• Journal of Forest and Environmental Science
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• v.38 no.3
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• pp.141-151
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• 2022

Soil seed banks as natural storage of plant seeds play an important role in the maintenance and regeneration of watershed. Natural regeneration potential of the soil seed bank of Land use types (LUTs) in Ogun River watershed (ORW) was investigated. ORW was stratified using proportionate sampling technique into Guinea Savannah (GS), Rainforest (RF) and Swamp Forest (SF) Ecological Zones (EZs). Three LUTs: Natural Forest (NF), Disturbed Forest (DF) and Farmland (FL) were purposively selected in GS: GSNF, GSDF, GSFL; RF: RFNF, RFDF, RFFL and SF: SFNF, SFDF, SFFL, respectively. Systematic line transects was used in the laying of the sample plots. Sample plots of 25 m×25 m were established in alternate positions. Ten 1 m×1 m quadrats were randomly laid for soil core sampling from previously randomly selected ten plots. The core samples (10) were pooled per plot in each LUT and placed in individual trays. Ten trays with sterilized soil were used as control. The trays were watered regularly and checked for seedlings emergence fortnightly for 18 months. The experimental design used was 3×3 factorial experiments. ANOVA, Diversity index (H') and Similarity index (SI) were used to analyze the data. There was significant difference in seedling emergence among ecological zones and land use types (p<0.05). A total of 4,400 seedlings emerged from the soil samples. All species were distributed among 32 families. FL in the RF had the highest number of germinated seeds (705±37.33 seedlings) followed by DF in the RF (701±49.6 seedlings). The lowest emergence was in NF of the SF (199±28.41 seedlings). DF in the RF had highest number of species (34) distributed among 22 families. Emergence from soil seed bank of NF in ORW was generally with more of tree species than herbs that were predominant in FL and DF.

• Korean Journal of Soil Science and Fertilizer
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• v.29 no.2
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• pp.165-172
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• 1996

Symbiotic effectiveness and significance of Bradyrhizobium japonicum strains in five serogroups which were consisted of three corresponding serotype strains, respectively, indigenous to Korean soils were evaluated in terms of utility of strain serogroup for symbiotic improvement on soybean plant. The nodulation by rhizobia of each serogroup on four soybean cultivars(Danweonkong, Kwangkyo, Pangsakong, and Eunhakong) was good in order of USDA 123 > YCK 150 > YCK 117 > YCK 141 > USDA 110 serogroup members. Shoot dry weight of soybean was relatively high with USDA 110 serogroup members as well as with YCK 141 serogroup members, whereas the effectiveness of USDA 123 serogroup members was the lowest among the serogroups examined. In particular, Pangsakong among soybeans inoculated with five-serogroup members was positively outstanding on nodulation and shoot dry weight of the plant. Overall, symbiotic parameters of serogroup members associated with soybean plant such as nodule number, nodule mass, $N_2$ase activity, and shoot dry weight showed significantly different responses at level of 1% probability among both rhizobial serogroups and soybean cultivars, respectively. The rate in symbiotic similarity of the members of each serogroup from F-test ($$P{\leq_-}0.05$$) was 100% for nodule No., 90% for $N_2$ase activity. and 80% for soybean shoot dry weight. Taken together, the results indicated that the serological grouping of B. japonicum could be strongly useful for improving the symbiotic effectiveness hetween soybean and Rhizobium.

• Korean Journal of Environmental Biology
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• v.32 no.4
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• pp.286-296
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• 2014

In this study, we investigated the macrobenthic community structure and spatiotemporal variations in Uljin Marine Ranching area, East Sea of Korea. Macrobenthos were collected using a modified van Veen grab sampler from April to September 2013. Total number of species sampled was 345 and mean density was 5,797 ind. $m^{-2}$, both of which were dominated by the polychaetes. The most dominant species were Spiophanes bombyx (53.64%), followed by Magelona sp.1 (6.96%), Cadella semitorta (2.73%), Lumbrineris longifolia (2.16%) and Alvenius ojianus (2.08%). Cluster analysis and nMDS ordination analysis based on the Bray-Curtis similarity identified 2 station groups. The group 1 (station 2, 3, 5, 6, 8 and 9) was characterized by high abundance of the polychaetes Magelona sp.1, Lumbrineris longifolia, Scoloplos armiger, Praxillella affinis, Maldane cristata and the bivalve Alvenius ojianus, with fine sediment above 30m water depth. On the other hand, the group 2 (station 1, 4, 7 and 10) was numerically dominated by the polychaete Lumbrineriopsis sp. and the bivalve Cadella semitorta, with coarse sediment below 5m water depth. Collectively, the macrobenthic community structure showed a distinct spatial trend, which seemed to be related to the water depth and sediment composition.

• Korean Journal of Medicinal Crop Science
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• v.10 no.3
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• pp.194-199
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• 2002

Extracted genomic DNA from 16 accessions of Codonopsis lanceolata collected from South Korea and the Baekdoo Mt. areas of China were analyzed for their genetic relationships by RAPD. Twenty 10-mer-oligonucleotide primers having reproductive polymorphism were selected for the RAPD analysis. The size of amplified DNA was almost between 125 bp and 2.0 kbp. Sixteen collected Codonopsis lanceolata were analyzed with 20 primers which generated 73(49.3%) polymorphic bands among 148 PCR products. The mean number of polymorphic bands were 7.4 and varied $1{\sim}9$ per primer. It was, thus, demonstrated that RAPD was useful for detecting polymorphism in Codonopsis lanceolata. The range of 1-F value(genetic similarity) was from 0.682 to 0.959. These results indicate variable genetic similarities. By UPGMA (Unweighted Pair Group Method using an Arithmetic average) cluster analysis based on 1-F value, genetic distance among the 16 collected Codonopsis lanceolata was $0.133{\sim}0.400$. It was certainly classified into two groups between collected accessions from Korea and China, and the genetic distance was about 0.281. Both accessions collected from Korea and China showed miner differences, while the genetic relationships of Tonghua Xian and Liuhe Xian from China was farthest with other accessions collected.

• Journal of Korea Water Resources Association
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• v.44 no.12
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• pp.929-940
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• 2011

In this study, the future expected discharges are analyzed for Daecheong and Yongdam Dam Watershed in Geum River watershed using A1B scenario based RCM with 27 km spatial resolutions from Korea Meteorological Agency and SWAT model. The direct use of GCM and RCM data for water resources impact assessment is practically hard because the spatial and temporal scales are different. In this study, the problems of spatial and temporal scales were settled by the spatial and temporal downscaling from watershed scale to weather station scale and from monthly to daily of RCM grid data. To generate the detailed hydrologic scenarios of the watershed scale, the multi-site non-stationary downscaling method was used to examine the fluctuations of rainfall events according to the future climate change with considerations of non-stationary. The similarity between simulation and observation results of inflows and discharges at the Yongdam Dam and Daecheong Dam was respectively 90.1% and 84.3% which shows a good agreement with observed data using SWAT model from 2001 to 2006. The analysis period of climate change was selected for 80 years from 2011 to 2090 and the discharges are increased 6% in periods of 2011~2030. The seasonal patterns of discharges will be different from the present precipitation patterns because the simulated discharge of summer was decreased and the discharge of fall was increased.

• Journal of Korea Water Resources Association
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• v.41 no.2
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• pp.212-228
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• 2008

Five representative reference evapotranspiration(RET) equations were selected, and these equations were compared with pan evaporation by correlation analysis. Pan coefficients were also estimated. Furthermore, five selected RET equations were compared to find the similarity among those at the 21 meteorological stations located in South Korea. Five RET equations selected from 4 different category were Penman(combination approach), FAO Penman-Monteith(FAO P-M) (single source approach), Makkink and Priestley-Taylor (radiation approach) and Hargreaves(temperature approach) equations. In this study, the geographical and topographical conditions were considered for the selection of study stations. The daily meteorological data measured from 1970 at an interval of 5 years were applied in this study. The evapotranspiration estimates obtained by applying evapotranspiration equations were evaluated with numerical and graphical methods. The correlation coefficients between pan evaporation and RET in study stations were above 0.9 indicating very high correlation; however, the slopes of the individual regression lines show the values greater or less than 1.0. Hargreaves equation(temperature approach) shows the most similar evapotranspiration estimates to those of FAO P-M equation from 12 study stations, which are located near to seashore except Daegu station. On the other hand, Priestley-Taylor equation(radiation approach) shows the most similar evapotranspiration estimates to those of FAO P-M equation from 8 study stations, which are located in inland.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.52 no.4
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• pp.372-385
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• 2016

This present study investigated characteristics of distribution and community structure of macrobenthic invertebrates through the survey of commercial Danish seine fisheries from 2011 to 2013. In this study, a total of 28 species were sampled with a mean density of $32,568ind./km^2$ and mean biomass of $1,649.5kg/km^2$. The dominant species, comprising over 1.0% of the total number of individuals, were Chionoecetes opilio ($11,203ind./km^2$, 34.4%), Pandalus eous ($9,247ind./km^2$, 28.4%), Ophiuridae spp. ($5,750ind./km^2$, 17.7%), Argis lar ($2,631ind./km^2$, 8.1%), Neocrangon communis ($994ind./km^2$, 3.1%), Berryteuthis magister ($612ind./km^2$, 1.9%), Sepiola birostrata ($499ind./km^2$, 1.5%) and Strongylocentrotidae sp. ($424ind./km^2$, 1.3%). The dominant species, in terms of biomass, comprising over 1.0% of the total biomass, were C. opilio ($1,167.2kg/km^2$, 70.8%), B. magister ($130.3kg/km^2$, 7.9%), P. eous ($102.4kg/km^2$, 6.2%), Ophiuridae spp. ($84.6kg/km^2$, 5.1%), Enteroctopus dofleini ($45.5kg/km^2$, 2.8%), A. lar ($35.7kg/km^2$, 2.2%), Strongylocentrotidae sp. ($25.0kg/km^2$, 1.5%) and S. birostrata ($22.1kg/km^2$, 1.3%). Among them, S. birostrata, E. dofleini, Strongylocentrotidae sp. and Ophiuridae spp. were higher abundance and biomass in the shallow water (<200 meters in depth), whereas C. opilio, P. eous, A. lar, N. communis and B. magister were higher in the deep water (301 ~ 500 meters in depth). As the results of cluster analysis and non-metric multidimensional scaling (nMDS) analysis based on the Bray-Curtis similarity of fourth root transformed data for number of species and individuals, the macrobenthic invertebrates community by Danish seine survey was divided into two groups of station in the shallow water (<200 meters in depth, Group A) and the deep water (201 ~ 500 meters in depth, Group B). The major individual-dominant species was S. birostrata, Ophiuridae spp. and immature C. opilio in group A. But Group B was P. eous, A. lar, B. magister and mature C. opilio.

• Journal of Life Science
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• v.23 no.3
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• pp.406-414
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• 2013

The influence of a gradual increase in salinity on the diversity of aquatic bacterial in rivers was demonstrated. The denaturing gradient gel electrophoresis (DGGE) was used to analyze the bacterial community shift downstream in the Hyeongsan River until it joins the open ocean. Four water samples were taken from the river showing the salinity gradients of 0.02%, 1.48%, 2.63%, and 3.62%. The samples were collected from four arbitrary stations in 2.91 km intervals on average, and a DGGE analysis was performed. Based on the results of this analysis, phylogenetic similarity identification, tree analysis, and a comparison of each station were performed. The results strongly suggested that the response of the bacterial community response was concomitant to gradual changes in salinity, which implies that salt concentration is a major factor in shifting the microbiota in aquatic habitats. The results also imply a huge diversity in a relatively small area upstream from the river mouth, compared to that in open oceans or coastal regions. Therefore, areas downstream towards a river mouth or delta are could be good starting points in the search for new bacterial species and strains ("biotypes").

• Korean Journal of Medicinal Crop Science
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• v.10 no.1
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• pp.17-23
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• 2002

The seeds of Coix lachryma-jobi Linne var. mayuen Stapf. are used as dietary food for obesity and diabetes under the names of Yulmu in Korea and Yiyiren(薏苡仁) in China. It is one of the drugs promoting diuresis to eliminate the wetness-evil from the lower warmer in the traditional Korean medicine. According to ancient textbook of the traditional Korean medicine, it should be applied to patients with phlegm and heat, etc. The establishment of the method for the discrimination of Coisis Semen is very important for the quality control of drugs. Random amplified polymorphic DNA(RAPD) analysis and anatomical characteristics were used for the discrimination of Coix lachryma-jobi $Linn\acute{e}$ var. mayuen $S_{TAPF}$. and C. lachryma-jobi $Linn\acute{e}$. In the RAPD analysis with 20 primers, 8 primers gave informative and reproducible bands with the genomic DNA. From the cluster analysis, the genus Coix were divided into two groups at similarity coefficient of 0.863.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.34 no.1
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• pp.74-80
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• 1989

Twentyseven rice cultivars were compared Quantitatively and classified by 15 agronomic traits. For this, 12 Tongil-type rice cultivars and 15 Japonica-type rice cultivars were transplanted at the experimental farm of the Yeongnam Crop Experiment Station on May 25 in 1987. Jangseongbyeo belonging to Tongil-type had the greatest dissimilarity total among 27 rice cultivars and followed by Chilseongbyeo, Gayabyeo, Hangangchalbyeo, Gihobyeo (Tongil-type) and Sangpoongbyeo (Japonica-type) while cultivars having greatest similarity total were Daecheongbyeo and Yeongsanbyeo and followed by Nagdongbyeo, Sinsunchalbyeo, Gwangmyeongbyeo, Yeongdeogbyeo, Palgongbyeo and Dongjinbyeo that were all belonging to Japonica-type cultivars. CuItivar pairs having the greatest dissimilarity coefficient (50-55％) were combinations of Gayabyeo and Sangpungbyeo, Gihobyeo, or Seonambyeo, combinations of Chilseongbyeo and Jangseongbyeo, Sangpung-byeo, Chucheongbyeo, Gihobyeo or Seonambyeo and combinations of }angseongbyeo and Gwangmyeong-byeo, Sangpungbyeo, Gihobyeo, Daechangbyeo or H waseongbyeo. On the other hand, cultivar pairs having the greatest similarity coefficient (above 85 ％) were combinations of Dongjinbyeo and Sinsunchalbyeo, Daecheongbyeo, Somjinbyeo or Yeongsanbyeo, combination of Sangpungbyeo and Gihobyeo, combinations of Yeongdeogbyeo and Yeongsanbyeo or Palgongbyeo, combination of Gwangmyeongbyeo and Yeongdeogbyeo, Combinations of Nagdongbyeo and Gwangmyeongbyeo, Yeongdeogbyeo, Daecheongbyeo, Hwaseongbyeo or Yeongsanbyeo, combinations of Sinsunchalbyeo and Daecheongbyeo or Yeongsanbyeo, combinations of Somjinbyeo and Daecheongbyeo or Yeongsanbyeo and combination of Daecheongbyeo nd Yeongsanbyeo. Two-dimensional ordination analysis method provided the information on cultivar classification between Japonica-type and Tongil-type cultivars except a few cultivars. Only two cultivars, Joongweonbyeo and Seomjinbyeo were located opposit area that implied Tongil-type cultivar Joongweonbyeo was rather close to Japonica-type while Japonica-type cultivar Seomjinbyeo was rather close to Tongil-type, respectively. Sinsunchalbyeo and Daecheongbyeo, on the other hand, were located on the line between two cultivar groups. The method of two-dimensional ordination analysis concluded as feasible approach to classify cultivars Quantitatively for the practical purpose.