• 제목/요약/키워드: deciduous

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온대북부형 낙엽활엽수림의 디지털 카메라 반복 이미지를 활용한 식물계절 분석 (Phenophase Extraction from Repeat Digital Photography in the Northern Temperate Type Deciduous Broadleaf Forest)

  • 한상학;윤충원;이상훈
    • 한국산림과학회지
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    • 제109권4호
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    • pp.361-370
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    • 2020
  • 매년 반복되는 식물의 생활사를 장기적으로 관측하는 것은 기후변화 반응을 감지하는데 있어 가장 단순한 방법이며, 중요한 지표로 인식되고 있다. 반복 디지털 이미지를 이용한 식물계절 변화 관찰 방법은 전통적(현장에서 전문가에 의해 관찰) 방법과 위성원격탐사(위성영상의 식생지수를 활용한 위성원격 관찰)의 한계를 보완한 방법이다. 본 연구는 디지털 카메라를 기반으로 한 반복 이미지로부터 식물계절 변화 관측과 계절현상을 정량화하기 위하여 점봉산 산림생태계를 대상으로 하였다. 한반도 전역에 분포하는 신갈나무림(낙엽활엽수림)과 상록침엽수림의 대표 수종인 소나무를 선정하여 식물계절 특성에 따른 경향성을 파악하고자 하였다. RGB 채널 이미지 데이터로부터 식생지수(Gcc)를 산출하였다. Gcc 진폭의 크기는 상록침엽수림이 낙엽활엽수림 보다 작았으며, Gcc의 기울기(봄철 증가와 가을철 감소)는 상록침엽수림이 낙엽활엽수림과 비교하여 완만하였다. 소나무림은 생장의 시작(UD)이 신갈나무림에 보다 빨랐고, 생장의 종료(RD)는 늦은 것으로 나타났다. 식물계절 현상의 정확도 검증은 RMSE가 0.008(ROI1)과 0.006(ROI3)으로 높은 정확도를 보였다. 이러한 결과는 온대북부형 낙엽활엽수림의 Gcc 궤적의 경향성을 잘 반영하였으며, 디지털 카메라를 이용한 반복 이미지 관측 방법이 식물계절 변화 관측에 있어 유용할 것으로 판단된다.

신모에 의한 하악전돌증의 치험일예 (A CASE REPORT OF MANDIBULAR PROGNATHISM TREATED WITH THE CHINCAP)

  • 남동석
    • 대한치과의사협회지
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    • 제16권9호통권112호
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    • pp.689-693
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    • 1978
  • A girl (Hellman dental age IIC) with anterior cross bite was treated by means of the chincap and occlusal equilibration on deciduous canines. Following results were obtained; 1) The cross bite was corrected after 12 weeks of active treatment. 2) The terminal plane of deciduous molars had become 'a class II tendency' 3) The axial inclination of lower incisors were changed significantly.

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낙동정맥 절구골 지역의 식물군집구조 (Vegetation Structure of Jeolgu Valley in the Nakdong-Jeongmaek)

  • 조현서;이수동;김미정
    • 한국환경생태학회지
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    • 제26권5호
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    • pp.770-779
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    • 2012
  • 낙동정맥 절구골의 식생구조를 파악하고자 계곡부 약 3km 구간을 대상으로 $10m{\times}10m(100m^2)$ 조사구 29개소를 설치하여 식물군집구조 조사를 실시하였다. TWINSPAN classification에 의한 군락 분류 결과 소나무군락, 낙엽활엽수군락, 굴참나무군락, 신갈나무군락, 일본잎갈나무군락 5개 유형으로 분류되었다. 계곡부와 북사면에는 습윤지성 낙엽활엽수와 참나무류가 주로 분포하였고 일본잎갈나무군락은 당분간 현상태를 유지하겠으나 하층의 들메나무, 산뽕나무, 고로쇠나무 등 낙엽성 활엽수의 세력이 우세해지고 있어 장차 이들 종으로의 천이가 기대되었다. 군락별 종다양도지수는 0.9665~1.2450 범위로 낙동정맥 타 지역에 비해 높은 것으로 나타났다.

The relationships between the arrangement of teeth, root resorption, and dental maturity in bovine mandibular incisors

  • An, Jin-kyu;Matsumoto, Yoshiro;Ono, Takashi
    • 대한치과교정학회지
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    • 제47권6호
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    • pp.365-374
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    • 2017
  • Objective: The objective of this study is to investigate the eruption pattern and root resorption of the bovine anterior dentition in relation to growth-related parameters based on dental maturity. Methods: A cross-sectional study was conducted on 110 bovine anterior mandibles by using standard radiography, cone-beam computed tomography (CBCT), and actual measurements. We determined the relationships between the stages of dental maturity by using a modification of Demirjian's method and various growth-related parameters, such as the activity of the root-resorbing tissue and mobility of the deciduous teeth. The correlation of growth-related parameters with interdental spacing and distal unusual root resorption (DRR) of the deciduous fourth incisor was assessed. The cause of mesial unusual root resorption (MRR) of the deciduous fourth incisor was determined on the basis of the arrangement of the permanent third incisor. Results: An independent t-test and chi-square test indicated significant differences in growth-related parameters associated with dental arch length discrepancy and factors related to the shedding of deciduous teeth between the low and high dental maturity groups. The samples with interdental spacing and DRR showed a larger sum of mesiodistal permanent crown widths and higher dental maturity than did the respective controls. Samples with MRR tended to show a lingually rotated distal tip of the adjacent tooth crown. Conclusions: Dental maturity has relevance to the interdental spaces and unusual root resorption of mixed dentition. The position of the adjacent tooth crown on CBCT may be correlated with the occurrence of unusual root resorption of the incisor.

Site suitability for conifer plantation and a new challenge to utilize deciduous trees

  • NAGASHIMA, Keiko
    • 한국자원식물학회:학술대회논문집
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    • 한국자원식물학회 2018년도 추계학술대회
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    • pp.24-24
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    • 2018
  • Degraded plantation forests are increasing because of unfavorable forestry conditions prevailing in Japan, including falling timber prices, increasing operational costs, and aging and declining forestry workforce. To remedy this situation, appropriate management strategy is required. This study introduces the challenges of Odai Town, Mie Prefecture that employed a new management strategy by evaluating site suitability for conifer forests and that proposes a new forest management regime of planting deciduous trees in unsuitable sites. The site suitability for conifer forests was evaluated from two aspects: the natural site conditions and the relationship among site conditions, growth, and damage by Anaglyptus subfasciatus Pic. in Cryptomeria japonica D. Don and Chamaecyparis obtusa Sieb. Et Zucc. forests. By analyzing the relationship among site conditions, growth, and insect damage based on field data obtained in plantation forests, growth evaluation and insect damage evaluation maps were developed. Based on the natural forest investigation, natural site condition maps for C. japonica and C. obtusa were established. Furthermore, by integrating these evaluation maps with the forest road maps showing the accessibility to the forest, the forest management regime for the whole plantation area of Odai Town was established. The forest management regime map indicates the sites suitable for forestry: suitable for long-rotation, short-rotation, and potential sites for short-rotation. The sites unsuitable for forestry were considered to be more suitable for broadleaved forests. Clear-cutting was conducted in a small area and different seral stage saplings (approximately 20 deciduous tree species) suitable to the site conditions were planted in an area of $80-120m^2$ protected by deer-fences. This might establish a forest composed of many species with a multilayer vertical forest structure in a short period. The planted saplings were distributed neither randomly nor uniformly to reflect the natural distribution of trees in the forest. A challenge to develop new products using the deciduous trees has started, such as wood chips for preparing smoked food, essential oil, and deodorizer. As these challenges have just begun, their effects on enhancing sustainable resource management are still being monitored. Even with the challenges, this regime can be of high value as a management strategy to remedy the situation of expansion of degraded forests in Japan.

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Community Ecological Revaluation of Acer pseudosieboldianum and Carpinus cordata in the Natural Deciduous Forest

  • Kim, Ji Hong;Kang, Sung Kee;Lim, Seon Mi
    • Journal of Forest and Environmental Science
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    • 제32권1호
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    • pp.74-81
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    • 2016
  • Classified into sub-tree of the growth-form, Acer pseudosieboldianum and Carpinus cordata hardly reach the uppermost canopy with limited height growth potentiality in the natural deciduous forest. However, the two species usually dominate lower stories of the forest, playing an important role in overall ecological characteristics in the forest. Based on the vegetation data of 106 $20m{\times}20m$ sample plots in Mt. Jumbong area, this study was carried out to evaluate ecological constitution by several quantitative analysis so as to understand the mechanism of the natural deciduous forest. The results indicated that individuals of A. pseudosieboldianum and C. cordata were absent or few in overstory, but emerged the most dominant species in midstory and understory, providing adequate proof of the ecological importance. The comparison of indices of succession between presented and predicted values in midstory did not make much difference, suggesting that the species composition would not change much and come close to steady state in midstory and understory. The pair combination of species association noted that A. pseudosieboldianum had significant positive association with C. cordata, Quercus mongolica, and Tilia amurensis had significant positive association with A. pseudosieboldianum, A. pictum subsp. mono and Fraxinus mandshurica but negative association with F. rhynchophylla. Being compared with other major canopy tree species in the study forest, the target species of A. pseudosieboldianum and C. cordata had strong regeneration strategies, partially characterized by large number of saplings and pole sized trees and high ratio of live crown, which indicated high shade tolerance to survive in the limited amount of light under the canopy. Even though A. pseudosieboldianum and C. cordata do not reach and occupy the canopy layer mainly due to the inherent growth form, they would have highest competitive potentiality to prosper and dominate in the midstory of the natural deciduous forest.

Comparison of Oribatid Mite (Acari : Oribatida) Communities among City, Suburban, and Natural Forest Ecosystems : Namsan, Kwangreung, and Mt. Jumbong

  • Lee, Joon-Ho;Park, Hong-Hyun;Kang, Bang-Hun;Jung, Chul-Eui;Choi, Seong-Sik
    • The Korean Journal of Ecology
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    • 제23권2호
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    • pp.107-112
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    • 2000
  • Comparison of oribatid mite community structures among Namsan, Kwangreung, and Mt, Jumbong, which receive different levels of environmental stress from severe to almost none, was made in coniferous and deciduous forests, respectively. The number of species of oribatid mites was significantly lower in Namsan and Mt. Jumbong than in Kwangreung in the coniferous forest (p<0.05). In the deciduous forests, the number of species of oribatid mites was significantly lower in Namsan than in Kwangreung and Mt. Jumbong. Dominant species in 3 regions were remarkably different. Similarity of the oribatid community between Namsan and Kwangreung was much higher (ca. 2 times) than similarities between Namsan and Mt. Jumbong. and Kwangreung and Mt Jumbong. Diversity index (H$^{\prime}$) value of oribatid communities in deciduous forests in Namsan, Kwangreung and Mt. Jumbong was 2.74, 2.78, and 2.87, respectively. Diversity (H$^{\prime}$) value of oribatid communities in coniferous forests in Namsan, Kwangreung and Mt. Jumbong was 2.83, 2.62, and 2.38, respectively. Namsan and Kwangreung were characterized as O-type in both coniferous and deciduous forests On the contrary, Mt. Jumbong was characterized as MG-type in MGP-I analysis.

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G대 부속 유치원생의 치면세균막 형성 및 구강건강실태에 관한 연구 (A Study on the Dental Plague Formation and the Oral Health Condition of Preschool Children in G College in Affiliation)

  • 이천희;장영호
    • 보건의료산업학회지
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    • 제4권2호
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    • pp.63-72
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    • 2010
  • The present study purposed to prevent oral diseases and to improve oral health in children. For this purpose, we selected 70 cases who are 5~7 years old preschoolers at the kindergarten affiliated to G College in Gyeongsangbukdo, and analyzed the general patterns of oral care and the relation of the patterns with dental plaque and deciduous dental caries in the children. Specifically, we conducted oral examination and applied pit and fissure sealant according to the eruption of deciduous molar and first molar. In addition, we executed the 1st and 2nd tooth brushing instruction (TBI), and surveyed S-OHI and PHP twice. Excluding 14 preschoolers who did not appear in the 2nd survey, we performed the study with 56 preschoolers and drew conclusions as follows. 1. The number of decayed or missed or filled teeth among deciduous teeth was 3 or more in 42.9% of female children, and 46.4% of male children, so male children showed a slightly higher rate. 2. The degree of dental plaque formation was $1.64{\pm}1.22$ among the surveyed children. 3. The oral health index was lower after TBI than before in all the children (P<.001). 4. Change in the oral health index was particularly larger in 7 year old female children (p<.005). 5. The patient hygiene performance index was lower after TBI than before in both the buccal surface and lingual surface of the children (p<.005). 6. The patient hygiene performance index was lower after TBI than before in all of male children's teeth except the right maxillary first deciduous molar (p<.001).

지리산국립공원 낙엽활엽수림 세 군락의 탄소저장량 평가 (Estimation of Carbon Storage in Three Cool-Temperate Broad-Leaved Deciduous Forests at Jirisan National Park, Korea)

  • 이나연
    • 환경생물
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    • 제30권2호
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    • pp.121-127
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    • 2012
  • 지리산국립공원 산림생태계의 탄소 수지에 관한 기초자료를 확보하기 위해 낙엽활엽수림에 대한 탄소저장량을 추정하였다. 지리산국립공원의 대표 낙엽활엽수림 군락을 중심으로 뱀사골 지구, 중산리 지구, 성삼재 지구로 나누어 조사구 ($30m{\times}30m$, 3지점)를 설치, 식생권과 토양권의 탄소저장량을 추정하였다. 식생권의 탄소량은 $107{\sim}119tC\;ha^{-1}$의 범위로 평균 약 $112tC\;ha^{-1}$ 정도의 양을 축적하고 있다. 또한 토양권의 탄소량은 $64{\sim}77tC\;ha^{-1}$의 범위로 평균 약 $66tC\;ha^{-1}$ 정도의 양을 축적하고 있다. 토양권과 식생권을 포함한 생태계 전체의 탄소저장량은 $167{\sim}184tC\;ha^{-1}$의 범위로 평균 약 $178tC\;ha^{-1}$ 정도의 양을 축적하고 있다. 값의 범위에서 알 수 있듯이 지구별 차이는 크게 나타나지 않았다. 다른 연구 결과와 비교하여 설악산국립공원을 비롯한 강원권 생태계를 제외하고 매우 많은 양의 탄소가 저장되어 있음을 알 수 있다.