• Title/Summary/Keyword: tree age

Search Result 537, Processing Time 0.031 seconds

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

  • 조현길;이기의;윤영활;서옥하
    • Journal of the Korean Institute of Landscape Architecture
    • /
    • v.25 no.4
    • /
    • pp.171-183
    • /
    • 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.

  • PDF

A Study on Factors of Management of Diabetes Mellitus using Data Mining (데이터 마이닝을 이용한 당뇨환자의 관리요인에 관한 연구)

  • Kim, Yoo-Mi;Chang, Dong-Min;Kim, Sung-Soo;Park, Il-Su;Kang, Sung-Hong
    • Journal of the Korea Academia-Industrial cooperation Society
    • /
    • v.10 no.5
    • /
    • pp.1100-1108
    • /
    • 2009
  • The Objectives: The purpose of this study is to identify the factors related to management of DM in Korea. Methods: The subjects selected by using data of National Health and Nutrition Survey(NHANS) in 2005 were 415 adults, aged 20 and older, and diagnosed with DM. This study used data mining algorithms. This study validated the predictive power of data mining algorithms by comparing the performance of logistic regression, decision tree, and Neural Network on the basic of validation, it was found that the model performance of decision tree was the best among the above three techniques. Result: First, awareness of DM was positively associated with age, residential area, and job. The most important factor of DM awareness is age. Awareness rate of DM with 52 age over is 76.1%. Among the ${\geq}52$ age group, an important factor is family history. Among patients who are 52 years or over with family history of DM, an important factor is job. The awareness rate of patients who are 52 age over, family, history of DM, and professionals is 95.0%. Second, treatment of DM was also positively associated with awareness, region, and job. The most important factor of DM treatment is DM awareness. Treatment rate of patients who are aware of DM is 84.8%. Among patients who have awareness of DM, an important factor is region. The awareness rate of patients who are aware of DM in rural area is 10.4%. Conclusion: Finally, the result of analysis suggest that DM management programs should consider group characteristic of DM patients.

Yields and Fruit Quality of Different Aged Walnut Trees (Juglans sinensis Dode) Derived from Seedlings in Gimcheon (김천지역 실생묘 유래 호두나무의 수령별 수확량 및 과실 품질)

  • Oh, Sung-Il;Lee, Uk;Kim, Chul-Woo
    • Journal of Korean Society of Forest Science
    • /
    • v.109 no.3
    • /
    • pp.325-332
    • /
    • 2020
  • This study was conducted on cultivation farms in the Gimcheon area, which is the main production area of walnuts, in order to compare and analyze the yield and fruit quality of walnut trees (Juglans sinensis Dode) derived from seedlings. The official trees were classified into nine classes from 10 to 60 years old, and a total of 135 trees were selected, with 15 trees selected for each grade. The growth and fruit characteristics for each age group were then examined. The average tree height was 10.3 m, and the average crown area was 63.7 ㎡. The average number of fruit settings per tree was 573.1, with the largest number of walnuts per tree at 35 years (974.0 walnuts), and the lowest walnuts per tree at 10 years (124.7 walnuts). In addition, the number of fruit settings per bearing mother branch in 35 year old trees was the highest at 3.1. The average weight for each fruit type was found to be 58.7 ± 4.0 g of walnuts in green peel, 10.5 ± 0.5 g of dried shell walnuts, and 4.9 ± 0.2 g of walnuts, respectively. The average yield by fruit type was 32.5 ± 13.8 kg of walnuts in green peel, 5.9 ± 2.5 kg of dried shell walnut, and 2.8 ± 1.2 kg of walnuts. The yield was positively correlated with the crown area, the number of fruits setting per bearing mother branch, and the number of fruits setting per 1 ㎥. The formula used to estimate the yield per tree by age was calculated as y = 8993.9 ln (tree age-9) 8230.3, R2 = 0.8531 (walnut in green peel) and y = 1647.1 ln (tree age-9) 1442.1, R2 = 0.8527 (dried shell walnut).

Analysis of Tree Growth Characteristics by First and Second Thinning in Korean White Pine Plantations (잣나무 인공림의 1차 및 2차 간벌에 따른 입목생장 특성 분석)

  • Lee, Daesung;Jung, Sunghoon;Choi, Jungkee
    • Journal of Korean Society of Forest Science
    • /
    • v.111 no.1
    • /
    • pp.150-164
    • /
    • 2022
  • This study was conducted to provide basic information for the development of silvicultural guidelines and manuals. This was achieved through analysis of tree and stand characteristics according to the first and second thinning in Korean white pine plantations. Data were collected from permanent plots installed at Korean white pine plantations according to thinning intensity, and residual tree and stand variables, including diameter at breast height (DBH), volume, and mortality at age 19-43, were analyzed using data repeatedly collected in 4-5 measurements by experiments. According to one-way variance of analysis, tree DBH and volume were significantly different according to thinning intensity (p<0.05). DBH distribution was skewed to the left side over time as thinning intensity was heavier. Thus, tree DBH values were larger in heavy thinning plots with increased age. The periodic annual increment (PAI) of DBH was higher with heavier thinning intensity and fewer years after thinning. The PAI range by thinning intensity was 0.48-0.95 cm/year at age 19-24. In addition, the PAI increased in heavy thinning plots after the second thinning; The PAI range by thinning intensity was 0.29-0.67 cm/year after the second thinning at age 37-42. The PAI of tree volume differed according to thinning intensity, and the PAI value did not decrease obviously, in contrast to the pattern of the DBH PAI. Stand volume was generally higher in high-density stands, and the PAI of stand volume was high in unthinned and light thinning plots. Mortality was highest in unthinned plots, and the differences in mortality according to thinning intensity increased over time. Consequently, the growth of DBH and tree volume was lower as stand density increased, but this growth was facilitated with appropriate first and second thinning operations.

Evaluation of Damaged Stand Volume in Burned Area of Mt. Weol-A using Remotely Sensed Data (위성자료를 이용한 산화지의 입목 손실량 평가)

  • Ma, Ho-Seop;Chung, Young-Gwan;Jung, Su-Young;Choi, Dong-Wook
    • Journal of the Korean Association of Geographic Information Studies
    • /
    • v.2 no.2
    • /
    • pp.79-86
    • /
    • 1999
  • This study was carried out to estimate the area of damaged forest and the volume of stand tree in burned area, Mt. Weol-A in eastern Chinju, Korea using digital maps derived from supervised classification of Landsat thematic mapper(TM) imagery as reference data. Criterion laser estimator and WinDENDRO$^{tm}$(v. 6.3b) system as a computer-aided tree ring measuring system were used to measure a volume and age of sampled tree. The sample site had been chosen in unburned areas having the same terrain condition and forest type of burned areas. The tree age, diameter at breast height, tree height and volume of the sample tree selected from sample site in unburned area were 27years, 20.9cm, 9.7m and $0.1396m^3$ respectively. Total stand volume of sample site was estimated $2.9316m^3$/0.04ha, Damaged stand volume evaluated to about $16,007m^3$ in the burned area of 218.4ha.

  • PDF

Effects of Biological and Environmental Factors on the Occurrence of Chestnut Blight in Chestnut Tree Plantations (밤나무 재배지에서의 생물적, 환경적 요인이 밤나무 줄기마름병 발생에 미치는 영향)

  • Lee, Sang-Hyun;Kim, Kyung-Hee;Byun, Jae-Kyung;Lee, Jong Kyu;Moon, Byung-Ju
    • Journal of Korean Society of Forest Science
    • /
    • v.95 no.1
    • /
    • pp.139-144
    • /
    • 2006
  • Chestnut trees have been severely damaged by the various cankers in Korea. Field surveys for elucidating the relationships between disease occurrence and environmental factors, i.e., tree age, temperature, rainfall precipitation, direction, degree of slope, chemical properties of soils, and so on, were carried out in the chestnut tree plantations located at Gyeongnam, Jeonnam, Chungnam, and Gyeonggi-Do Province. Totally, one thousand and one hundred thirty seven trees from 36 experiment plots were investigated. Trees infected by at least one of the canker fungi were estimated up to 66%. The most severely infested area was Sunchon in Jeonnam Province with the rate of 80%, while the most lightly infested area was Kongju in Chungnam Province with 39%. Disease occurrence was found to be highly correlated with tree age. The disease occurred most frequently on trees ranged from 7 to 12 years old, while it was relatively low on trees below 5 years old or above 25 years old. Canker positions on the tree formed by the pathogenic fungi were most often at 1.6-2.0m above the ground. Over five hundreds bark samples from the canker area on the tree were collected and the pathogenic fungi were isolated. The most commonly isolated fungus was identified as Cryphonectria parasitica, the chestnut blight fungus.

Global Warming Detected by Tree Rings from Mongolia

  • Nachin, Baatarbileg;Jacoby, Gordon C.
    • The Korean Journal of Quaternary Research
    • /
    • v.17 no.2
    • /
    • pp.55-61
    • /
    • 2003
  • In the year 2000 we culminated a successful five year investigation of climate change by completing a preliminary east-west transect across Mongolia. An earlier tree-ring study at Tarvagatay Pass, Mongolia indicated unusual warming during the 20th century similar to other paleo-investigations of the northern hemisphere. This record had represented one of the few tree-ring records for central Asia. New data from several sites in western Mongolia confirmed the preliminary temperature. The highest twenty-year growth period for the composite record is from 1973-1994. The western Mongolian record was significantly correlated with the Taimyr Peninsula and two northern hemisphere temperature reconstructions reflecting large-scale temperature patterns while showing some important regional differences. These differences should prove useful for climate models. We have also developed a millennial length temperature-sensitive record at the Solongotyin Davaa site (formerly Tarvagatay Pass) using relict wood and living trees. Conspicuous features over the last 1000 years are a century scale temperature decline punctuated by the end of the Little Ice Age in the late-1800s and 20th century warming. The record also shows a cold period early in the 12th century and warm intervals late in the 10th, early in the 15th and at end of the 18th centuries. Despite a limited sample size before 900 AD, the long Solongotyin Davaa record is useful in indicating severe cold events and suggests some cold intervals nearly as severe. These tree ring series, spanning much of the circumpolar northern treeline, have been compiled to create a long-term reconstruction of the Earth's temperature over centuries. The new chronology, in addition to its value as a detailed record of Mongolian climate, provides independent corroboration for such hemispheric and global reconstructions and their indications of unusual warming during the 20th century.

  • PDF

A Comparison Study on the Survival Characteristics of Big Old Sophora japonica and Zelkova serrata Called 'Goe'

  • Rho, Jae-Hyun;Han, Sang Yup;Kim, Sang Beom
    • Journal of People, Plants, and Environment
    • /
    • v.23 no.1
    • /
    • pp.115-123
    • /
    • 2020
  • With the aim of accumulating data that can be used to infer the basis for the acculturation of trees called 'Goe,' this study aims to identify the survival status of the pagoda and zelkova trees known as 'Goe' trees by comparing and analyzing the status of pagoda trees (Sophora japonica) and zelkova tree (Zelkova serrata) designated as a protected tree in Korea. The results of this study are as follows; Zelkova serrata designated as a protected tree grows the most, with 2,147 trees (29.4%) in Cheonnam, followed by Chungnam (16.5%) and Gyeongbuk (14.4%). However, Sophora japonica showed a different result from zelkova Serrata as the total number of 210 Sophora japonica (55.7%) in Gyeongbuk and Daegu is much larger than that of zelkova Serrata. As a result, in the Yeongnam region, where the Confucianism of Yeongnam was actively practiced, the existence of Sophora japonica is much larger than that of the Zelkova Serrata, which is not a coincidence, and it is difficult to determine it only based on their flora and planting distribution. Results of comparing protected trees of Sophora japonica and Zelkova Serrata showed that the average age of Zelkova Serrata wass 289 years, while that of Sophora japonica was 302 years, and that the average height of Zelkova Serrata wass 18 m, which is higher than the height of 16 m of Sophora japonica. The average diameter at breast height of Zelkova Serrata was 398 cm and that of Sophora japonica was 314 cm, which indicates that Zelkova Serrata is relatively big. Therefore, it can be assumed that Zelkova Serrata has a larger growth potential than Sophora japonica, and the possibility of growth as a big tree is also high, but it seems that the explanation that "they are relatively long-lived" is not clearly determined.

Ecological Studies on Several Forest Communities in Kwangnung. A Study of the Site Index and the ground vegetation of Larch (광릉삼림의 생태학적 연구 낙엽송의 Site Index와 임상식생에 관하여)

  • 차종환
    • Journal of Plant Biology
    • /
    • v.9 no.1_2
    • /
    • pp.7-16
    • /
    • 1966
  • In order to determine the factors related to site quality, 13 areas of Larch growing in the Kwangung and its vicinity forest as sample plots, were examined. Sample plots included various site classes as well as age classes. Three were divided into two groups (major and minor trees). Average height of dominant trees was determined through messurement of 5 to 6 dominant tree in each sample plots. Average height of dominant 30 year-old trees was the basis for site index. A Standard Yield Table for the larch produced in Kwangnung forest was made by various data, which included age class 5, ranging from 10 to 45 years. The relationship of the height of the trees, the site conditions, and ground vegetation are investigated in this paper. The site indexes of 40 forest class age in 28-B and 28-G forest classes of the larch associations for ground vegetation had comparatively rarge differences due to the sampled areas. The relation of the direction of forest communities to the height and the diameter of the tree shwoed that its communiteis of northest and northwest parts appeared higher valueof the height and the diameter. The diameter and the height of trees were closely realted to each other. The samller the occupied area per tree and the smaller the average distance among trees, the more density was increased. The larger the density was the lower height of the trees. In the ground vegetation of the larch communities, there seems to be a definite correlation between the height of trees and the occupied area per tree or the average distance among the trees. The height of trees and site index of two larch communities were as follow: 28-B forest class site index 20.8, height 24.0m, 28-G forest class site index 18.4, height 20.9m. The ground layer was analyzed by the method of Quadrat(20/20sq. cm) with an interval of 1M. It set up 40 Quadrats of the larch communiteis. The community structure of the ground vegetation of two larch was analyzed, and important value was calculated and then evaluated. The ground vegetation under the larch had developed Burmannii Beauv stratal society below the 28-B and 28-G the forest class. Accordingly, the first important value of Burmannii Beauv was found in two ground vegetation below the larch. Therefore, this species could be quantitatively considered as the forest indicator species. Common species of each community appeared 18 species out of 34 species in the ground vegetation under two larch communities. The ground vegetation of the 28-B forest class showed more than that of the 28-G forest class. the similarity of the ground vegetation was measrued by the Frequency Index Community Coefficient. The differences between the associations were lcearly manifested by the ground vegetation tested by Gleason's Frequency Index of Community Coefficient for the analysis of each stratal society of all associations. According to F.I.C.C. the ground vegetation under two larch(28-B and 28-G) forest classes showed higher value. An investigation into the relationship of physical and chemical properties of soil and site was considered the next step to be taken in the study of the larch site classification.

  • PDF

Population Dynamics of Pinus densiflora for. erecta at Sokwang-Ri, Uljin-Gun in Southeastern Korea

  • Yun, Chung-Weon;Bae, Kwan-Ho;Hong, Sung-Cheon
    • The Korean Journal of Ecology
    • /
    • v.24 no.6
    • /
    • pp.341-348
    • /
    • 2001
  • Population dynamics of the oldest relic stand of Pinus densiflora for. erecta which remains as a status of patch in Sokwang-Ri area, Uljin-Gun, was studied to provide the basic data for conservation of the oldest pine stand in Korea. The upper slope site and ridge site including total 12 plots mainly represented Pinus densiflora for. erecta and Quercus mongolica. These two tree species showed reverse J-shaped distribution. From this information, it was concluded that intensive interspecific competition between two species could be occurring. Age distribution of P. densiflora for. erecta on the sites above middle slope area was indicated bi-modal type or tri-modal type which was known as an age structure of climax forest. Therefore, it was estimated that Pinus densiflora for. erecta population could be continuously maintained in the each patch above middle slope area. In the valley sites, hardwood species such as Q. mongolica, Q. variabilis, Styrax obassia and Acer pseudosieboldianum occupied most part of the under crown-cover area and their seedlings and saplings were developing into the closed upper layer crown because the height of upper layer crown reached about 35 meters and such a high crown height was more suitable for light utilization by plants of under layer. The growth patterns were mainly fluctuated for the entire life time of the oldest tree caused by frequent disturbance. And the initial growth curves of the mature trees and suppressed juvenile trees showed different tendencies along the sites.

  • PDF