that of the other Chlorella-like species. Considering the results on molecular and phenotypic characteristics, the group A and B belonged to Chlorellaceae, but group C was distinctly different from them.

• Applied Microscopy
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• 제24권4호
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• pp.13-31
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• 1994

피자식물내 엽육조직 미세구조연구의 일환으로 형태해부학적으로 매우 다른 특성을 지닌 국화과 Dubautia속 식물 3종(Dubautia scabra var. leiophylla, D. knudsenii, D. scabra var. leiophylla, D. knudsenii)의 엽육조직이 연구되었다. 부모종 엽육조직의 형태해부학적 특성과 그들의 잡종 엽육조직세포의 분화 정도를 추정하기 위하여 palisade mesophyll내의 chloroplasts, microbodies, mitochondria 및 grana내의 thylakoid membrane system, phytoferritin-like structures, plastoglobuli와 starch grain 등 엽록체 내부의 초미세구조 형질들을 중점적으로 비교 분석하였다. 잡종의 엽육조직세포들은 형태해부학적 엽육형질 및 thylakoidal membrane system 등의 형질에서 부모종 엽육조직의 중간적 특성 (intermediacy)을 나타내어 전형적인 bilateral inheritage를 보여주었으며, thylakoid membrane number/granum, phytoferritin-like structures, starch grain의 분포 등에서는 어느 한 부모종 형질과 더 유사하게 관찰되었다. 미소체 및 미토콘드리아는 대체로 비슷한 양상으로 관찰되었고 phytoferritin-like structures는 국화과 식물 엽록체내에서 처음 보고되는 미세구조이다.