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Long-term changes in radial growth of seven tree species in the mixed broadleaf-Korean pine forest in Northeast China:Are deciduous trees favored by climate change?
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作者 Xiufang Gong Danyang Yuan +2 位作者 Liangjun Zhu Zongshan Li Xiaochun Wang 《Journal of Forestry Research》 SCIE EI CAS CSCD 2024年第5期63-77,共15页
The role of the temperate mixed broadleaf-Korean pine forest(BKF)in global biogeochemical cycles will depend on how the tree species community responds to climate;however,species-specific responses and vulner-abilitie... The role of the temperate mixed broadleaf-Korean pine forest(BKF)in global biogeochemical cycles will depend on how the tree species community responds to climate;however,species-specific responses and vulner-abilities of common trees in BKF to extreme climates are poorly understood.Here we used dendrochronological meth-ods to assess radial growth of seven main tree species(Pinus koraiensis,Picea jezoensis,Abies nephrolepis,Fraxinus mandshurica,Phellodendron amurense,Quercus mongolica,and Ulmus davidiana)in an old-growth BKF in response to climate changes in the Xiaoxing’an Mountains and to improve predictions of changes in the tree species compo-sition.Temperature in most months and winter precipita-tion significantly negatively affected growth of P.jezoensis and A.nephrolepis,but positively impacted growth of P.koraiensis and the broadleaf species,especially F.mandshu-rica and U.davidiana.Precipitation and relative humidity in June significantly positively impacted the growth of most tree species.The positive effect of the temperature during the previous non-growing season(PNG)on growth of F.mandshurica and Q.mongolica strengthened significantly with rapid warming around 1981,while the impact of PNG temperature on the growth of P.jezoensis and A.nephrolepis changed from significantly negative to weakly negative or positive at this time.The negative response of radial growth of P.jezoensis and A.nephrolepis to precipitation during the growing season gradually weakened,and the negative response to PNG precipitation was enhanced.Among the studied species,P.koraiensis was the most resistant to drought,and U.davidiana recovered the best after extreme drought.Ulmus davidiana,P.jezoensis and A.nephrolepis were more resistant to extreme cold than the other species.Climate warming generally exacerbated the opposite growth patterns of conifer(decline)and broadleaf(increase)spe-cies.Deciduous broadleaf tree species in the old-growth BKF probably will gradually become dominant as warming continues.Species-specific growth-climate relationships should be considered in future models of biogeochemical cycles and in forestry management practices. 展开更多
关键词 Tree rings Extreme climate Resistance and recovery Broad-leaved and korean pine mixed forest
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Group Images of Korean Women on Douyin:Representation,Generation,and Identification
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作者 JIN Yihan CHEN Lu 《Cultural and Religious Studies》 2024年第2期95-103,共9页
Since 2023,the slogan“Question Korean women,understand Korean women,learn Korean women”has become popular in Chinese social networks.Previously,Chinese netizens have not paid such attention to women from other count... Since 2023,the slogan“Question Korean women,understand Korean women,learn Korean women”has become popular in Chinese social networks.Previously,Chinese netizens have not paid such attention to women from other countries.In response to this phenomenon,this paper combines neoliberal feminist theories with thematic analysis to obtain a total of 80 valid samples from the Douyin platform to analyze the image of Korean women disseminated on the Douyin platform.Finally,it is concluded that the image of Korean women’s strict self-discipline,internal and external cultivation,sobriety of thought,and the spirit of courageous struggle have to a certain extent promoted the awakening of self-consciousness of female netizens in China;on the other hand,it is also necessary to realize that the image of Korean women disseminated in Douyin is not completely true,and it is also necessary to be alert to the phenomenon that the gender dichotomy has been reduced to the attraction of network traffic and capital as a sharp weapon. 展开更多
关键词 Douyin korean women FEMINISM group images
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Application of Color Psychology in Korean Brand Identity Design-Etude House
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作者 Jingyao Luo Choi Albort Young 《Cultural and Religious Studies》 2024年第1期24-31,共8页
The purpose of this analysis is to delve into the application of color psychology in the logo design of Korean cosmetic brands,using Etude House as an example for an exhaustive analysis.By examining the history of the... The purpose of this analysis is to delve into the application of color psychology in the logo design of Korean cosmetic brands,using Etude House as an example for an exhaustive analysis.By examining the history of the Etude House brand,the evolution of the logo design,and the changes in color choices,we analyze the traditional concepts of color symbolism in Korean culture and the culture of color in contemporary society in order to reveal the important role of color in cosmetic brand image.Through an in-depth analysis of the use of color in Etude House’s brand identity,we further analyze the impact of color on consumer emotions and purchasing behavior,as well as the potential impact of brand identity changes on market performance.Finally,the conclusions of the analysis summarize the practical application of color psychology in Etude House’s brand logo design,suggest recommendations for other Korean cosmetic brands to draw upon in their logo design,and discuss future directions. 展开更多
关键词 color psychology brand identity design Etude House korean cosmetics consumer emotions market performance
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Analyzing the Essay Writing Patterns of Iranian Intermediate-Level Korean Language Learners: A Study Based on the TOPIK Exam
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作者 Vahid Reza Nasrollahi 《Sino-US English Teaching》 2024年第8期354-371,共18页
This study examines the writing abilities of Iranian intermediate Korean learners,specifically their performance in the compositional writing section of the Test of Proficiency in Korean(TOPIK).By utilizing the many F... This study examines the writing abilities of Iranian intermediate Korean learners,specifically their performance in the compositional writing section of the Test of Proficiency in Korean(TOPIK).By utilizing the many FACETS-Rasch Model,we meticulously analyzed nine writing samples from the 52nd TOPIK.These samples were evaluated using a modified rubric ranging from 0 to 3 based on predefined criteria for written composition.The results underscored that the sections on“appropriateness of spacing and spelling,”“relevance of vocabulary,”and“content diversity”presented the most significant challenges for the learners.On the other hand,“the quantity of writing”emerged as the least challenging aspect.These findings reveal substantial disparities in various aspects of writing proficiency among learners.The study not only pinpoints issue areas in writing skills,but also underscores the necessity of customized teaching strategies within the TOPIK framework to address these weaknesses.Consequently,it offers valuable insights that could bolster the effectiveness of teaching writing to Korean language learners.The findings of this study are not only significant for the field of language education,but also contribute to a deeper understanding of the challenges faced by intermediate learners and provide a roadmap for improving language instruction. 展开更多
关键词 TOPIK writing evaluation Iranian intermediate korean learners multinational research analysis writing challenges language education strategies
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PP-GAN:Style Transfer from Korean Portraits to ID Photos Using Landmark Extractor with GAN 被引量:1
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作者 Jongwook Si Sungyoung Kim 《Computers, Materials & Continua》 SCIE EI 2023年第12期3119-3138,共20页
The objective of style transfer is to maintain the content of an image while transferring the style of another image.However,conventional methods face challenges in preserving facial features,especially in Korean port... The objective of style transfer is to maintain the content of an image while transferring the style of another image.However,conventional methods face challenges in preserving facial features,especially in Korean portraits where elements like the“Gat”(a traditional Korean hat)are prevalent.This paper proposes a deep learning network designed to perform style transfer that includes the“Gat”while preserving the identity of the face.Unlike traditional style transfer techniques,the proposed method aims to preserve the texture,attire,and the“Gat”in the style image by employing image sharpening and face landmark,with the GAN.The color,texture,and intensity were extracted differently based on the characteristics of each block and layer of the pre-trained VGG-16,and only the necessary elements during training were preserved using a facial landmark mask.The head area was presented using the eyebrow area to transfer the“Gat”.Furthermore,the identity of the face was retained,and style correlation was considered based on the Gram matrix.To evaluate performance,we introduced a metric using PSNR and SSIM,with an emphasis on median values through new weightings for style transfer in Korean portraits.Additionally,we have conducted a survey that evaluated the content,style,and naturalness of the transferred results,and based on the assessment,we can confidently conclude that our method to maintain the integrity of content surpasses the previous research.Our approach,enriched by landmarks preservation and diverse loss functions,including those related to“Gat”,outperformed previous researches in facial identity preservation. 展开更多
关键词 Style transfer style synthesis generative adversarial network(GAN) landmark extractor ID photos korean portrait
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Information Extraction Based on Multi-turn Question Answering for Analyzing Korean Research Trends
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作者 Seongung Jo Heung-Seon Oh +2 位作者 Sanghun Im Gibaeg Kim Seonho Kim 《Computers, Materials & Continua》 SCIE EI 2023年第2期2967-2980,共14页
Analyzing Research and Development(R&D)trends is important because it can influence future decisions regarding R&D direction.In typical trend analysis,topic or technology taxonomies are employed to compute the... Analyzing Research and Development(R&D)trends is important because it can influence future decisions regarding R&D direction.In typical trend analysis,topic or technology taxonomies are employed to compute the popularities of the topics or codes over time.Although it is simple and effective,the taxonomies are difficult to manage because new technologies are introduced rapidly.Therefore,recent studies exploit deep learning to extract pre-defined targets such as problems and solutions.Based on the recent advances in question answering(QA)using deep learning,we adopt a multi-turn QA model to extract problems and solutions from Korean R&D reports.With the previous research,we use the reports directly and analyze the difficulties in handling them using QA style on Information Extraction(IE)for sentence-level benchmark dataset.After investigating the characteristics of Korean R&D,we propose a model to deal with multiple and repeated appearances of targets in the reports.Accordingly,we propose a model that includes an algorithm with two novel modules and a prompt.A newly proposed methodology focuses on reformulating a question without a static template or pre-defined knowledge.We show the effectiveness of the proposed model using a Korean R&D report dataset that we constructed and presented an in-depth analysis of the benefits of the multi-turn QA model. 展开更多
关键词 Natural language processing information extraction question answering multi-turn korean research trends
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Extension of Goal-Directed Behavior Model for Post-Pandemic Korean Travel Intentions to Alternative Local Destinations: Perceived Risk and Knowledge
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作者 Heesup Han Hong Ngoc Nguyen +1 位作者 Hyerin Lee Sanghyeop Lee 《International Journal of Mental Health Promotion》 2023年第4期449-469,共21页
Since the outbreak of COVID-19,tourists have been increasingly concerned over various risks of international travel,while knowledge of the pandemic appears to vary significantly.In addition,as travel restrictions cont... Since the outbreak of COVID-19,tourists have been increasingly concerned over various risks of international travel,while knowledge of the pandemic appears to vary significantly.In addition,as travel restrictions continue to impact adversely on international tourism,tourism efforts should be placed more on the domestic markets.Via structural equation modeling,this study unearthed different risk factors impacting Korean travelers’choices of alternative local destinations in the post-pandemic era.In addition,this study extended the goal-directed behavior framework with the acquisition of perceived risk and knowledge of COVID-19,which was proven to hold a sig-nificantly superior explanatory power of tourists’decisions of local alternatives over foreign countries during the COVID-19 pandemic.Furthermore,desire was found to play an imminent mediating role in the conceptual mod-el,maximizing the impact of perceived risk on travel intentions.Henceforth,this research offers meaningful the-oretical implication as thefirst empirical study to deepen the goal-directed behaviour framework with perceived risk and knowledge in the context of post-COVID-19 era.It also serves as insightful knowledge for Korean tour-ism authorities and practitioners to understand local tourists’decision-making processes and tailor effective recovery strategy for domestic tourism. 展开更多
关键词 Travel intention goal-directed behavior desire perceived risk COVID-19 domestic tourism korean tourists
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New Year,New Insights:Interpreting the Cultural Nuances of Nowruz and Seollal for Iranian Students Learning Korean
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作者 Vahid Reza Nasrollahi 《Sino-US English Teaching》 2023年第11期430-438,共9页
With proper education,students would be better equipped for life in a more diverse and globally integrated world.To foster intercultural conversation and global citizenship among students,various cultural practices sh... With proper education,students would be better equipped for life in a more diverse and globally integrated world.To foster intercultural conversation and global citizenship among students,various cultural practices should be brought to their attention,and they should be encouraged to develop respect for these traditions.This study compares the cultural significance,rites,and customs,traditional meals,social interactions,and symbolism of the Iranian New Year(Nowruz;نوروز)with those of the Korean New Year(Seollal;설날)to determine whether or not Iranian students could benefit from learning Korean in terms of language acquisition,cultural understanding,and celebratory behavior.The findings shed light on the importance of instituting policies that foster intercultural conversation and including cross-cultural studies in educational programs.Some recommendations include increasing access to multicultural education,teaching languages,sponsoring international and intercultural activities,developing an appreciation of diverse cultures,and educating instructors. 展开更多
关键词 New Year celebration Nowruz Seollal Iranian students korean language
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From People as Foundation(Minbon)to Concept of a Republic(Minkuk):Tracing Neo-Confucianism in Korean History
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作者 Yi Tae-jin 《Cultural and Religious Studies》 2023年第3期105-117,共13页
This article is the memoirs of the author’s long-time research on the Neo-Confucian history of the Chosun dynasty Korea.The author recalled his academic achievement of the several stages of the historical changes of ... This article is the memoirs of the author’s long-time research on the Neo-Confucian history of the Chosun dynasty Korea.The author recalled his academic achievement of the several stages of the historical changes of Korean society with the Neo-Confucianism.The time range covered from the late 14th century to the nineteenth century.The research position was adhered to the view of the positive function of Confucianism which aimed to overcome the negative understanding highly influenced by the Japanese colonialism.He examined the socio-economic development accompanied with the Neo-Confucianism at the first stage.In the part of the sixteenth century the formation of Sarim group was interpreted as critical forces and the prevailed factionalism as the principle of politics rather than the chronic political strife.The author introduced his unique achievement that the ideology of the Neo-Confucianism had been strongly intensified with the response to the long term natural catastrophes of the Little Ice Age(c.1490-1760).The republican concept of 18th-century impartial rulers,the most important achievement of Korean Neo-Confucianism,was viewed as the result of effort to overcome the natural disasters.This topic was connected to the concept of republic which shows in a diagram of the Korean national flag. 展开更多
关键词 Chiangnan Agriculture Long Term Natural catastrophes Concept of Republic korean National Flag
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Reform of the Teaching Model of Korean Intensive Reading Courses in Vocational High Schools in the Era of All-Media
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作者 Ruoxuan Chen 《Journal of Contemporary Educational Research》 2023年第11期17-23,共7页
The use of multimedia technology in the teaching process is the current mainstream trend in teaching development.The arrival of the all-media era is not only a huge challenge to the traditional teaching model,but also... The use of multimedia technology in the teaching process is the current mainstream trend in teaching development.The arrival of the all-media era is not only a huge challenge to the traditional teaching model,but also a huge opportunity for the reform of the teaching model.Combining traditional education models with modern scientific and technological means,and learning from each other’s strengths can stimulate students’subjective initiative in learning.On the other hand,it is also an important way for teachers to improve their teaching abilities.This article analyzes the opportunities brought by the all-media era to the reform of education models based on the teaching status and teaching difficulties of Korean intensive reading courses in vocational high schools,and proposes a teaching model reform strategy for Korean intensive reading courses in vocational high schools in the all-media era. 展开更多
关键词 All-media era Teaching model reform Vocational high school teaching korean teaching
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The Reform Process of English Medium Instruction in Korean Higher Education
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作者 Ping Yu Na Yao Lili Cheng 《Journal of Contemporary Educational Research》 2023年第11期84-89,共6页
In the context of the internationalization of higher education,many non-English speaking countries,from Europe to Asia,are promoting English as a medium of instruction(EMI).The EMI in South Korea started earlier and d... In the context of the internationalization of higher education,many non-English speaking countries,from Europe to Asia,are promoting English as a medium of instruction(EMI).The EMI in South Korea started earlier and developed rapidly under the promotion.From the initial“Study Abroad in Korea Plan”to the World Class University(WCU)and Brain Korea 21st century(BK21)PLUS programs,with the support and guidance of the government,South Korea’s higher education has made significant progress,with the global top 100 universities in QS increasing from 1 to 6 in South Korea. 展开更多
关键词 English medium instruction EMI Internationalization of education korean higher education
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Visual Nationalism and Communal Rituals:Park Saengkwang’s Art and Korean Shamanism
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作者 Seojeong Shin 《Cultural and Religious Studies》 2022年第12期663-681,共19页
This paper analyzes Park Saengkwang(1904-1985)’s artwork,created in the 1980s and influenced by Musok,Korean Shamanism.It explores Musok’s thematic significance in the development of his distinctive style and the in... This paper analyzes Park Saengkwang(1904-1985)’s artwork,created in the 1980s and influenced by Musok,Korean Shamanism.It explores Musok’s thematic significance in the development of his distinctive style and the inspiration behind his stylistic changes.Park’s ink paintings are done in bold and intense colors and create an intriguing,mysterious mood,inviting the viewers to the primordial visual experience and exposing its viewers to Korean Shamanism,which has endured the perception that fluctuated between positive and negative throughout Korean history.The practice became a fitting cultural emblem associated with the national identity during the 1970s and 1980s,and thus became a way for Park to explicitly articulate his cultural roots,creating a visual connotation of“Korean.”His art,portraying gut,Korean shamanistic communal rituals,could be conceived as a pictorial rendering of the idea of kibok,praying for good fortune,and served as a pujŏk,talisman paper,that possesses magical healing and protecting power.By striving to overcome the stylistic conflicts between Korean and Japanese,or traditional and Western,Park’s art accomplished the visual rhetoric of national aesthetic sensitivity that built on the communal thoughts and cultural experience of shamanism in the modern history of Korea. 展开更多
关键词 Park Saengkwang korean colored ink painting korean Shamanism Twentieth Century korean Art korean art and shamanism identity visual nationalism communal thoughts and rituals
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Influence of canopy on precipitation and its nutrient elements in broadleaved/Korean pine forest on the northern slope of Changbai Mountain 被引量:3
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作者 肖以华 代力民 +3 位作者 牛德奎 佟富春 陈高 邓红兵 《Journal of Forestry Research》 SCIE CAS CSCD 2002年第3期201-204,251,共4页
The precipitation distribution quantity of canopy in broadleaved/Korean pine forest was measured during the growing season (Jun.–Sept.) in 2001 in the Changbai Mountain, Jilin Province, P. R. China. Results indicated... The precipitation distribution quantity of canopy in broadleaved/Korean pine forest was measured during the growing season (Jun.–Sept.) in 2001 in the Changbai Mountain, Jilin Province, P. R. China. Results indicated that the amounts of stemflow, throughfall, and interception were 37.39, 322.12 and 109.69 mm, accounting for 7.97%, 68.65% and 23.38% of the total rainfall, respectively. The rate of stemflow was higher in Jul. and Aug. than other months. The rate of throughfall dropped off from Jun. to Sept., however, rate of interception changed contrarily from 19.43% to 31.02% during the growing season. According to our analysis, the concentration of nutrient elements were arranged as Ca>Mg>N>K>Fe>P>Cu>Mn for rainfall, K>N>Mg>Ca>P>Fe>Mn>Cu for throughfall, and Mn>P>K>Cu>Fe>N>Mg>Ca for being leached through canopy. Nutrients concentration in stewflow and throughfall changed significantly when rainfall passed canopy, and concentration of all elements increased except for Ca and Mg. 展开更多
关键词 Broadleaved/korean pine forest Precipitation distribution Concentration Nutrient elements CANOPY STEMFLOW THROUGHFALL INTERCEPTION
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Functional evaluation for effective compositions in seed oil of Korean pine 被引量:11
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作者 王振宇 陈小强 《Journal of Forestry Research》 SCIE CAS CSCD 2004年第3期215-217,共3页
The effect of seed oil of Korean pine (Pinus koraiensis) on the rats' blood-fat and its anti-ageing function was stud-ied for appraising the efficacy of the seed oil of Korean pine. Sixty experimental rats were ra... The effect of seed oil of Korean pine (Pinus koraiensis) on the rats' blood-fat and its anti-ageing function was stud-ied for appraising the efficacy of the seed oil of Korean pine. Sixty experimental rats were randomly divided into 5 groups (half males and half females in each group) as normal control group, high fat diet control group, and three groups (Group 1 Group 2, Group 3) that were fed with feedstuff with the contents of the seed oil of 2.0g/(kgd-1), 4.0g/(kgd-1) and 8.0g/(kgd-1), respec-tively. The indexes such as superoxide dismutase (SOD), glutathione peroxidase (GSH-PX) and anti-oxidation capacity (AOC) were measured by Reagent Kit method. It was found that the seed oil of the Korean pine could reduce the content of triglyc-eride and improve SOD as well as GSH-PX activity in serum. These indexes of the rats in Group 2 fed with Korean pine seed oil of 4.0 g/(kgd-1) reached the significant level and those of rats in Group 3 fed with the seed oil of 8.0 g/(kgd-1) reached the extremely significant level. The results indicated the seed oil of Korean pine had function of regulating the level of blood-fat and anti-ageing. 展开更多
关键词 korean pine seed oil Effective compositions Functional evaluation Blood-fat ANTI-AGEING
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Storage dynamics of fallen trees in a mixed broadleaved and Korean pine forest 被引量:3
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作者 代力民 陈高 +3 位作者 邓红兵 徐振邦 李扬 陈华 《Journal of Forestry Research》 SCIE CAS CSCD 2002年第2期107-110,共4页
A study of the storage dynamics in the mixed broadleaved and Korean pine forests was carried out in the Changbai Mountains, Jilin Province, P. R. China. The modifying law of fallen trees was the storage dynamics of th... A study of the storage dynamics in the mixed broadleaved and Korean pine forests was carried out in the Changbai Mountains, Jilin Province, P. R. China. The modifying law of fallen trees was the storage dynamics of the existing fallen trees and the annual input in the mixed broadleaved and Korean pine forest. The current storage of fallen trees was 16.25 t昲m-2 in the initially, but after 100 years, 85% of the storage in dry weight was decomposed, and little material was left after 300 years. The average annual input of fallen trees was 0.6 t昲m-2and it increased with time to 31.0 t昲m-2after 200 years, which was maintained until the climax community ended. The total storage of fallen trees increased in the early stage. The decomposition of fallen trees eventually reached equilibrium with storage being identical with the annual input of fallen trees. 展开更多
关键词 Broadleaved/korean pine forest STORAGE DYNAMICS Fallen trees Changbai Mountains.
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Dynamics of profiles and storage of carbon dioxide in broadleaved/Korean forest in Changbai Mountain 被引量:2
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作者 韩士杰 林丽莎 +4 位作者 于贵瑞 张军辉 吴家兵 赵晓松 关德新 《Journal of Forestry Research》 SCIE CAS CSCD 2003年第4期275-279,共5页
CO2 concentrations at different heights in a broadleaved/Korean forest (with a mean height of 26 m) were measured with infrared gas analyzer IRGA (model 2250D, LI-COR Inc. and LI-COR, 820) from Aug. to Oct. of 1999, A... CO2 concentrations at different heights in a broadleaved/Korean forest (with a mean height of 26 m) were measured with infrared gas analyzer IRGA (model 2250D, LI-COR Inc. and LI-COR, 820) from Aug. to Oct. of 1999, Apr. to Jul. of 2000, and from Aug. 2002 to Sept. 2003. Based on the collected dada, the diurnal and seasonal dynamics of profiles and storage of carbon dioxide in the forest were analyzed. The diurnal CO2 profiles showed that the vertical distribution of CO2 concentration were different for daytime and nighttime, and the CO2 concentration was highest close to forest floor, no matter at daytime and nighttime. The seasonal profiles of CO2 showed that stratification in the canopy was evident during growth season. CO2 concentrations at different heights (60 m to 2.5 m) had a little change in March, with a difference of 10 mmolmol-1, but had a significant change in July, with a difference of 60 mmolmol-1. In July, there also existed a greater gradient of CO2 concentrations at canopy (22, 26 and 32 m), with a difference of 8 mmolmol-1. The calculated total storage (ΔC/Δt ) of CO2 in the air column with height of 40 m beneath eddy covariance instrument was negative, and made a little contribution to NEE. 展开更多
关键词 CO2 concentration CO2 profile CO2 storage Broadleaved/korean pine forest Vertical distribution Concentration gradient
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Soil carbon dioxide fluxes of a typical broad-leaved/Korean pine mixed forest in Changbai Mountain, China 被引量:3
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作者 王琛瑞 吴劼 +1 位作者 梁战备 黄国宏 《Journal of Forestry Research》 SCIE CAS CSCD 2004年第4期268-272,共5页
The forest ecosystem plays an important role in the global carbon cycling. A study was conducted to evaluate soil CO2 flux and its seasonal and diurnal variation with the air and soil temperatures by using static clos... The forest ecosystem plays an important role in the global carbon cycling. A study was conducted to evaluate soil CO2 flux and its seasonal and diurnal variation with the air and soil temperatures by using static closed chamber technique in a typical broad-leaved/Korean pine mixed forest area on the northern slope of Changbai Mountain, Jilin Province, China. The experiment was carried out through the day and night in the growing season (from June to September) in situ and sample gas was analyzed by a gas chromatograph. Results showed that the forest floor was a large net source of carbon, and soil CO2 fluxes had an obvi-ous law of seasonal and diel variation. The soil CO2 flux of broad-leaved/Korean pine mixed forest was in the range of 0.302.42 mmol穖-2穝-1 with the mean value of 0.98 mmol穖-2穝-1. An examination on the seasonal pattern of soil CO2 emission suggested that the variability in soil CO2 flux could be correlated with variations in soil temperature, and the maximum of mean CO2 flux occurred in July ((1.27±23%) mmol穖-2穝-1) and the minimum was in September ((0.50±28%) mmol穖-2穝-1). The fluctuations in diel soil CO2 flux were also correlated with changes in soil temperature; however, there existed a factor for a time lag. Soil CO2 flux from the forest floor was strongly related to soil temperature and had the highest correlation with temperature at 6-cm depth of soil. Q10 values based on air temperature and soil temperature of different soil depths were at the ranges of 2.09–3.40. 展开更多
关键词 Soil CO2 flux Broad-leaved/korean pine mixed forest Q10 value Changbai Mountain
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A preliminary study on in-stream large woody debris in broadleaved and Korean pine forest in Changbai Mountain, Northeast China 被引量:2
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作者 邓红兵 王青春 王庆礼 《Journal of Forestry Research》 SCIE CAS CSCD 2002年第3期196-200,251,共5页
This study was conducted in Erdaobaihe River passing through the broadleaved and Korean pine forest located on the north slope of Changbai Mountain. In-stream large woody debris (LWD) in two segments of the river chan... This study was conducted in Erdaobaihe River passing through the broadleaved and Korean pine forest located on the north slope of Changbai Mountain. In-stream large woody debris (LWD) in two segments of the river channel was investigated with base diameter, top diameter, length, and decay class. To study relationship between in-stream LWD and adjacent riparian forest, species of each log of LWD in segment 1 was identified, and the riparian forest was examined by setting a 32m?4 m quadrat consisting of twelve 8m?m small quadrats. The results showed that, in segment 1, in-stream LWD loading was 1.733 m3/100m or 10.83 m3hm-2, and in segment 2, it was 1.709m3/100m or 21.36 m3hm-2. In-stream LWD in decay class III and IV were accounted for a high proportion, which was different from that in the broadleaved and Korean pine forest, and the possible reason might be different decomposing velocities due to different decomposing conditions. Logs of LWD in stream and living trees in riparian forest declined as diameter increased, and it was in a reverse J-shaped distribution except logs of LWD in segment 1 in the first diameter class. Volumes of LWD in stream and living trees in riparian forest increased as diameter increased, and it was in a typical J-shaped distribution. Loading and species component of in-stream LWD were correlative to status of riparian forest to a certain extent, and there also existed difference. Comparing the correlation and difference was helpful to study on dynamic of the riparian forest. 展开更多
关键词 In-stream large woody debris Broadleaved and korean pine forest Changbai Mountain LOADING Riparian zone
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Effect of soil moisture gradient on structure of broad-leaved/Korean pine forest in Changbai Mountain 被引量:1
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作者 王艳 王庆礼 +3 位作者 代力民 王淼 周莉 代保清 《Journal of Forestry Research》 SCIE CAS CSCD 2004年第2期119-123,i002,共6页
A 112 m×8 m sample pot which includes 14 sub-plots was set up along the slope in Hongshi Forestry Farm of Baihe Forestry Bureau (127°55′E, 42°30′ N), Jilin Province in August 2002. Community structure... A 112 m×8 m sample pot which includes 14 sub-plots was set up along the slope in Hongshi Forestry Farm of Baihe Forestry Bureau (127°55′E, 42°30′ N), Jilin Province in August 2002. Community structure, soil moisture contents at 0–10 cm and 10–20 cm in depth, water content of litter as well as the contents of C, N and P of litter, living leaves and branches in the broad-leaved/Korean pine (Pinus korraiensis) forest were measured in each sub-plot on different slope positions. The analytical results showed that there existed an obvious soil moisture gradient along the slope: upper slope <middle slope< lower slope. The difference in soil moisture contents on different positions of slope led to a change of the stand structure of the braod-leaved/Korean pine forest. The proportion ofQuercus mongolica gradually increased with the decrease of soil moisture content and that of other major tree species in the broad-leaved/Korean pine forest gradually decreased or disappeared. The dynamic of soil moisture contents in the litter layer was as same as that in mineral soils. The decomposition rates of the litter on different slope positions were different and the dry weights of existent litter varied significantly. The soil nutrients in the litter on the lower slope was richer than that on the upper slope due to the different stand structure on the different slope positions. The moisture content and nutrient contents of soil had effects on the composition, decomposition, and the nutrient release of litter, thus affecting stands growth and stand structure and finally leading to the change of ecosystem. Key words Soil moisture gradient - nutrient - Stand structure - Broad-leaved/Korean pine forest CLC number S718.5 Document code A Foundation item: This study was supported by the NKBRSF (G1999043407-1), Tackle Key Problem of Science and technology of China (2001BA510B-07), Knowledge Innovation Program of the Chinese Academy of Sciences (KZCX2-406, SCXZD0101), NKTRDP (2001BA510B-07. 2002BA516A20).Biography: WANG Yan (1970-), female, Ph. D, associate professorResponsible editor: Song Funan 展开更多
关键词 Soil moisture gradient NUTRIENT Stand structure Broad-leaved/korean pine forest
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Method and standard for selecting elite nut trees of Korean pine 被引量:8
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作者 杨凯 谷会岩 +2 位作者 扬凯 李春英 杨逢建 《Journal of Forestry Research》 SCIE CAS CSCD 2001年第2期84-88,146,共5页
The fruit-bearing quantities of nut Korean pines (Pinus Koraiensis) of natural stands in Changbai Mountain, Xiaoxing'an Mountain, and Wanda Mountain and of artificial forest in Hegang area of Heilongjiang Province... The fruit-bearing quantities of nut Korean pines (Pinus Koraiensis) of natural stands in Changbai Mountain, Xiaoxing'an Mountain, and Wanda Mountain and of artificial forest in Hegang area of Heilongjiang Province were investigated and measured by seed collection of singletree during 1988–1998. In order to evaluate the elite nut tree of fructification, the characteristics of fructification of Korena pine, including, the fruit-bearing quantity, output of seed, quantity of cone, cone size, seed size, the ratio of null seed by solid seed, seed percentage of cone, rate of the cones infested with pest, and fruit-bearing index, etc., were analyzed with the variance analysis, multiple comparison and stepwise regression to obtain the contribution ratio of each fruit-bearing factor to fruit-bearing quantity. The multiple correlation factors and the partial correlation factors for fruit-bearing quantities of Korean pine were determined for different geographical areas, and the cone length, thousand-grain-weight, and the seed percentage of cone were considered as important indices for selection of elite trees. The method of modified weighted coefficients was adopted to select the elite nut trees of Korean pine. Standards for selecting elite nut trees from the natural stands and artificial forest of Korean pine were established. This study could provde selection method and standard of elite nut trees for setting up seed orchard of Korean Pine. 展开更多
关键词 korean pine Elite nut tree Selection method
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