• 제목/요약/키워드: Age Structure of Population

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대전광역시 노령화 지구의 공간적 분포 패턴 (Spatial Distribution of Aging District in Taejeon Metropolitan City)

  • 정환영;고상임
    • 한국지역지리학회지
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    • 제6권2호
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    • pp.1-19
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    • 2000
  • 본 연구는 중부지역의 중심지로 발전하고 있는 대전광역시를 대상으로 노령화 지구의 공간적 분포 패턴을 분석하고자 하였다. 그 결과 노령화 지구는 대전광역시 CBD지역과 CBD인접지역, 그리고 주변지역간에 뚜렷한 차이를 나타내고 있으며, 그 분포에 있어서도 양극화 현상이 뚜렷함을 확인하였다. 그리고 인구감소지구는 노령화지구와 대체로 중복되어 있고, 비노령인구의 전출에 의하여 노령인구비율이 높아지고 있으며, 인구증가지구는 노령화 지구와 전혀 중복되어 나타나지 않고, 비노령인구의 전입에 의해 노령인구비율이 낮아지고 있다. 인구이동에 의한 노령인구의 증가여부를 확인하기 위하여 각 그룹별로 연령 코호트 분석방법을 이용하여 노령화 지구의 출현요인을 분석한 결과, 인구노령화의 진행 은 인구의 사회적 증감률 변화와 매우 밀접하게 관련되어 있고, 특히 비노령인구의 전출에 의해 노령인구비율이 높아지고 있음을 확인할 수 있었다. CBD지역과 CBD인접지역을 포함한 중심시가지에서는 결혼, 새로운 주택취득에 의한 세대분리 등의 전출, 즉, 비노령인구의 전출이 인구노령화를 촉진하는 주요인이 되고 있고, 반면 주변지역에서는 비노령인구의 지구의로의 전출뿐 아니라 새롭게 노령인구로 편입되어져 가는 연령층 인구와 사망률의 저하에 따른 평균수명의 연장으로 인한 노령인구의 절대적 증대가 인구노령화를 촉진하는 요인으로 작용하고 있다.

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Rederivation of Gertler's model and analysis of the Korean economy

  • Lee, Hangsuck;Son, Jihoon
    • Communications for Statistical Applications and Methods
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    • 제27권6호
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    • pp.649-673
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    • 2020
  • This paper makes a theoretical contribution by providing clear and detailed derivation of economic agents' decision problems including elastic labor supply in Gertler's overlapping generation (OLG) model. We apply the model to the Korean economy by calibration based on Korean economic data. It also analyzes the impact of current social issues such as aging and extension of retirement age, on the Korean economy in a long-run equilibrium. Subsequently, we also discuss the implications of the analysis. Aging has prolonged the period of retirement; therefore, population structure changes by the increase in the proportion of retirees, the total consumption-to-GDP ratio decreases, and capital stock increases due to reduced propensity to consume out of wealth in preparation for an individual's retirement life. The implementation of retirement age extension increases the proportion of retirees relatively less and alleviates fluctuations in labor supply and the share of financial assets for both economic agents. However, the decrements in consumption-to-GDP ratio is larger than before, and this leads to a larger rise in the capital stock compared to when there is only an aging effect.

年齡別 人口構成에서 본 淸州市의 居住패턴 變化 (Changes in residential patterns by the age composition in Cheongju city, Korea)

  • 한주성
    • 대한지리학회지
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    • 제30권1호
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    • pp.57-67
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    • 1995
  • 1970-1990년 사이 연령별 인구구성비에 의한 청주시의 동 유형의 변화를 분석한 결과 다음과 같은 점이 밝혀졌다. \circled1 연령별 인구구성비에 의한 유형의 공간적 분포는, 1970 년에는 도심과 그 인접지역이 동심원패턴을, 주변지역은 선형패턴을 나타내었으나, 1980년에 는 도심의 인접지역과 주변지역이 선형패턴을 나타내었다. 1990년에는 도심과 그 인접지역 이 원형으로, 주변지역은 세분된 선형패턴으로 나타났다. \circled2 연령별 인구구성비에 의한 유형 의 변화는 1970년대에는 미학령 연령층과 35-49세의 장년충 인구구성비가, 1980년대에는 유.소년층과 40-49세, 55-64세의 장년층, 70-79세, 85세 이상 노년층의 연령구성비가 유형 의 공간적 변화를 가져왔다고 할 수 있다. 이와 같은 변화가 주로 나타난 지역은 도심과 주 변지역이다. \circled3 연령별 인구구성비에 의한 유형의 변화가 나타난 원인은 제조업의 발달로 인구가 증가함에 따라 도심의 인접지역이나 주변지역에 신흥 단독주택과 아파트가 많이 건 설되어 이들 지역에 청년층의 인구가 전입하여 본래 거주하고 있던 노년층과 혼재되었기 때 문이다.

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금개구리 (Rana chosenica) 개체군의 생존분석: 개체군의 효과적인 보존과 야생복귀를 위한 제안 (Population Viability Analysis of a Gold-spotted Pond Frog (Rana chosenica) Population: Implications for Effective Conservation and Re-introduction)

  • 정석환;성하철;박대식;박시룡
    • 환경생물
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    • 제27권1호
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    • pp.73-81
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    • 2009
  • 멸종위기종 금개구리 (Rana chosenica)개체군의 존속 가능성을 알아보고 효과적인 보전 대책의 마련과 야생복귀 방법을 개발하기 위하여 충북 청원군에 서식하는 개체군을 대상으로 개체군생존분석을 실시하였다. 해당 금개구리의 개체군은 30년간 1,000회의 시뮬레이션을 통해 0.113의 낮은 성장률을 가지고 존속해 나갈 것이라 예측이 되었으나 절멸가능성 또한 81.1%로 매우 높아 환경적으로 민감한 특징을 가지고 있었다. 금개구리 개체군의 개체군 성장률과 절멸가능성은 변태율의 변화에 대해 가장 민감하게 반응하는 것으로 나타났는데, 이는 금개구리의 야외 개체군을 안정적으로 유지하기 위해서는 무엇보다도 금개구리 유생이 변태할 때까지의 생존율을 높이는 것이 결정적이라는 것을 의미한다. 항아리곰팡이병이나 개구리바이러스와 같은 질병이 발병할 경우 개체군의 절멸확률이 100%로 예측되었다. 절멸 개체군의 야생개체군 복원의 방법으로는 수컷의 비율을 83%, 투여개체들의 나이구조가 정상분포를 보이는 100마리의 개체군을 200마리를 수용할 수 있는 지역에 복귀를 시키고, 4년 후 2년 단위로 10년 후까지 10%씩 보충하는 방법이 가장 안정된 개체군을 복원, 유지하는 방법으로 나타났으며, 이 복원된 개체군의 경우 지속적으로 금개구리의 유생이 변태할 때까지의 생존율을 높일 수 있는 보호대책이 마련된다면 성장률 0.297, 절멸가능성 0.290을 갖는 안정된 개체군을 30년 후 138마리까지 유지할 수 있을 것으로 분석되었다. 이러한 결과들은 금개구리 개체군의 보전과 재도입을 위한 효과적인 전략수립의 근거로 활용될 수 있을 것이다.

농민이촌(農民離村)과 농업인구(農業人口)의 변화(變化) (Rural Migration and Changes of Agricultural Population)

  • 오총현;김경호
    • 농업과학연구
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    • 제1권1호
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    • pp.91-116
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    • 1974
  • 최근(最近) 십여년간(十餘年間) 대만(台灣)의 상공업(商工業)은 급속(急速)한 성장(成長)을 이룩하여 오면서 농공상간(農工商間)의 소득(所得)의 격차가 날로 커져만 왔다. 이러한 경제수입(經濟收入)의 격차는 농민사회(農民社會)에 심리적(心理的)인 불안(不安)한 요소(要素)로 등장(登場)하면서 부터 결과적(結果的)으로는 농민이촌(農民離村)에 따른 전업(轉業)의 현상(現象)을 낳게 한 것이다. 통계(統計)에 의(依)하면 1960년지(年至) 1969년간(年間) 대만(台灣)의 십대도시(十大都市)에 있어서의 인구(人口)의 평균증가율(平均增加率)을 보면 4.05%로 나타났으며 기여지역(其餘地域)은 2.06%로 나타나 있는 것이다. 만약(萬若)에 도시(都市)와 농촌(農村)과의 인구자연증가율(人口自然增加率)이 양자균등(兩者均等)하다고 가정(假定)할 경우(境遇) 위에 언급(言及)한 도시인구(都市人口)의 증가현상(增加現象)은 마땅히 농촌인구(農村人口)가 도시(都市)로 유입(流入) 되었다고 보아야 할 것이다. 오늘날 농업인구(農業人口)의 대량외류(大量外流)는 사회경제문제(社會經濟問題)를 보다 복잡(複雜)하고 광범(廣汎)하게 하였으며 이러한 현상(現象)은 결국(結局) 농촌(農村)의 젊은 청년층(靑年層)의 생산자(生産者)가 외류(外流)의 주종(主宗)을 이뤄 자연(自然) 농업생산력(農業生産力)을 저하(低下)시키는 현상(現象)을 초래(超來)케 되었다. 동시(同時)에 도시(都市)에는 주거(住居), 교통(交通), 질서문제등(秩序問題等)이 사회문제(社會問題)로 대두되게 된 것이다. 반면(反面) 농업인구(農業人口)의 외류(外流)는 그 구조(構造)가 비대(肥大)해 가고 있는 상공업(商工業) 분야(分野)에 보다 많은 노동력(勞動力)을 제공(提供)할 수 있으며 농업인구(農業人口)의 상대적(相對的)인 감소(減少)로 하여금 농장경영규모(農場經營規模)를 확대(擴大)시킬 수 있는 하나의 기회(機會)로 잡아 봄직도 한 것이다. 본문(本文)은 농업인구(農業人口)의 유출량(流出量)은 농업발전(農業發展) 및 농촌지도사업(農村指導事業)과는 상호(相互) 어떤 관계(關係)가 있나에 분석(分析)의 중점(重点)을 두었으며 구체적(具體的) 연구(硏究) 목적(目的)으로는; 1. 도시(都市)와 농촌인구구조(農村人口構造)의 비교(比較) 2. 농업인구(農業人口)의 변화(變化) 및 추계(推計) 3. 농업발전(農業發展) 및 농촌지도(農村指導)에 대(對)한 영향(影響)이며 결론(結論) 및 건의사항(建議事項)으로 1. 이촌농가(離村農家)에 대(對)한 지도책등(指導策等)을 마련하여 그들로 하여금 그들의 토지(土地)를 전업농(專業農)에게 양도(讓度)토록 유도(誘導)한다. 2. 경영규모(經營規模)의 확대(擴大)를 원(願)하는 농가(農家)에 대(對)한 정부(政府)의 자금지원(資金支援). 3. 농촌지도사업내(農村指導事業內)에 이촌전업자(離村轉業者)를 위(爲)한 비농업직업훈련과정(非農業職業訓練課程)의 증설(增設). 4. 평형적(平衡的)인 농촌인력자원(農村人力資源)의 확보(確保) 및 이의 유효적절(有效適切)한 운용(運用)으로 농업(農業) 및 농촌발전(農村發展)을 촉진(促進)시키기 위(爲)한 적량농촌인구정책(適量農村人口政策)의 입안(立案)(optimum population policy).

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Mitochondrial Cytochrome b Sequence Variations and Population Structure of Siberian Chipmunk (Tamias sibiricus) in Northeastern Asia and Population Substructure in South Korea

  • Lee, Mu-Yeong;Lissovsky, Andrey A.;Park, Sun-Kyung;Obolenskaya, Ekaterina V.;Dokuchaev, Nikolay E.;Zhang, Ya-Ping;Yu, Li;Kim, Young-Jun;Voloshina, Inna;Myslenkov, Alexander;Choi, Tae-Young;Min, Mi-Sook;Lee, Hang
    • Molecules and Cells
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    • 제26권6호
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    • pp.566-575
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    • 2008
  • Twenty-five chipmunk species occur in the world, of which only the Siberian chipmunk, Tamias sibiricus, inhabits Asia. To investigate mitochondrial cytochrome b sequence variations and population structure of the Siberian chipmunk in northeastern Asia, we examined mitochondrial cytochrome b sequences (1140 bp) from 3 countries. Analyses of 41 individuals from South Korea and 33 individuals from Russia and northeast China resulted in 37 haplotypes and 27 haplotypes, respectively. There were no shared haplotypes between South Korea and Russia - northeast China. Phylogenetic trees and network analysis showed 2 major maternal lineages for haplotypes, referred to as the S and R lineages. Haplotype grouping in each cluster was nearly coincident with its geographic affinity. In particular, 3 distinct groups were found that mostly clustered in the northern, central and southern parts of South Korea. Nucleotide diversity of the S lineage was twice that of lineage R. The divergence between S and R lineages was estimated to be 2.98-0.98 Myr. During the ice age, there may have been at least 2 refuges in South Korea and Russia - northeast China. The sequence variation between the S and R lineages was 11.3% (K2P), which is indicative of specific recognition in rodents. These results suggest that T. sibiricus from South Korea could be considered a separate species. However, additional information, such as details of distribution, nuclear genes data or morphology, is required to strengthen this hypothesis.

농촌(農村) 주민(住民)들의 의료필요도(醫療必要度)에 관(關)한 연구(硏究) (A Study Concerning Health Needs in Rural Korea)

  • 이성관;김두희;정종학;정극수;박상빈;최정헌;홍순호;라진훈
    • Journal of Preventive Medicine and Public Health
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    • 제7권1호
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    • pp.29-94
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    • 1974
  • Today most developed countries provide modern medical care for most of the population. The rural area is the more neglected area in the medical and health field. In public health, the philosophy is that medical care for in maintenance of health is a basic right of man; it should not be discriminated against racial, environmental or financial situations. The deficiency of the medical care system, cultural bias, economic development, and ignorance of the residents about health care brought about the shortage of medical personnel and facilities on the rural areas. Moreover, medical students and physicians have been taught less about rural health care than about urban health care. Medical care, therefore, is insufficient in terms of health care personnel/and facilities in rural areas. Under such a situation, there is growing concern about the health problems among the rural population. The findings presented in this report are useful measures of the major health problems and even more important, as a guide to planning for improved medical care systems. It is hoped that findings from this study will be useful to those responsible for improving the delivery of health service for the rural population. Objectives: -to determine the health status of the residents in the rural areas. -to assess the rural population's needs in terms of health and medical care. -to make recommendations concerning improvement in the delivery of health and medical care for the rural population. Procedures: For the sampling design, the ideal would be to sample according to the proportion of the composition age-groups. As the health problems would be different by group, the sample was divided into 10 different age-groups. If the sample were allocated by proportion of composition of each age group, some age groups would be too small to estimate the health problem. The sample size of each age-group population was 100 people/age-groups. Personal interviews were conducted by specially trained medical students. The interviews dealt at length with current health status, medical care problems, utilization of medical services, medical cost paid for medical care and attitudes toward health. In addition, more information was gained from the public health field, including environmental sanitation, maternal and child health, family planning, tuberculosis control, and dental health. The sample Sample size was one fourth of total population: 1,438 The aged 10-14 years showed the largest number of 254 and the aged under one year was the smallest number of 81. Participation in examination Examination sessions usually were held in the morning every Tuesday, Wenesday, and Thursday for 3 hours at each session at the Namchun Health station. In general, the rate of participation in medical examination was low especially in ages between 10-19 years old. The highest rate of participation among are groups was the under one year age-group by 100 percent. The lowest use rate as low as 3% of those in the age-groups 10-19 years who are attending junior and senior high school in Taegu city so the time was not convenient for them to recieve examinations. Among the over 20 years old group, the rate of participation of female was higher than that of males. The results are as follows: A. Publie health problems Population: The number of pre-school age group who required child health was 724, among them infants numbered 96. Number of eligible women aged 15-44 years was 1,279, and women with husband who need maternal health numbered 700. The age-group of 65 years or older was 201 needed more health care and 65 of them had disabilities. (Table 2). Environmental sanitation: Seventy-nine percent of the residents relied upon well water as a primary source of dringking water. Ninety-three percent of the drinking water supply was rated as unfited quality for drinking. More than 90% of latrines were unhygienic, in structure design and sanitation (Table 15). Maternal and child health: Maternal health Average number of pregnancies of eligible women was 4 times. There was almost no pre- and post-natal care. Pregnancy wastage Still births was 33 per 1,000 live births. Spontaneous abortion was 156 per 1,000 live births. Induced abortion was 137 per 1,000 live births. Delivery condition More than 90 percent of deliveries were conducted at home. Attendants at last delivery were laymen by 76% and delivery without attendants was 14%. The rate of non-sterilized scissors as an instrument used to cut the umbilical cord was as high as 54% and of sickles was 14%. The rate of difficult delivery counted for 3%. Maternal death rate estimates about 35 per 10,000 live births. Child health Consultation rate for child health was almost non existant. In general, vaccination rate of children was low; vaccination rates for children aged 0-5 years with BCG and small pox were 34 and 28 percent respectively. The rate of vaccination with DPT and Polio were 23 and 25% respectively but the rate of the complete three injections were as low as 5 and 3% respectively. The number of dead children was 280 per 1,000 living children. Infants death rate was 45 per 1,000 live births (Table 16), Family planning: Approval rate of married women for family planning was as high as 86%. The rate of experiences of contraception in the past was 51%. The current rate of contraception was 37%. Willingness to use contraception in the future was as high as 86% (Table 17). Tuberculosis control: Number of registration patients at the health center currently was 25. The number indicates one eighth of estimate number of tuberculosis in the area. Number of discharged cases in the past accounted for 79 which showed 50% of active cases when discharged time. Rate of complete treatment among reasons of discharge in the past as low as 28%. There needs to be a follow up observation of the discharged cases (Table 18). Dental problems: More than 50% of the total population have at least one or more dental problems. (Table 19) B. Medical care problems Incidence rate: 1. In one month Incidence rate of medical care problems during one month was 19.6 percent. Among these health problems which required rest at home were 11.8 percent. The estimated number of patients in the total population is 1,206. The health problems reported most frequently in interviews during one month are: GI trouble, respiratory disease, neuralgia, skin disease, and communicable disease-in that order, The rate of health problems by age groups was highest in the 1-4 age group and in the 60 years or over age group, the lowest rate was the 10-14 year age group. In general, 0-29 year age group except the 1-4 year age group was low incidence rate. After 30 years old the rate of health problems increases gradually with aging. Eighty-three percent of health problems that occured during one month were solved by primary medical care procedures. Seventeen percent of health problems needed secondary care. Days rested at home because of illness during one month were 0.7 days per interviewee and 8days per patient and it accounts for 2,161 days for the total productive population in the area. (Table 20) 2. In a year The incidence rate of medical care problems during a year was 74.8%, among them health problems which required rest at home was 37 percent. Estimated number of patients in the total population during a year was 4,600. The health problems that occured most frequently among the interviewees during a year were: Cold (30%), GI trouble (18), respiratory disease (11), anemia (10), diarrhea (10), neuralgia (10), parasite disease (9), ENT (7), skin (7), headache (7), trauma (4), communicable disease (3), and circulatory disease (3) -in that order. The rate of health problems by age groups was highest in the infants group, thereafter the rate decreased gradually until the age 15-19 year age group which showed the lowest, and then the rate increased gradually with aging. Eighty-seven percent of health problems during a year were solved by primary medical care. Thirteen percent of them needed secondary medical care procedures. Days rested at home because of illness during a year were 16 days per interviewee and 44 days per patient and it accounted for 57,335 days lost among productive age group in the area (Table 21). Among those given medical examination, the conditions observed most frequently were respiratory disease, GI trouble, parasite disease, neuralgia, skin disease, trauma, tuberculosis, anemia, chronic obstructive lung disease, eye disorders-in that order (Table 22). The main health problems required secondary medical care are as fellows: (previous page). Utilization of medical care (treatment) The rate of treatment by various medical facilities for all health problems during one month was 73 percent. The rate of receiving of medical care of those who have health problems which required rest at home was 52% while the rate of those who have health problems which did not required rest was 61 percent (Table 23). The rate of receiving of medical care for all health problems during a year was 67 percent. The rate of receiving of medical care of those who have health problems which required rest at home was 82 percent while the rate of those who have health problems which did not required rest was as low as 53 percent (Table 24). Types of medical facilitied used were as follows: Hospital and clinics: 32-35% Herb clinics: 9-10% Drugstore: 53-58% Hospitalization Rate of hospitalization was 1.7% and the estimate number of hospitalizations among the total population during a year will be 107 persons (Table 25). Medical cost: Average medical cost per person during one month and a year were 171 and 2,800 won respectively. Average medical cost per patient during one month and a year were 1,109 and 3,740 won respectively. Average cost per household during a year was 15,800 won (Table 26, 27). Solution measures for health and medical care problems in rural area: A. Health problems which could be solved by paramedical workers such as nurses, midwives and aid nurses etc. are as follows: 1. Improvement of environmental sanitation 2. MCH except medical care problems 3. Family planning except surgical intervention 4. Tuberculosis control except diagnosis and prescription 5. Dental care except operational intervention 6. Health education for residents for improvement of utilization of medical facilities and early diagnosis etc. B. Medical care problems 1. Eighty-five percent of health problems could be solved by primary care procedures by general practitioners. 2. Fifteen percent of health problems need secondary medical procedures by a specialist. C. Medical cost Concidering the economic situation in rural area the amount of 2,062 won per residents during a year will be burdensome, so financial assistance is needed gorvernment to solve health and medical care problems for rural people.

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강원도 일부 도시들의 토지이용 및 녹지구조 (Land Use and Greenspace Structure in Several Cities of Kangwon Province)

  • 조현길;이기의;윤영활;서옥하
    • 한국조경학회지
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    • 제25권4호
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    • pp.171-183
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    • 1998
  • The purpose of this study was to analyze urban greenspace area and vegetation structure by land use types for both Chuncheon and Kangleung. Natural and agricultural lands were predominant in the study cites, as 75-80% of total area. Residential lands accounted for about 10%, and commercial and industrial lands(including transportation), 5-10%. Only 10-20% of urban residential and commercial area was covered with greenspace. Woody plant cover was 12-13%, and tree density was 1.5 trees/100$m^2$ for urban lands(all land use types except natural land) in both cities. The tree-age structure was largely characterized by young, growing tree population, and species diversity within a diameter class decreases as the diameter classes get larger. Urban lands of both cities had quite a similar species composition of woody plants (similarity index of 0.65). Street trees in Chuncheon were intensively pruned annually to protect the above ground utility lines. Some strategies were explored to solve problems found in the existing greenspace structures. They included increase of biomass and greenspace area through minimization of unnecessary impervious surfaces, creation of multilayered and multiaged vegetation structures, relocation of above ground utility lines and avoidance of intensive tree pruning, and establishment of greenspace proximity and connectivity.

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한반도 특산식물 개느삼의 개체군 특성 (Population Characteristics of Echinosophora koreensis (Nakai) Nakai, a Endemic Plants in Korea)

  • 김소담;문애라;안종빈;정지영;박완근;손성원
    • 한국환경생태학회지
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    • 제34권1호
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    • pp.18-26
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    • 2020
  • 개느삼은 한반도의 일부 지역에 제한적으로 분포하는 특산식물이며, IUCN Red List의 'Endangered'로 지정된 희귀식물이다. 본 연구는 자생지의 환경변화로 쇠퇴 위협이 있는 개느삼의 분포 패턴과 개체군 구조를 조사 분석하여 향후 개느삼 개체군의 동태 및 지속성 파악을 위한 기초 자료 활용에 목적이 있다. 개느삼 개체군의 특성을 파악하기 위해 양구, 춘천, 홍천 3개 지역에 각각 2~3개의 대방형구(20m×30m)를 능선을 기준으로 설정하고, 대방형구 안에 4~7개 Transect상의 소방형구(1m×1m)를 2m 간격으로 각각 10개씩 총 530개를 설정하여 출현 개체 수 및 결실 개체 수, 개체 높이 등을 측정하였다. 확보된 종발생정보를 IUCN Red List ver 3.1의 평가기준 B를 적용하여 기존 IUCN에 평가된 범주와 비교분석하였다. 조사된 세 개 지역의 평균 개체 밀도는 3.47본/㎡로 나타났으며, 지역별로 양구 3.95본/㎡, 춘천 3.37본/㎡, 홍천 2.87본/㎡이었다. 한편, 개체군의 결실률(결실 수/개체 수)은 0.0038으로 전체 출현 개체 1,837본 중에 7본만이 결실된 것으로 나타나 생식생장(sexual reproductive) 보다는 영양생장(vegetative reproduction) 비율이 매우 높을 것으로 추정된다. 조사된 세 지역의 소방형구 개체 밀도의 분포 경향을 분석한 결과, 개느삼은 수관 열림이 높은 산지 능선을 중심으로 수관 열림이 낮은 숲 중심부로 갈수록 개체 밀도가 감소하는 경향을 보여줌으로써, 광량이 개느삼 개체의 생육에 매우 중요한 요소일 것으로 추정된다. 한편, 방형구내 출현하는 전체 개체의 높이를 분석한 결과 2.3~68.5cm로 나타났으며, 평균 20.1cm로 조사되었다. 개체 높이를 바탕으로 개느삼 개체군의 stage-structure를 분석한 결과 15~20cm를 기점으로 개체 높이가 높아질수록 점차 출현빈도가 감소하는 경향을 보여주었으며, seedling으로 추정되는 10cm 이하의 개체들의 비율도 매우 낮게 나타남으로써 향후 모니터링 자료를 바탕으로 개체군의 지속성에 대한 분석이 필요할 것으로 보인다. 한편, 확보한 종발생정보를 바탕으로 산출된 점유면적은 200㎢로 나타나 IUCN Red List 기준(criteria) B 적용 시 EN 범주를 충족하는 것으로 나타났다.

Chikuma 강 중류 수역에서 하안 보호 공사가 Stenopsyche marmorata (Trichoptera)에 미치는 영향 (Central Japan) (Impact of Bank-protection Work on Stenopsyche marmorata (Trichoptera) in the Middle Reaches of the Chikuma River in Central Japan)

  • Fukunaga, Yachiyo;Kimura, Goro;Kimio, Hirabayashi
    • 생태와환경
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    • 제37권4호통권109호
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    • pp.400-405
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    • 2004
  • 동계에 Chikuma 강 중류 수역에서 대규모 하안 보호 공사가 시행된 이후로 강의 하상 구에 급격한 변화가 나타났다. 본 연구는 연속하는 춘계-하계 기간 동안 날도래목 곤충의 일종인 Stenopsyche marmorata의 밀도 유형에 대한 하안 보호 공사의 영향을 평가하기 위해 수행되었다. Light trap을 이용하여 날도래 성충을 포획하여 분석한 결과에 의하면, S. marmorata에 대한 일일 포획의 양상과 포획 개체의 누적 밀도는 공사 전후에 상이하게 나타났다. 즉, 공사 후의 조사 기간 동안일일 포획 성충의 밀도는 약간 증가하였다. 이 결과는 공사 지역에서 S. marmorata 유충 개체군의 연령 구조가 바뀌었고, 하안 보호 공사가 Chikuma강 생태계에 서식하는 날도래 성충의 밀도 패턴에 영향을 미쳤음을 시사한다.