• 한국제4기학회지
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• 제18권2호통권23호
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• pp.107-107
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• 2004

In this paper we have introduced some results of study on stand growth pattern and stand structure of larch forest which are located in selected forest sites of Khangai and Gobi-Altai mountain ranges of Mongolia. Our investigations showed that growth intensity and stand structure in western Mongolia are very specific from the other forest vegetation zones of Mongolia. Studies on the stand structure and growth trend indicate that tree types of stand structure and different types of growth of Larix sibrica are very common in Western Mongolia. These peculiarities of stand structure and growth of larch stands in Western Monolia could be used for inventory work and an improvement of the forest management in Western Mongolian region. The larch tree is the dominant tree species in Western Mogolia. Forest cover of the region is about 15%, which is two times higher than the country's average. In this region forest area is divided into 4 forest sub-regions: the Central Khangai, Western Khangai, North Eastern Khangai and South Easterun Khangai sub-regions including taiga, pseudo taiga, sub taiga, sub-alpine and forest steppe belts. Silviculture practices and forest research management request to study forest growth trends in local and general conditions, which means to indicate a change of taxonomic characteristics of stand from time to time including diameter, height, basal area, growth stock etc. The forest management practice mostly uses tables of forest growth and yield based on the results of long term research on forest growth. Forest yield tables and other relevant forest standards of Russia are used for the forest inventory and forest management. They are not able to determine forest structure and growth peculiatities of Mongolian forests. Studies on forest resource assessment in Mongolia indicate that after logging operations and forest fires the natural regeneration of desired species such as pine and larch often does not succeed. This situation forces to take a different approach of forest management and silviculture practice depending on the stand structure and growth rate of the forest stands. According to our investigation in last years, forest growth pattern of larch forest depends mostly on stand structure, stand age and growth condition including forest soil, climate and location in different slopes. Due to improve environmental function of forest ecosystem in the region, it is needed to conduct very comprehensive study of high mountain forest ecosystem in selected sub-regions.

• 대한원격탐사학회지
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• 제40권2호
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• pp.123-139
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• 2024

Forest vertical structure is vital for comprehending ecosystems and biodiversity, in addition to fundamental forest information. Currently, the forest vertical structure is predominantly assessed via an in-situ method, which is not only difficult to apply to inaccessible locations or large areas but also costly and requires substantial human resources. Therefore, mapping systems based on remote sensing data have been actively explored. Recently, research on analyzing and classifying images using machine learning techniques has been actively conducted and applied to map the vertical structure of forests accurately. In this study, Sentinel-2 and digital surface model images were obtained on two different dates separated by approximately one month, and the spectral index and tree height maps were generated separately. Furthermore, according to the acquisition time, the input data were separated into cases 1 and 2, which were then combined to generate case 3. Using these data, forest vetical structure mapping models based on random forest, support vector machine, and extreme gradient boost(XGBoost)were generated. Consequently, nine models were generated, with the XGBoost model in Case 3 performing the best, with an average precision of 0.99 and an F1 score of 0.91. We confirmed that generating a forest vertical structure mapping model utilizing bi-seasonal data and an appropriate model can result in an accuracy of 90% or higher.

• 한국산림과학회지
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• 제97권2호
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• pp.144-151
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• 2008

Using 8 isozyme polymorphic loci as gene markers, we studied the spatial distribution of genotypes in a naturally regenerated uneven-aged Eastern Siberian Fir (Abies nephrolepis Max.) stand (1ha, $100{\times}100m$) on Mt. Ohdae in northeastern South Korea. Gregorius' distograms and Moran's I correlograms revealed no evidence of significant genetic structure at three spatial classes of 5 m, 10 m, and 20 m. Extensive gene flow, due to the long distance dispersal of pollen and seeds in A. nephrolepis, may account for the lack of fine-scale spatial structure. Alternatives would be overlapping seed shadows caused by high densities of A. nephrolepis adult trees (160 trees/ha) and/or intraspecific competition resulting in extensive thinning within maternal half-sib groups.

• 환경영향평가
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• 제17권5호
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• pp.279-288
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• 2008

Vertical forest distribution is one of the important factors to understand various ecological mechanism such as succession, disturbance and environmental effects. LiDAR data provide information, both the horizontal and vertical distribution of forest structure. The laser scanner survey provided a point cloud, in which the x, y, and z coordinates of the points are known. The objectives of this study were 1) to analyze factors of forest structure such as individual tree isolation, tree height, canopy closure and tree density using LiDAR data and 2) to compare the forest structure between outer and interior forest. The paper conducted to extract the individual tree using watershed algorithm and to interpolate using the first return of LiDAR data for yielding digital surface model (DSM). The results of the study show characters of edge such as more isolated individual trees, higher density, lower canopy closure, and lower tree height than those of interior forest. LiDAR data is to be useful for analyzing of forest structure. Further study should be undertaken with species for more accurate results.

• 환경생물
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• 제23권2호
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• pp.141-145
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• 2005

본 연구는 전나무림 생태계 이해를 위하여 전나무 임분구조에 관한 기초자료를 수집하는 조사의 일부이다. Leibundgut(1981)의 임분구조 분류에 따르면 A,B임분은 쇠퇴기로 추정되며 C는 갱신기, D는 안정기와 쇠퇴기 복합형, E는 불안정한 시기인 택벌상으로 추정된다.

• 한국환경과학회지
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• 제21권2호
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• pp.135-144
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• 2012

This study aims at classifying and analyzing the vegetation structure of Castanopsis sieboldii forest, one of the evergreen broad-leaved forests found under the warm-temperate climate of Korea. It is also compared with the ones of the Castanopsis sieboldii forest in Japan where most similar such forest of Korea, to find unique vegetation structures of the only Korean forest. Vegetation structure of Korean Castanopsis sieboldii forest was divided into two units at the level of community units both of Ardisia japonica-Castanopsis sieboldii community and Ardisio-Castanopsietum sieboldii association. The association carries similar type with the vegetation system of Japan, but any subunits differentiated with the Japan were found vary much. Hierarchical cluster analysis brings in similar result with the analysis on the vegetation structure as well.

• 한국산림과학회지
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• 제96권5호
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• pp.572-579
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• 2007

Tree species diversity is an important aspect of forest ecosystem stability. Tree species inventories at defined sites and in minimum diameter classes give a reliable indicator of the diversity level as well as the structural stability level of a study site. This study was conducted to investigate the species composition and the stand structure of the natural forest, timber-harvested forest (logged-over forest) and degraded forest of the Oak-twin Township in the Bago Yoma Region of Myanmar. Natural forest showed the highest family and species richness in all the investigated forests. At the family level, Verbenaceae occupied the highest importance value index (IVI) in all the forest stands while teak (Tectona grandis Linn. f.) occupied the highest IVI at the species level. However, the small diameter classes of T. grandis and other commercial species were less than those of big diameter classes in all the investigated forests. This abnormal pattern of diameter distribution could be a problem for the sustainable production of commercial timber species in the near future.

• Journal of Forest and Environmental Science
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• 제22권1호
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• pp.50-57
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• 2006

일본에서 2004년도에 발행된 산림토목 목제구조물 시공 매뉴얼에 실려 있는 산림토목 목제구조물 설계지침은 총설, 목재의 이용과 특성, 조사, 계획 및 설계 등으로 구성되어 있으며, 이 논문에서는 설계 및 시공에 대하여 분석하였다. 분석 결과, 설계편에는 목재의 사용 환경과 열화, 구조, 수종의 선정, 치수 표시 등의 통일, 안정성과 강도의 검토, 목재의 강도, 목재의 치수의 허용 폭 등에 대하여 제시되어 있다. 또한 시공편에는 목재의 품질 확보, 방부처리 등의 품질 확인, 목제구조물의 기능 확보 방법, 목재열화의 정기적인 조사방법과 정성적인 판정기준 및 정량적인 조사방법 등에 대하여 설명되어 있다.

• 한국조경학회지
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• 제28권3호
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• pp.13-24
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• 2000

In urban area, urban forests work as an ecological center that mitigates the environmental pollution of the area. In order to maintain the ecological function of a forest, the management method should be established based on ht through investigation of the vegetation structure of the forest. In this study, the vegetation structure of Namsan in Kyungju area was investigated in order to study the ecological value of Namsan and to suggest a desirable management alternative. 21 plots were selected as survey areas. Using the TWINSPAN technique, the forest of Namsan was classified into four communities: Quercus serrata community(I), Castanea crenata-Q. serrata-Q. mongolica community(II), Pinus densiflora community(III) and P. densiflora-P. rigida-Robinia pseudoacacia community(IV). The survey results were summarized by five: 1) the distribution of vegetation showed 2) P. densiflora was the absolutely dominant species in Namsan, 3) number of the average species was 12.6$^{\circ}$$\pm$3.1, 4) number of individual was 131.1$^{\circ}$$\pm$47.8 per a plot(100$m^2$), 5) the results of annual ring analysis revealed that the age of P. densiflora in Namsan was about 3 0$^{\circ}$~60$^{\circ}$years old. From the above results, it was found out that the forest has two problems. One thing is maintenance of P.densiflora against succession, another is artificial forest dispersion. The problems of Namsan forest management will be solved with further studies related.

• 환경생물
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• 제29권4호
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• pp.345-352
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• 2011

내설악 전나무 자연림 임분구조를 좀 더 체계적으로 이해하기 위하여 종다양성 추정에 사용되는 Shannon-Weaver-Index를 응용한 Herles의 구조표현인자 다양성 계산 방법을 도입하여 12개의 임분을 조사하였다. 임분 구조 변화는 당연히 phase의 변화에 종속되지만 개개인자들 간의 연관에서 자연림의 특성이 재확인되었다. 우선 내설악 전나무 자연림의 구조는 표현인자 다양성의 결과에서 보이는 것처럼 다양성이 상대적으로 낮은 것으로 나타났다. 인자 간의 상관에서 종다양성은 구조 변화 관련 전체 인자 (다양성)와 미약한 관계만 보이며, 어느 정도 설명이 가능한 연관을 보이는 것으로는 개체수였으며, 개체수가 증가할수록 임분구조 전체의 다양성은 떨어지는 결과를 보인다. 입목축적이나 고사목 축적은 대부분 조사구에서 천연갱신고도와 연관을 보이며 다른 인자와는 별다른 관계를 보이지 않는 것으로 나타났다. 타 구조표현인자 서로서로의 연관은 천연갱신고도와 관련하여 울폐도나 수관면적, 형태 등과 연관을 보였으며 수고나 흉고직경은 타 인자들과 별다른 연관을 보이지 않았다. 전체적으로 내설악 전나무림 구조변화 이해에 도움을 주는 결과를 가져왔지만 좀 더 많은 조사구에 대한 조사가 필요하리라 본다.