• Title/Summary/Keyword: 개체군 연구

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Temporal variation of wintering bird population and environmental factors in Donglim reservoir (동림저수지에서 월동조류 개체군의 시계열적 변화와 환경 요인)

  • Park, Jongchul;Kim, Woo-Yuel
    • Journal of Wetlands Research
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    • v.19 no.2
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    • pp.223-229
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    • 2017
  • This study analyzed the relationship between environmental factors and the temporal changes of the bird populations during the every January from 1999 to 2016 (18 years) in Donglim reservoir. 'Winter Waterbird Census of Korea' data by National Institute of Biological Resources were used for the bird population data, and principal component analysis and cluster analysis were used to analyze the changes of annual population. The average temperature of January and the average storage rate of the reservoir were used as environmental factors. According to the results of the study, the population changes in the study area can be explained by the increase and decrease of two water bird groups and a mountain bird group. The average temperature of the years when the population of water bird groups increased was more than $1.4^{\circ}C$ in comparison with the year when mountain birds increased. On the other hand, the influence of the water content was not clear. The visiting of Baikal Teal affected by temperature was a factor affecting the other group of water bird and a mountain bird group. The results of this study suggest that the temperature change affects the global spatial distribution of birds and the migration of large population species such as Baikal Teal affects species composition and populations of birds at local scale. Therefore, understanding of environmental changes at large scale and spatial distribution of species and flock contributes to understand the temporal variation of the bird population at regional or local scales.

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.

Fish fauna and characteristics of Misgurnus anguillicaudatus and Aphyocypris chinensis populations in environmentally friendly and conventional paddy fields (관행 논과 친환경 논의 어류상 및 미꾸리와 왜몰개 개체군 특성)

  • Jeong Hwan Bang;Min-Kyeong Kim;Soon-Kun Choi;Jinu Eo;So-Jin Yeob;Myung-Hyun Kim
    • Korean Journal of Environmental Biology
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    • v.40 no.2
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    • pp.138-147
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    • 2022
  • Paddy fields are important habitats for maintaining the biodiversity of agricultural ecosystems. Recently, as the need for safe food and biodiversity conservation has increased, the rice cultivation methods have undergone changes. This study was conducted to investigate the fish fauna in Environmentally Friendly Paddy fields (EFP) and Conventional Paddy fields (CP), and compare the characteristics of Misgurnus anguillicaudatus and Aphyocypris chinensis populations in EFP and CP. A total of 2,703 fish were collected and classified into six families and 13 species. Our results showed that there was a difference in the proportion of fish populations in the two paddy fields, and the number of individuals in EFP was higher than in CP. The weight values of M. anguillicaudatus were higher in EFP than in CP, and the total length, body length, and weight values of A. chinensis were higher in EFP than in CP. Conditional factor(K) values also showed similar trends in EFP and CP. Our results indicate that the farming practices in paddy fields have a significant effect on the characteristics of M. anguillicaudatus and A. chinensis populations, and the results of this study can be used as basic data for securing biodiversity in future agricultural ecosystems.

Effects of air current speed on the growth of plug seedlings under artificial light (기류속도가 인공광하의 플러그묘 생장에 미치는 영향)

  • 김용현
    • Proceedings of the Korean Society for Bio-Environment Control Conference
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    • 1997.05a
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    • pp.74-79
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    • 1997
  • 플러그묘의 생육과 밀접한 관계를 갖는 플러그묘 개체군(이하 '묘개체군' 이라 칭함) 내외에서의 미기상 요소는 기류속도의 영향을 크게 받는다. 인공광을 이용한 반폐쇄생태계에서 품질이 균일한 플러그묘 생산 시스템 개발을 목적으로 실험을 수행한 금과 고재$^{(1)~(4)}$ , Kim등$^{(5)}$ 은 최근들어 플러그묘 생산용 풍동 설계 및 공기역학적 특성의 구명, 기류속도가 묘개체군내외에서 기온ㆍ상대습도ㆍ포차ㆍ$CO_2$ 농도의 분포에 미치는 영향, 묘개체군의 순광합성 속도 측정 등에 관한 연구 결과를 보고한 바 있다. (중략)

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ITS Sequence Variations in Populations of Ilex cornuta (Aquifoliaceae) (호랑가시나무(Ilex cornuta) 개체군의 ITS 염기서열 변이 분석)

  • Son, Sung-won;Kim, Joo-Hwan;Kim, Yong-Shik;Park, Seon-Joo
    • Korean Journal of Plant Taxonomy
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    • v.37 no.2
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    • pp.131-141
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    • 2007
  • Genetic variation of Ilex cornuta Lindley et Paxton was examined by sequence analyses of ITS for 65 individuals from Korea and China. The length of ITS 1 ranged from 253 to 259 bp. The 5.8S was 159 bp and ITS2 was observed to be 231 bp. A total of 8 different ITS types (Single Nucleotide Polymorphism haplotypes), which showed the difference of 1 - 6 bp, were detected from 65 individuals. The sequence polymorphisms of ITS appeared at 9 different sites. All of four individuals collected at Daejeong-eup in Jeju-do exhibited different types, but all individuals from Naju-si and Muan-gun in Jeollanam-do were identical. The variation of ITS was higher in Jeju-do population than in inland population. Since I. cornuta contains various types of ITS sequences, ITS analyses will provide important information on genetic diversity and conservation of this species.

Dispersal of potential habitat of non-native species tilapia(Oreochromis spp.) inhabiting rivers in Korea (국내 하천에 서식하는 외래종 틸라피아(tilapia)의 잠재적 서식처 확산)

  • Ju Hyoun Wang;Jung Soo Han;Jun Kil Choi;Hwang Goo Lee
    • Korean Journal of Environmental Biology
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    • v.41 no.2
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    • pp.101-108
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    • 2023
  • Recently, in relation to climate change, many studies have been conducted to predict the potential habitat area and distribution range of tilapia and the suitability of habitat for each species. Most tilapia are tropical fish that cannot survive at water temperatures below 10 to 12℃, although some tilapia can survive at 6 to 8℃. This study predicted habitable areas and the possibility of spreading of habitat ranges of tilapia (Oreochromis niloticus and Oreochromis aureus) known to inhabit domestic streams. Due to climate change, it was found that habitats in the Geum River, Mangyeong River, Dongjin River, Seomjin River, Taehwa River, Hyeongsan River, and the flowing in East Sea were possible by 2050. In addition, it was confirmed that tilapia could inhabit the preferred lentic ecosystem such as Tamjin Lake, Naju Lake, Juam Lake, Sangsa Lake, Jinyang Lake, Junam Reservoir, and Hoedong Reservoir. In particular, in the case of tilapia, which lives in tributaries of the Geumho River, Dalseo Stream, and the Nakdong River, its range of habitat is expected to expand to the middle and lower of the Nakdong River system. Therefore, it is judged that it is necessary to prepare physical and institutional management measures to prevent the spread of the local population where tilapia currently inhabits and to prevent introduction to new habitats.

Genetic Diversity of Rana catesbiana Captured on various sites in Korea based on mitochondrial ND1 sequence (미토콘드리아 ND1 유전자 염기서열 비교를 통한 국내 서식 황소개구리의 유전적 다양성 조사)

  • Lee Ji-Young;Shim Jae-Man;Joung Insil
    • Proceedings of the KAIS Fall Conference
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    • 2005.05a
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    • pp.297-300
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    • 2005
  • 1970년대 식용을 위한 양식을 목적으로 일본에서 수입된 황소개구리가 국내 하천과 호서생태계에 큰 피해를 주었으나, 최근 급속히 그 개체수가 줄어든 것으로 추정되므로 이번 연구에서는 국내에 서식하는 북미산 황소개구리의 유전자 분석을 통하여 개체동태군에 대한 유전적 연관을 조사하였다. 이를 위하여 전라남도 지역에서 서식하는 황소개구리를 채집하여 이미 발표된 북미산 황소개구리와 미토콘드리아 ND1/tRNA 유전자 1215bp의 염기서열을 비교, 분석하였다. 북미산과 비교하였을 때 조사한 국내 서식 개체 모두에게 ND1/tRNA 유전자 1개 위치에서 염기변화가 발견되었으나 이는 도입 개체군의 유전자인지 국내 특이변이가 진행된 것인지 확실하지 않다. 또한 조사한 개체 일부에서 유전자 염기서열의 6위치에서의 변이가 발견되었으나 국내 서식 황소개구리는 미국산 황소개구리와의 유전적 차이가 거의 없으며, Kimura-2-parameter 분석결과 국내 서식 황소개구리 개체 내에서 $98.7\%\~100\%$의 높은 유사성을 보여 종내 유전적 차이가 거의 없는 것으로 보인다. Neighbor-Joining과 Maximum Parsimony 분석 결과, cluster를 이루는 개체군의 차이를 보였으므로 개체들이 분화되어 나온 시점과 위치가 다른 것으로 확인되었지만 장흥, 영암, 고흥의 개체가 국내 도입시기의 개체군에 속하며 광주, 남평 지역의 개체군이 고흥의 한 개체로부터 분화되어 나왔음을 추정할 수 있다. 이러한 결과로부터 국내에 서식하는 황소개구리가 도입 후 지역 특이적 분화가 일어났다고 결정하기는 무리가 있으며, 이와 같이 유전적 유전도가 높은 개체들간의 교배에 따른 유전적유전적 다양성의 감소가 최근에 관찰되는 국내산 황소개구리의 급격한 감소원인들 중의 하나일 가능성을 시사한다.년도) 18,756, 2045(년도) 22,595, 시장점유율 증가로 인한 수출액 증가분 누적(억원) : 2015(년도) 3,411, 2025(년도) 8,847, 2035(년도) 14,433, 2045(년도) 18,005 또한 시나리오 비교평가를 실시하여 본 결과, 본 연구에서 정의한 순편익 누적(Cumulative Net Profit) 변수를 적용하면 현재 연구비 추세 대비 $30\%$ 까지 연구비를 증가 시키는 것이 효율적임을 알 수 있었다.성, 생산 용이성, 제품 디자인의 우수한 정도가 a=0.01 수준 하에서 유의적으로 추정되었다. 이들 변수들 중에서 품질경쟁력에 가장 큰 영향을 미치는 측정변수는 제품의 기본 성능, 수명(내구성), 신뢰성, 제품 디자인의 순서로 추정되었다. 이것은 한국 제조업이 아직 산업 디자인이 품질경쟁력에 크게 영향을 미치는 성숙단계에 이르지 못하였음을 의미한다. (2) 제품 디자인에게 영향을 끼치는 유의적인 변수는 연구개발력, 연구개발투자 수준, 혁신활동 수준(5S, TPM, 6Sigma 운동, QC 등)이며, 제품 디자인은 우선 품질경쟁력을 높여 간접적으로 고객만족과 고객 충성을 유발하는 것으로 추정되었다. 상기의 분석결과로부터, 본 연구는 다음과 같은 정책적 함의를 도출하였다. 첫째, 신상품 개발과 혁신을 위한 포괄적인 연구개발 프로젝트를 품질 경쟁력의 주요 결정요인(제품의 기본성능, 신뢰성, 수명(내구성) 및 제품 디자인)과 연계하여 추진해야 할 것이다. 둘째, 기업은 디자인 경영 마인드 제고와 디자인 전문인력 양성을, 대학은 디자인 현장 업무를 통하여 창의력 증진과 기획 및 마케팅 능력 교육을, 정부는 디자인 기술개발 및 디자인 교육지원의 강화를 통하여 각각 디자인 경쟁력$\rightarrow$품질경쟁력을 제고시켜야 할 것이

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The Study on the Height Characteristics of Abies Nephrolepis Community in South Korea - In the Case of Seorak·Odae·Taebaek National Park - (우리나라 분비나무의 수고 특성 연구 - 설악·오대·태백산국립공원을 대상으로 -)

  • Jin-Won Kim;Ho-Young Lee;Young-Moon Chun;Choong-Hyeon Oh
    • Korean Journal of Environment and Ecology
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    • v.38 no.2
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    • pp.169-177
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    • 2024
  • This study investigated whether population dynamic analysis based on the height characteristics of Abies nephrolepis was feasible. It was necessary because existing population dynamic analyses based on age and diameter at breast height (DBH) made it difficult to reflect the slow growth characteristics of Abies nephrolepis in harsh environments of high altitudes. The limitations of population dynamics analysis based on the age and DBH distribution of Abies nephrolepis in Seoraksan, Odaesan, and Taebaeksan National Parks, where Abies nephrolepis populations are representative, were verified, and the characteristics of height growth were investigated to comprehensively analyze whether a vertical structure based on height could reveal the population dynamics. The result of this study showed some limitations in understanding the population dynamics of Abies nephrolepis based on age distribution due to practical difficulties in sampling all trees and variations in age distribution within the same community depending on factors such as light conditions. Moreover, it was challenging to differentiate the distribution of DBH classes at fine levels, making it difficult to reflect the rapid growth characteristics of Abies nephrolepis when light conditions become suitable after prolonged stays in smaller DBH classes under shade conditions. However, a comprehensive analysis of the height characteristics of Abies nephrolepis revealed that the density corresponding to the population dynamic characteristics of Abies was high and adequately reflected the predominant tree death at similar height stages, as well as the U-shaped population dynamics at the lower stratum. Moreover, it was possible to identify a transition point in height values under shaded conditions, where the annual growth of Abies nephrolepis individuals in the lower stratum increases significantly, indicating that Abies nephrolepis individuals can escape from competition with other shrubs and undergo vigorous growth only at this height level. Therefore, this study confirmed that a vertical structure based on height can be utilized to understand the population dynamics of Abies nephrolepis in high altitudes, and it is expected that future studies on height characteristics can intuitively reveal the maintenance status of Abies nephrolepis populations in the field.

Studies on the Dry Matter Production and Structure of Rice Plants I. Growth Rate and Productive Structure of Rice Population (수도(水稻)의 물질생산(物質生産)과 그 구조(構造)에 관(關)한 연구(硏究) I. 수도개체군(水稻個體群)의 생장속도(生長速度)와 생산구조(生産構造))

  • Ahn, Su Bong
    • Korean Journal of Agricultural Science
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    • v.8 no.1
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    • pp.3-10
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    • 1981
  • In order to analyze growth and yield of rice population at the stand point of productive ecology, productive structure and growth rate of rice plants and effects of their related factors were studied. The results obtained were summarized as follows: 1. High crop growth rate was maintained throughout growing season when rice plants grew in population compared to a single rice plant. Since crop growth rate in rice stands were also higher at ripening stage, higher yields were obtained. 2. Higher crop growth rate of rice plants in population was maintained by the increase of leaf area rather than by net assimilation rate. 3. As the overgrowth of upper leaves of plant population in some rice varieties transmission of light into lower leaves was inhibited and thus most of them were eventually died before flowering. 4. In the case of rice population, the ratio of productive organ to non-productive organ, light transmission rate and nitrogen contents of active leaf blade were lower than individual rice plants under isolated condition.

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Distribution Characteristics, Population Structure and Dynamics of the Endangered Plant, Viola websteri Hemsl. (멸종위기야생식물인 왕제비꽃(Viola websteri Hemsl.)의 분포특성과 개체군 구조 및 동태)

  • Chae, Hyun-Hee;Kim, Young-Chul;Kwak, Myoung-Hai;Nam, Gi-Heum
    • Korean Journal of Environment and Ecology
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    • v.35 no.1
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    • pp.48-67
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    • 2021
  • Plant species exhibit current characteristics as a result of interactions with environmental conditions. The plants of Viola sp. have selected chasmogamous flowers with vigorous vegetative propagation or development of cleistogamous flowers as an adaptation strategy. Viola websteri is distributed on the Korean peninsula and the eastern part of Jilin Province, China. The center and edge of the distribution are expected to exhibit different population-dynamics. It is necessary to investigate the cause of its current limited distribution even though V. websteri has a mixed-mating strategy. Firstly, We examined the vegetation environment of habitats and evaluated its characteristics. Growth characteristics were examined through plant phenology. We then evaluated the population structure, characteristics of chasmogamous flowers, and productivity of cleistogamous flowers. Moreover, we compared population sizes between 2014 and 2018. Most habitats were located in deciduous broadleaf mixed forests adjacent to valleys. V. websteri produced chasmogamous flowers with self-incompatibility in April-May and cleistogamous flowers in June-September. The cleistogamous flower production is a strategy ensuring seed production under uncertain environmental fluctuations; these were approximately twice as numerous as chasmogamous flowers. The population structure was distinguished into stable and very unstable regions. There were sites where the population experienced a sharp decline in the 2018 compared to that of 2014. This large decline was found in the edge populations. The habitats had different microsites depending on the natural disturbances of drought and the matrix constituting the habitat, thus supporting various plants. Ensuring the production of seeds through cleistogamous flowers, it was determined that rapid seedling re-establishment and population replenishment were possible when the natural disturbance factor was removed. Environmental factors did not equally affect all populations or individuals. Therefore, it was expected that it would be able to persisted in a long time, despite the rapid decrease in the number of individuals in the population regionally. Local extinction and re-establishment are likely to repeat according to environmental change. We propose the additional population investigation based on this works are required. We also suggest a need to assess the long-term population dynamics and the genetic characteristics of chasmogamous flowers and cleistogamous flowers to establish and implement effective conservation strategies.