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Effect of Temperature and Water Content of Soil on Creeping Bentgrass(Agrostis palustris Huds) Growth (토양의 온도와 수분이 크리핑 벤트그래스(Agrostis palustris Huds) 생육에 미치는 영향)

  • Lim, Seung-Hyun;Jeong, Jun-Ki;Kim, Ki-Dong;Joo, Young-Kyoo
    • Asian Journal of Turfgrass Science
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    • v.23 no.2
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    • pp.229-240
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    • 2009
  • The high temperature and water content in soil profile probably affect the physiological disorder especially on cool-season turfgrasses in warm and humid weather of Korean summer. The purpose of this research was to analyze the effect of soil temperature and water content on the growth and stress response of creeping bentgrass(Agrostis palustris Huds.) under a humid and warm temperature. USGA(United State of Golf Association) green profile in laboratory test, Daily temperature changes were tested under a dried sand, 70% water content of field capacity, and saturated condition at $34^{\circ}C$ of the USGA green in lab. In this test, the dried sand reached to $80^{\circ}C$, however, the surface temperature decrease of $10^{\circ}C$ on the saturated condition. In the thermal properties test in field, thermal conductivity, thermal diffusivity, and soil temperature were increased followed by irrigation practise. In the water-deficient condition, the highest soil temperature was reached temporally right after irrigation, however, the excessive soil water content higher than field water holding capacity showed the highest soil temperature after a while. This result indicated that a heat damage to root system was caused from the thermal conductivity of a high surface soil temperature. The excessive irrigation when a high turf surface temperature should occur a negative result on tufgrass growth, moreover, it would be fatal to root growth of creeping bentgrass, especially when associated with a poor draining system on USGA sand green. Overall, this study shows that high soil temperature with water-excessive condition negatively affects on cool-season grass during the summer season, suggesting that excessive irrigation, over 70% field capacity of soil condition, does not help to reduce soil temperature for summer season in Korea. In the study that cool-season grass were treated with different water content of soil, The soil had higher temperature and more water holding capacity when treatment rate of soil conditioner was increased. The best growth at the normal water condition and the worst state of growth at thee water-excessive condition were observed.

Stand Structure and Sapling Growth Characteristics of Korean Red Pine Stands Regenerated by the Seed Tree Method (소나무 모수림 시업지의 임분구조 및 치수생육특성)

  • Lee, Daesung;Choi, Jungkee
    • Journal of Korean Society of Forest Science
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    • v.110 no.4
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    • pp.678-688
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    • 2021
  • This study was conducted to provide growth characteristics and stand information in preparation for natural regeneration method and silvicultural treatment of seed tree method in Korean red pine stands by using the field inventoried data 18 years after the seed tree regeneration method in 2001 and analyzing the stand and sapling characteristics. The study area was located in the Research Forest of Kangwon National University, Chuncheon-si, Gangwon-do. In November 2018, we collected tree measurement factors, such as diameter at breast height (DBH), height, crown class, stem quality, tree age, and annual height increment on the established plots. We calculated the basal area, volume, height-diameter ratio (HD ratio), and additional stand density variables such as the relative density and %stocking to analyze the managed stands. The number of mother trees was 58 trees/ha, with a 17.7% stocking level, whereas the number of saplings was 2,330 trees/ha, with a 79.0% stocking level. In germination, the age distribution of saplings ranged from 2001 to 2007, with most belonging to 15-16 years. The development condition of saplings was 10 cm in DBH and 8 m in height. DBH and height were higher as the crown class is more dominant, and this difference was statistically significant in the analysis of variance and Duncan's multiple comparison test (p<0.0001). HD ratio ranged mostly between 80% and 90%, and more than 95% of sapling stems were of high quality, with a straight, unbroken top, non-sweep, and non-diseased stem. On average, the annual height increment of saplings was 21.9 cm at 1 year, 43.3 cm at 5 years, 54.3 cm at 10 years, and 64.3 cm at 15 years. The overall height growth with age increased smoothly. According to the analysis of covariance, the annual height growth by crown class differed significantly. The regression analysis parameters revealed that annual height growth increased with age and dominant crown class.

A Study on Optimization of Nitric Acid Leaching and Roasting Process for Selective Lithium Leaching of Spent Batreries Cell Powder (폐 배터리 셀 분말의 선택적 리튬 침출을 위한 질산염화 공정 최적화 연구)

  • Jung, Yeon Jae;Park, Sung Cheol;Kim, Yong Hwan;Yoo, Bong Young;Lee, Man Seung;Son, Seong Ho
    • Resources Recycling
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    • v.30 no.6
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    • pp.43-52
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    • 2021
  • In this study, the optimal nitration process for selective lithium leaching from powder of a spent battery cell (LiNixCoyMnzO2, LiCoO2) was studied using Taguchi method. The nitration process is a method of selective lithium leaching that involves converting non-lithium nitric compounds into oxides via nitric acid leaching and roasting. The influence of pretreatment temperature, nitric acid concentration, amount of nitric acid, and roasting temperature were evaluated. The signal-to-noise ratio and analysis of variance of the results were determined using L16(44) orthogonal arrays. The findings indicated that the roasting temperature followed by the nitric acid concentration, pretreatment temperature, and amount of nitric acid used had the greatest impact on the lithium leaching ratio. Following detailed experiments, the optimal conditions were found to be 10 h of pretreatment at 700℃ with 2 ml/g of 10 M nitric acid leaching followed by 10 h of roasting at 275℃. Under these conditions, the overall recovery of lithium exceeded 80%. X-ray diffraction (XRD) analysis of the leaching residue in deionized water after roasting of lithium nitrate and other nitrate compounds was performed. This was done to determine the cause of rapid decrease in lithium leaching rate above a roasting temperature of 400℃. The results confirmed that lithium manganese oxide was formed from lithium nitrate and manganese nitrate at these temperatures, and that it did not leach in deionized water. XRD analysis was also used to confirm the recovery of pure LiNO3 from the solution that was leached during the nitration process. This was carried out by evaporating and concentrating the leached solution through solid-liquid separation.

Efficient Conservation and Management of Waterside Parks by Promoting Ecology Awareness of Visitors (이용객 생태 인식 증진을 통한 수변공원의 효율적인 보전 및 관리)

  • Choi, Jong Yun;Kim, Seong-Ki;Kim, Jeong-Cheol;Yun, Hak Jong
    • Korean Journal of Environment and Ecology
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    • v.33 no.2
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    • pp.237-251
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    • 2019
  • This study evaluated the ecological value of waterside parks by investigating the animal distribution and ecological feature in 92 waterside parks and analyzed the change of ecological awareness by users and non-users of waterside parks through ecological education and promotion based on the investigation results. The result confirmed inhabitation of various animals including 9 endangered species (Pernis ptilorhynchus orientalis, Accipiter soloensis, Falco subbuteo, Charadrius placidus, Felis bengalensis euptilura, Lutra lutra, Kaloula borealis, Polyphylla laticollis manchurica, and Leptalina unicolor) in waterside parks. Although waterside parks were constructed to be hydrophilic areas for human use, some of them with high natural characteristics are valued as biological habitat. We investigated user status in 5 areas (Daejeon, Sejong, Cheongju, Kongju, and Buyeo) located at Guem river basin to evaluate people's perception of waterside parks and carried out the ecological education and promotion based on the investigation result. The survey of 200 people showed that there were more users of waterside parks than non-users and that people in their 40's showed the highest use rate. The use frequency of waterside parks located in Daejeon and Cheongju was lower than in other areas (Sejong, Kongju, and Buyeo). We considered it was because Daejeon and Cheongju were urban areas and had relatively more leisure areas such as sports facilities and cafe than other areas, and thus the residents had a lower reliance on waterside parks. Moreover, users used waterside parks more frequently when they were nearer to users' residence. It is because most users perceived waterside parks as the leisure sports facility and thus preferred them to be within walking distance. The users' perception of waterside parks as the ecological space "to be preserved" increased after the ecological education and promotion. The change of the perception was higher among users (80%) than non-users (38%). Therefore, ecological education and promotion were potentially more effective to people who user waterside parks and thus had a higher understanding of the characteristics and specification. In conclusion, 1) although waterside parks were constructed for human use, some parts had high ecological value for the distribution of endangered species and outstanding natural beauty, and 2) it is necessary to change the perception of waterside parks from the hydrophilic attribute to the conservation attribute. Such change of perception would contribute to establishing waterside parks that feature both hydrophilic and conservation attributes in the management or upgrading plan of waterside parks in the future.

Traces of Gwan-a in Yanggeun and Jipyeong in Literature - with the Focus on the History, Scale and Sites of Gwan-a - (문헌으로 찾은 양근·지평 관아의 흔적 - 관아의 연혁·규모·터[址]를 중심으로 -)

  • Yu, Dong-Ho
    • Korean Journal of Heritage: History & Science
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    • v.51 no.1
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    • pp.80-99
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    • 2018
  • In premodern society, the central spaces in local counties were known as Eupchi (邑治), in which Gwan-a (官衙). The Eupchi located in seaside counties were in Eupseong, whereas the Eupchi of inland counties only included a Gwan-a, and did not have a fortress. Yanggeun-gun (楊根郡) and Jipyeonghyeon (砥平縣), which currently form Yangpyeong-gun (楊平郡), were counties where only Gwan-a existed. At present, there are few traces of the Gwan-a in Yanggeun and Jipyeong. In addition, it is impossible to exactly verify the history, scale and location of these two Gwan-as. Therefore, this study attempts to make a rough estimation of the histories, scales and sites of these Gwan-a by analyzing the relevant literature and ancient maps that are scattered according to the principles of spatial organization of local Gwan-a. The Yanggeun and Jipyeong Gwan-a appear to have been built in the early Joseon period. There are three reasons for this assertion: First, in Yanggeun and Jipyeong, Suryeong (守令) were first officially appointed after the early Joseon period. Once Suryoeng were appointed to such counties, the Gwan-a in which they would serve could be established. Second, the Dongheon (東軒) in Yanggengun and the Gaeksa (客舍) in Jipyeonghyeon were rebuilt in 1703 (29th year of the reign of King Sukjong) and 1465 (11th year of the reign of King Sejo), respectively; thus; the Gwan-a must have existed since the early Joseon period.. Third, in Yanggeungun, the Hyanggyo (鄕校) had existed since the early Joseon period, as the Joseon government necessarily established the Hyanggyo in areas where Suryeong were established. The facilities of local Gwan-a in the Joseon period were largely divided into gonghae (公?), educational institutes, and alters. The gonghae was a facility in which the Suryeong and Gwanwon (官員) managed administrative, judicial and military affairs, and consisted of the A-sa (衙舍), Hyeongcheong (鄕廳), Jackcheong (作廳), Gaeksa (客舍), Gungwancheon (軍官廳), and so on. The education institute was called a Hyeonggyo, while alters included the Sajikdan (社稷壇), Seonghwansa (城隍祠) and Yeodan (?壇). Both the Yeongeun and Jipyeong Gwan-a also consisted of such facilities as A-sa, Hyangcheong, Jakcheong, Gaeksa, Gungwancheong, Hyeonggyo, Changgo, Sajikdan, Seonghwangsa, Yeodan, Saryeongcheong, Jiincheong and Gwannocheong. The present sites for both Gwan-as cannot be identified with any certitude. However, they can be roughly identified by connecting the related literatures, oral statements and relics with the principles of spatial organization of local Gwan-a in the Joseon period. ${\bullet}$ Address of the Yanggeun A-sa (Dongheon): the whole of # 15, Gwanmun 1-gil, Yangpyeong-eup (Yanggeun-ri 151) in front of Yanggeun Junior High School at present. ${\bullet}$ Address of Yanggeun Gaeksa: around the Yangpyeong police station at present. ${\bullet}$ Address of Jipyeong A-sa(Dongheon): the whole of Jipyeong-ri 248-250, Jipyeong-myeon at present. ${\bullet}$ Address of Jipyeong Gaeksa: the whole of Jipyeong-ri 238, Jipyeong-myeon at present.

A Study on the Characteristics of Historical Landscape Management Plans for Zhoucun Ancient Mall in Zibo City, Shandong Province, China (중국 산동성 쯔보시 주촌고상성 역사경관관리계획의 특성)

  • Sun, Shu-Zi;Yang, Geon-Seok
    • Journal of the Korean Institute of Traditional Landscape Architecture
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    • v.37 no.2
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    • pp.54-65
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    • 2019
  • China government recently tries to preserve not only the famous national historic-culture cities, but also the small and medium-sized cities due to the damages and destruction of the cities by the rapid economic development, urban expansion and the development of tourism industry. Hence, this study chose 'Zhoucun ancient mall' which is one of the hotness of cultural heritage located in a mid-sized city named 'Zhoucun district Zibo city Shandong province' that has continuously cared historical landscapes by the protective policy regarding the city as a historic-culture resource from '80s, and considered the character of the city's development process on how the historical landscapes were well protected. In fact, the protection policy in Zhoucun ancient mall had been started in early '80s, however, the viable plan was established in 2001 entitled 'Historical block protection planning of Zhoucun Da street'. And then, 'Regulatory plan for the ancient mall site of Zhoucun Da street' established in 2008 has expanded the area of the blocks for protection. However, this plan organized area only block-by-block so that the small blocks couldn't have the unity when expanded. Later in 2015, 'Regulation Organization Plan' hastried to expanded the protect-area to solve the unity problem. As a result of the study, the historical landscape management plan of Zhoucun in Zibo city has been systematically changed in 2001 after. In other words, this 2001's plans established buffer zones for the maintenance of protected areas and the surrounding environment. And then the detailed regulatory plan for 2008 led to a concrete urban management plan. After that, in 2015, it was found that the expansion plan to protect and manage the whole area of Zhoucun disrict is to manage the landscape of the surrounding area including the historical landscape of 'Zhoucun ancient mall'.

Uncertainties of SO2 Vertical Column Density Retrieval from Ground-based Hyper-spectral UV Sensor Based on Direct Sun Measurement Geometry (지상관측 기반 태양 직달광 관측장비의 초분광 자외센서로부터 이산화황 연직칼럼농도의 불확실성 분석 연구)

  • Kang, Hyeongwoo;Park, Junsung;Yang, Jiwon;Choi, Wonei;Kim, Daewon;Lee, Hanlim
    • Korean Journal of Remote Sensing
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    • v.35 no.2
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    • pp.289-298
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    • 2019
  • In this present study, the effects of Signal to Noise Ratio (SNR), Full Width Half Maximum (FWHM), Aerosol Optical Depth (AOD), $O_3$ Vertical Column Density ($O_3$ VCD), and Solar Zenith Angle (SZA) on the accuracy of sulfur dioxide Vertical Column Density ($SO_2$ VCD) retrieval have been quantified using the Differential Optical Absorption Spectroscopy (DOAS) method with the ground-based direct-sun synthetic radiances. The synthetic radiances produced based on the Beer-Lambert-Bouguer law without consideration of the diffuse effect. In the SNR condition of 650 (1300) with FWHM = 0.6 nm, AOD = 0.2, $O_3$ VCD = 300 DU, and $SZA=30^{\circ}$, the Absolute Percentage Difference (APD) between the true $SO_2$ VCD values and those retrieved ranges from 80% (28%) to 16% (5%) for the $SO_2$ VCD of $8.1{\times}10^{15}$ and $2.7{\times}10^{16}molecules\;cm^{-2}$, respectively. For an FWHM of 0.2 nm (1.0 nm) with the $SO_2$ VCD values equal to or greater than $2.7{\times}10^{16}molecules\;cm^{-2}$, the APD ranges from 6.4% (29%) to 6.2% (10%). Additionally, when FWHM, SZA, AOD, and $O_3$ VCD values increase, APDs tend to be large. On the other hand, SNR values increase, APDs are found to decrease. Eventually, it is revealed that the effects of FWHM and SZA on $SO_2$ VCD retrieval accuracy are larger than those of $O_3$ VCD and AOD. The SZA effects on the reduction of $SO_2$ VCD retrieval accuracy is found to be dominant over the that of FWHM for the condition of $SO_2$ VCD larger than $2.7{\times}10^{16}molecules\;cm^{-2}$.

A Historical and Archaeological Study on Gabong Taesil of King Dangjong in Joseon (조선 단종의 가봉태실에 대한 문헌·고고학적 검토)

  • Shim, Hyun Yong
    • Korean Journal of Heritage: History & Science
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    • v.45 no.3
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    • pp.80-99
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    • 2012
  • It is known that there are two Gabong taesil (shrine for King's umbilical cord) of King Danjong, the 6th king of Joseon, remaining today. One of them is Mt. Sogok in Sacheon-city, Gyeongsangnam-do and the other is Mt. Beomnim in Seongju-gun, Gyeongsangbuk-do. The academic sector argued about this matter as there cannot be two Gabong taesil for one king. I once argued that Taesil on Mt. Beomnim in Seongju is King Danjong's Gabong taesil and Danjong taesil in Sacheon is the one for Prince Inseongdaegun, the eldest son of King Yejong. At that time, however, I had not examined the archaeological relics found in these places. In result of making an archaeological approach, I have come to the following conclusions :1. King Danjong had two Taesil : Agi taesil(shrine for baby's umbilical cord) and Gabong taesil. The first Agi taesil was created on Taebong of Mt. Seonseok in Seongju on November 26, 1441, but was moved to Mt. Beomnim in Seongju in 1451 to form the second Agi taesil. In 1458, King Sejo eliminated his Taesil. The stone structures of Gabong taesil still remains on Taebong of Mt. Beomnim, so it has been assumed that King Danjong established them during his reign (1452-1455). 2. Taesil in Sacheon has been known as King Danjong's Taesil because of King Danjong's reinstatement during the reign of King Sukjong. His Taesil was repaired with the reinstatement and King Sukjong was mistaken that Taesil in Sacheon was King Danjong's Taesil to fix it. The time of restoration has been assumed to be soon after the restoration of King Danjong's tomb (1699-1719). Taesil is missing the book of records and rails around the stone structure because the tombs of reinstated kings were restored without rails. 3. It is incorrect that Taesil in Sacheon was known as King Danjong's Taesil, It has been concluded that this Taesil was for Prince Inseongdaegun who was born in 1462. I focused on the fact that Prince Inseongdaegun's Taesil was in Seosamneung Taesil instead of King Danjong's Taesil. When Yiwangjik stored King Danjong's Taesil in Seoul in 1928 and moved it to Seosamneung in 1930, he found that the epitaph on the tombstone recorded that it was Prince Inseongdaegun, not King Danjong, and created Prince Inseongdaegun's Taesil in Seosamneung. I referred to "Taebong", which was created when Seosamneung Taesil was built during the Japanese imperial rule over Joseon, and the relics found in Taesil in Sacheon and Seosamneung.

Growth Conditions and Maintenance of Natural Monument Old Big Trees in Gangwondo (강원도 내 천연기념물 노거수의 생육환경 및 관리현황)

  • Heo, Bok Soo;Kim, Hyo Jeong;Lee, Won Ho;Kang, Hee Jin
    • Korean Journal of Heritage: History & Science
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    • v.44 no.1
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    • pp.182-195
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    • 2011
  • Old big tree transcends the simple meaning of trees as they are the natural monuments that embody the people's history and culture of this land. The Cultural Heritage Administration of Korea (CHA) defines and protects old big tree based not only on the size of the tree but also on its definitive cultural and natural factors such as value, implications, and originality. This research aims to identify and analyze the habitation and measurements, the soil conditions, as well as the protective facilities of 14 old big tree spread throughout the Gangwondo. The research examined the soundness of the arboreal form, the degree of damage on the bark, as well as the quantity of leafs levels to evaluate the overall condition of growth and development. Then, the tree height, the eastwest and south-north width of the crown, the sternum circumference, and the root circumference were recorded to identify the measurements of the selected old big tree. Also, the research analyzed 9 elements such as soil texture, pH levels, and organic contents in order to determine the scientific characteristics of soil upon which the trees draw nutrition. Finally, the research evaluated supporting pillars, lightning rods, iron pulling-facilities, as well as notice boards to study the protective facilities of old big tree. The research procedures revealed that 78.57% of the old big tree identified as natural monuments in the Gangwondo have average to above average habitation conditions. Also, the average tree height reaches 18.80m above ground while the average root circumference measures 7.34m. Moreover, the results of the scientific analyses conducted on the soil elements determined that most chemical values were within the defined levels, with the exception of phosphoric acid levels falling within the hyper-nutritious range. Finally, although most of the protective facilities did support the habitation of the Old big tree, there were some supporting pillars and iron pulling-facilities that actually damaged the trees. This research means to provide foundational reference data for the analysis of the habitation and management conditions of natural monument old big tree within the Gangwondo. A follow-up topic led by the results of this research is the identification and analysis of correlating environmental elements that affect the habitation of the old big tree.

Ecological Characteristics and Changes of Quercus mongolica Community in Namsan (Mt.), Seoul (서울시 남산 신갈나무림 생태계 특성과 변화 연구)

  • Han, Bong-Ho;Park, Seok-Cheol;Kim, Jong-Yup;Kwak, Jeong-In
    • Journal of the Korean Institute of Landscape Architecture
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    • v.50 no.2
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    • pp.41-63
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    • 2022
  • The purpose of this study is to secure objective and precise data through ecosystem monitoring, to reveal ecological characteristics through comparison and analysis with past survey data, and to accumulate basic data for diagnosing the current situation and predicting changes in the ecosystem. The target site is the 'Quercus mongolica forest on the Buksa-myeon of Namsan', which was designated as an Ecological Landscape Conservation Area (ELCA) of Seoul in July 2006. The research contents are analysis of soil environment change (1986~2016), change of actual vegetation (1978~2016), and change of plant community structure (1994~2016). A total of 8 fixed surveys (400~1,200m2) were established in 1994 and 2000. Analysis items are importance value, species and population, and Shannon's species diversity. The soil environment of Namsan is acidic (pH 4.40 in 2016), which is expected to have a negative impact on tree growth and vegetation structure due to its low capacity for exchangeable cations. Quercus mongolica forest in Namsan is mainly distributed on the northern slopes. The actual vegetation area changed from 49.4% in 1978 → 80.7% in 1986 → 82.4% in 2000 → 88.3% in 2005 → 88.3% in 2009 → 70.3% in 2016. In 2016, the forest decreased by 18% compared to 2009. While there was increased growth of Quercus mongolica in the tree layer from 2009 to 2016, the overall decline in vegetation area was due to logging and fumigation management following the spread of oak wilt in 2012. As for the changes in the plant community structure, Quercus mongolica of the tree layer was damaged by oak wilt, and the potential vegetation that can form the next generation was ambiguous. In the subtree layer, the force of urbanization tree species such as Styrax japonicus, Sorbus alnifolia, and Acer palmatum. was maintained or increased. In the shrub layer, the number of trees and species increased significantly due to the open tree crown, and accordingly, the species diversity of Shannon for woody plants also increased. In Quercus mongolica forest of Namsan, various ecological changes are occurring due to the effects of urban environments such as air pollution and acid rain, the limitation of Quercus mongolica pure forest due to oak wilt, and the introduction of exotic species, thus, it is necessary to establish a management plan through continuous monitoring.