• Title/Summary/Keyword: Expected species number

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Stage Structure and Population Persistence of Cypripedium japonicum Thunb., a Rare and Endangered Plants (희귀 및 멸종위기식물인 광릉요강꽃의 개체군 구조 및 지속성)

  • Lee, Dong-hyoung;Kim, So-dam;Kim, Hwi-min;Moon, Ae-Ra;Kim, Sang-Yong;Park, Byung-Bae;Son, Sung-won
    • Korean Journal of Environment and Ecology
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    • v.35 no.5
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    • pp.548-557
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    • 2021
  • Cypripedium japonicum Thunb. is an endemic plant in East Asia, distributed only in Korea, China, and Japan. At the global level, the IUCN Red List evaluates it as "Endangered Species (EN)," and at the national level in Korea, it is evaluated as "Critically Endangered Species (CR)." In this study, we investigated the characteristics of the age structure and the sustainability of the population based on the data obtained by demographic monitoring conducted for seven years in the natural habitat. C. japonicum habitats were observed in 7 regions of Korea (Pochoen, Gapyeong, Hwacheon, Chuncheon, Yeongdong, Muju, Gwangyang), and 4,356 individuals in 15 subpopulations were identified. The population size and structure differed from region to region, and artificial management had a very important effect on the size and structural change of the population. Population viability analysis (PVA) based on changes in the number of individuals of C. japonicum showed a very diverse tendency by region. And the probability of population extinction in the next 100 years was 0.00% for Pocheon, 10.90% for Gwangyang, 24.05% for Chuncheon, and 79.50% for Hwacheon. Since the above monitored study sites were located within the conservation shelters, which restricted access by humans, unauthorized collection of C. japonicum, the biggest threat to the species, was not reflected in the individual viability. So, the risk of extinction in Korea is expected to be significantly higher than that estimated in this study. Therefore, it is necessary to reflect population information in several regions that may represent various threats to determine the extinction risk of the C. japonicum population objectively. In the future, we should expand the demographic monitoring of the C. japonicum population known in Korea.

Initial Risk Assessment of Acetanilide in OECD High Production Volume Chemical Program

  • Park, Hye-Youn;Park, Yoonho;Sanghwan Song;Kwon, Min-Jeoung;Koo, Hyun-Ju;Jeon, Seong-Hwan;Na, Jin-Gyun;Park, Kwangsik
    • Toxicological Research
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    • v.18 no.1
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    • pp.13-22
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    • 2002
  • In Korea, 2,320 tonnes of acetanilide were mostly wed as intermediates for synthesis in phar-maceuticals or additives in synthesizing hydrogen peroxide, varnishes, polymers and rubber. Only small amount of 120 kg were wed as a stabilizer for hydrogen peroxide solution for hair colouring agents in 1998. Readily available environmental or human exposure data do not exist in Korea at the present time. However, potential human exposures from drinking water, food, ambient water and in work places are expected to be negligible because this chemical is produced in the closed system in only one company in Korea and the processing factory is equipped with local ventilation and air filtering system. Acetanilide could be distributed mainly to water based on EQC model. This substance is readily biodegradable and its bioaccumulation is low. Acute toxicity of acetanilide is low since the L $D_{50}$ of oral exposure in rats is 1,959 mg/kg bw. The chemical is not irritating to skin, but slightly irritating to the eyes of rabbits. horn repeated dose toxicity, the adverse effects in rats were red pulp hyperplasia of spleen, bone marrow hyperplasia of femur and decreased hemoglobin, hematocrit and mean corpuscular hemoglobin concentration. The LOAEL for repeated dose toxicity in rats was 22 mg/kg/day for both sexes. Acetanilide is not considered to be genotoxic. In a reproductive/developmental toxicity study, no treatment-related changes in precoital time and rate of copulation, impregnation, pregnancy were shown in all treated groups. The NOAELs for reproduction and developmental toxicity (off-spring toxicity) are considered to be 200 mg/kg bw/day and 67 mg/kg bw/day, respectively. Ecotoxicity data has been generated in a limited number of aquatic species of algae (72 hr- $E_{b}$ $C_{50}$; 13.5 mg/l), daphnid (48hr-E $C_{50}$ > 100 mg/l) and fish (Oryzias latipes, 96hr-L $C_{50}$; 100 mg/l). Form the acute toxicity values, the predicted no effect concentration (PNEC) of 0.135 mg/1 was derived win an assessment factor of 100. On the basis of these data, acetanilide was suggested as currently of low priority for further post-SIDS work in OECD.in OECD.D.

Effects of Climate-Changes on Patterns of Seasonal Changes in Bird Population in Rice Fields using a Prey-Predator Model (포식자-피식자 모델을 이용하여 기후변화가 논습지를 이용하는 조류 개체군 동태에 미치는 영향 예측)

  • Lee, Who-Seung
    • Korean Journal of Environmental Agriculture
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    • v.32 no.4
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    • pp.294-303
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    • 2013
  • BACKGROUND: It is well known that rice-fields can provide excellent foraging places for birds including seasonal migrants, wintering, and breeding and hence the high biodiversity of rice-fields may be expected. However, how environmental change including climate-changes on life-history and population dynamics in birds on rice-fields has not been fully understood. In order to investigate how climate-change affects population migratory patterns and migration timing, I modeled a population dynamics of birds in rice-fields over a whole year. METHODS AND RESULTS: I applied the Lotka-Volterra equation to model the population dynamics of birds that have been foraging/visiting rice-fields in Korea. The simple model involves the number of interspecific individuals and temperature, and the model parameters are periodic in time as the biological activities related to the migration, wintering and reproduction are seasonal. As results, firstly there was a positive relationship between the variation of seasonal population sizes and temperature change. Secondly, the reduced lengths of season were negatively related to the population size. Overall, the effects of the difference of lengths of season on seasonal population dynamics were higher than the effects of seasonal temperature change. CONCLUSION(S): Climate change can alter population dynamics of birds in rice-fields and hence the variation may affect the fitness, such as reproduction, survival and migration. The unstable balances of population dynamics in birds using paddy rice field as affected by climate change can reduce the population growth and species diversity in rice fields. The results suggest that the agricultural production is partly affected by the unstable balance of population in birds using rice-fields.

Metagenomic Analysis of Bacterial Communities in Rhododendron mucronulatum in Biseul Mountain County Park, Daegu, Korea (비슬산 군립공원의 진달래에 대한 박테리아 군집 metagenomics 분석 규명)

  • Choi, Doo-Ho;Jeong, Min-Ji;Kwon, Hae-Jun;Kim, Mi-Gyeong;Kim, Dong-Hyun;Kim, Young-Guk;Kim, Jong-Guk
    • Journal of Life Science
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    • v.30 no.1
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    • pp.32-39
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    • 2020
  • Rhododendron mucronulatum, native to Korea, Mongolia, Russia and parts of northern China, is known not only for its medicinal properties but also as a tourist attraction. One of the most famous tourist destinations with R. mucronulatum is in Biseul Mountain County Park, Daegu, Korea. To investigate the relationship between R. mucronulatum and microbiome communities in the surrounding soil, three sites within the park were chosen for sampling in February and August. The soil samples were then passed through a pyrosequencing process for analysis of the bacterial communities, and a total of 404,899 sequencing reads were obtained. Between 2,349 and 4,736 operational taxonomic units (OTUs) were observed across the three sampling zones and two seasons; samples from the park entrance showed a higher number of OTUs than the other two sites, and samples from August had more OTUs than those from February. The sample from the second observation site displayed the fewest OTUs, particularly in February. According to Chao1 and Shannon indices, samples from the park entrance in August demonstrated the highest degree of species richness and diversity. Studying the bacterial communities across the six samples identified the common population as comprising 287 genera, 45 of which are only present in Biseul Mountain County Park and are expected to participate in the colonization of R. mucronulatum.

A Study for Natural Conservation Value Assessment of Developing Area - Case Study of Alpensia Resort - (개발 예정지역에서의 자연보전 가치 평가 - 대관령 알펜시아 리조트 조성 예정지역을 사례로 -)

  • Choi Hee-Sun;Cho Dong-Gil;Park Mi-Young;Kim Nam-Gyun;Kim Kwi-Gon
    • Journal of the Korean Institute of Landscape Architecture
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    • v.33 no.4 s.111
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    • pp.108-118
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    • 2005
  • While the recent lift of restrictions in greenbelt areas is expected to generate a number of development plans, there are efforts to create various development plans into spatial plans that consider the natural and ecological conditions of development sites. However, these development plans consider Degree of Green Naturality or Degree of Ecology only when designating areas for conservation within development sites. It is true that they don't fully reflect the value of green areas and wetlands as habitats and natural resources. Therefore, this study built an conservation value assessment model that is applicable to sites where development is planned in Korea by reviewing prior case examples md studies and applied the developed model to a case study area. The site where the conservation value assessment model was applied to is an area around Yongsan-ri and Suha-ri, Doam-myon, Pyeongchang-gun, Gangwon province where quality natural resources are located in and wend the site. This is a site for the development of Alpensia Resort where a resort including facilities for the Winter Olympics is planned to be introduced. In order to assess the conservation value of the site for Alpensia Resort, a total of eight items including area, distribution of communities, habitation of species with conservation value, functions of habitats, connectivity of habitats, vegetation layers of forests, age of forests, and ratio of non-native plants were studied through literature review and field surveys. The assessment was made by dividing the site into 95 habitats that are perceived by aerial photographs and each habitat unit was assessed on the eight items in a 3-point scale. Each unit habitat assessed in a 3-point scale was segmented into primary, secondary or tertiary areas based on the conservation value. Habitats assessed as primary were designated as priority (absolute) conservation areas and those assessed as secondary and tertiary were set as secondary conservation areas and tertiary conservation areas, respectively. As a result, each area represented 26.9%, 20% and 3% of total site area. Based on this result, habitat management plans were developed to conserve primary conservation areas, improve secondary conservation areas and restore tertiary conservation areas. In addition, a development plan was developed to create habitats in areas where new habitats are requested in order to build an eco-network in the site and a plan to create eco-corridors was proposed. In developing a land use plan for the site, a development plan that considers conservation areas first should be set up based on the outcome of conservation value assessment. This can be linked to the development of an environment-friendly land use plan as well as easing the establishment of a green area and eco-network. This study will facilitate the implementation of the 'conservation before development' principle, which can prevent reckless development, by assessing conservation value in setting up development plans.

Characteristics of Planting Design according to Parking Lots Type in Multi-family Housing Complex (공동주택단지의 주차장 유형에 따른 식재특성)

  • Hong, Seong-Rae;Jeong, Dae-Young;Shim, Sang-Ryul
    • Journal of the Korean Institute of Landscape Architecture
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    • v.37 no.1
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    • pp.43-49
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    • 2009
  • The number of registered vehicles increased to one million in 1985 and ten million in 1997, and the parking lots in multi-family housing complex that had been mainly constructed on the ground level began to be constructed in underground levels. Therefore, planting design in such complex were greatly changed. This study classifies the parking lots in multi-family housing complexes located in Cheongju into three categories: above-ground, mixture of above-ground and underground, and underground. The characteristics of planting design in each were then analyzed. The rate of parking per family increased by two or more in the type of mixture when compared to in the type of above-ground. As underground parking lots became dominant, the rate of parking per family increased to one car or more. The green area ratio did not change considerably when above-ground parking was combined with underground parking, but the green area per total floor space was reduced, which indicates the quality of green area became lower. Most of the parking lots in multi-family housing complexes since 2000 have been constructed underground, and the green area became larger. As for the species of trees used in planting design, trees that are vulnerable to damage by blight and harmful insects and may be repugnant have been reduced and replaced by trees whose shapes are beautiful and whose flowers and fruits can be appreciated, such as Chionanthus retusa, Malus floribunda, Styrax japonicus, Prunus mume, Lagerstroemia indica. Pine trees are variously planted with diversified standards, and, in particular, tall pine trees are being utilized as focal points. Herbaceous flowers began to be planted in underground parking lots constructed since 2000, and they are expected to be planted even more due to the appreciation of their flowers and their splendid appearance.

Genetic Polymorphism of Microsatellite Markers in Panax ginseng C.A. Meyer (인삼 (Panax ginseng C.A. Meyer)의 Microsatellite 마커에 대한 유전적 다형성과 특성 규명)

  • Park, Sun-Wha;Hyun, Young-Se;Chung, Ki-Wha
    • Journal of Ginseng Research
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    • v.33 no.3
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    • pp.199-205
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    • 2009
  • Ginseng (Panax ginseng C.A. Meyer) is one of the most important medicinal plants in East Asia. Microsatellite or simple sequence repeat (SSR) markers are used in obtaining genetic analysis and authentication in many plants. The present study examined five microsatellites in conjunction with P. ginseng in Korea. The total observed allelic number was 17 (mean = 3.4), and gene diversities varied from 0.078 to 0.543 with an average of 0.314. Through a combined analysis of five loci in 100 ginseng samples, 44 different combined genotypes were observed. Expected and observed heterozygosites ranged from 0.077 to 0.541 (mean = 0.313) and 0.040 to 0.130 (0.083), respectively. All examined loci exhibited deficiency of heterozygosity and deviation from the Hardy-Weinberg equilibrium. Such results may be explained by the non-random mating and inbreeding that has occurred for several hundred years. These microsatellite markers could be used for the study of molecular genetics and the establishment of DNA marker database, as well as authentication of ginseng species and chromosomal mapping of QTL loci in P. ginseng.

Variation in Catch Size and Changes in Reproductive Biology of Common Octopus Octopus vulgaris in the Coastal Waters Off Gyeongnam, Korea (경남 지역에서 서식하는 참문어(Octopus vulgaris)의 자원 변동과 생식 생태의 변화)

  • Song, Se Hyun;Park, Jong Hyeok;Ji, Hwang-Sung;Choi, Jung Hwa;Kim, Hee Jun;Jeong, Jae Mook;Kim, Do Hoon
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.53 no.1
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    • pp.57-66
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    • 2020
  • The purpose of this study was to provide information about annual variations in catch size and changes in reproductive biology in the common octopus Octopus vulgaris, a commercially important species. Samples were collected from coastal waters off Gyeongnam, Korea, by coastal trap and coastal complex fishery from February to December 2018. Octopus vulgaris have been decreasing in this region since 2007 and catch prices have been increasing. The mantle length (ML) of O. vulgaris ranged from 1.2 to 21.2 cm and body weight ranged from 42.6 to 5,537 g. The sex ratio differed significantly from what was expected, at 0.45:0.55 (P<0.05). Mature females were found from February to December, except in October and November, and males occurred from February to December, except in October. The gonadosomatic index value was higher from May to September than in other months. The total number of eggs in fecund individuals ranged from 40,280 in 578.1 g of body weight to 138,994 in 1,666.5 g of body weight. The relationship between body weight and fecundity was F=76.486BW1.0087 (r2=0.7897). At 50% group maturity, average weight was estimated to be 636.35 g, while it was 969.30 g at 75% maturity and 1736.55 g at 97.5% maturity. This study highlights changes in catch size and reproductive biology between 2007 and 2018. These results provide basic evidence that may be used to establish regulatory policy for O. vulgaris fisheries.

Dynamics of Total Phosphorus and Attached Bacteria in a Porous Medium Concentrating Nutrients from Low-Nutrient Water (저농도 영양염류를 농축하는 여재에서 총인과 부착세균의 변화)

  • Kim, Ju-Young;Nam, Jong-Hyun;Jung, Da-Woon;Cho, Ahn-Na;Choi, Seung-Ik;Ahn, Tae-Seok
    • Korean Journal of Microbiology
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    • v.45 no.2
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    • pp.133-139
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    • 2009
  • A nutrient-concentrating system was operated to retrieve total phosphorus efficiently from a non-point pollution source. Attached bacteria were expected to play an important role in the system. Phosphorous was concentrated by formation of bacterial biofilms on rubberized coconut fiber media of the system. While concentration of total phosphorus (TP) ranged merely 0.12~0.35 mg/L in the stream water, TP levels in pore water and the media were 0.45~0.86 mg/L and 40.91~242.71 mg/kg, respectively. Total bacterial number (TBN) ranged $0.3\sim2.3\times10^6$ cells/ml in stream water, $0.4\sim4.4\times10^6$ cells/ml in pore water and $0.8\sim1.9\times10^9$ cells/g in media. There was a close correlation between TP and TBN. Based on band profiles in DGGE analyses, bacterial communities in the media were different from that in the stream water. Clostridium spp. were abundant in the stream water while Aquabacterium spp. were dominant species in early stages of biofilm formation in the media. The genera predominant in matured biofilms of the media were Clostridium and Enterococcus.

An Overview for Molecular Markers in Plants (식물에서 분자 마커의 동향)

  • Huh, Man Kyu
    • Journal of Life Science
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    • v.25 no.7
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    • pp.839-848
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    • 2015
  • A molecular marker is a molecule contained within a sample taken from an organism or other matter. The development of molecular techniques for genetic analysis has led to a great contribution to our knowledge of plant genetics and our understanding of the structure and behavior of various genomes in plants. Recently, functional molecular markers have been developed to detect the presence of major genes from the analysis of pedigreed data in absence of molecular information. DNA markers have developed into many systems based on different polymorphism-detecting techniques or methods such as RFLP, AFLP, RAPD, SSR, SNP, etc. A new class of very useful DNA markers called genic molecular markers utilizing the ever-increasing archives of gene sequence information being accumulated under the EST sequencing projects on a large number of plant species. Functional markers are derived from polymorphic sequences, and are more likely to be involved in phenotypic trait variation. Based on this conceptual framework, the marker systems discussed below are all (gene)-targeted markers, which have the potential to become functional. These markers being part of the cDNA/EST-sequences, are expected to represent the functional component of the genome i.e., gene(s), in contrast to all other random DNA based markers that are developed/generated from the anonymous genomic DNA sequences/domains irrespective of their genic content/information. Especially I sited Poczai et al’ reviews, advances in plant gene-targeted and functional markers. Their reviews may be some useful information to study molecular markers in plants.