• 제목/요약/키워드: TREE HEIGHT

검색결과 830건 처리시간 0.038초

Current Status of Tree Height Estimation from Airborne LiDAR Data

  • Hwang, Se-Ran;Lee, Im-Pyeong
    • 대한원격탐사학회지
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    • 제27권3호
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    • pp.389-401
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    • 2011
  • Most nations around the world have expressed significant concern in the climate change due to a rapid increase in green-house gases and thus reach an international agreement to control total amount of these gases for the mitigation of global warming. As the most important absorber of carbon dioxide, one of major green-house gases, forest resources should be more tightly managed with a means to measure their total amount, forest biomass, efficiently and accurately. Forest biomass has close relations with forest areas and tree height. Airborne LiDAR data helps extract biophysical properties on forest resources such as tree height more efficiently by providing detailed spatial information about the wide-range ground surface. Many researchers have thus developed various methods to estimate tree height using LiDAR data, which retain different performance and characteristics depending on forest environment and data characteristics. In this study, we attempted to investigate such various techniques to estimate tree height, elaborate their advantages and limitations, and suggest future research directions. We first examined the characteristics of LiDAR data applied to forest studies and then analyzed methods on filtering, a precedent procedure for tree height estimation. Regarding the methods for tree height estimation, we classified them into two categories: individual tree-based and regression-based method and described the representative methods under each category with a summary of their analysis results. Finally, we reviewed techniques regarding data fusion between LiDAR and other remote sensing data for future work.

Design and Implementation of System for Estimating Diameter at Breast Height and Tree Height using LiDAR point cloud data

  • Jong-Su, Yim;Dong-Hyeon, Kim;Chi-Ung, Ko;Dong-Geun, Kim;Hyung-Ju, Cho
    • 한국컴퓨터정보학회논문지
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    • 제28권2호
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    • pp.99-110
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    • 2023
  • 논문은 LiDAR 점군 데이터를 사용하여 흉고 직경과 수고를 예측하는 ForestLi 시스템을 제안한다. ForestLi 시스템이 LiDAR 점군 데이터를 처리하는 과정은 다음과 같이 여러 단계로 진행된다. 다운샘플링, 이상점 제거, 지표면 분할, 지표면 정규화, 수간 추출, 개체목 분할, 흉고 직경 측정, 수고 측정. LiDAR 점군 데이터를 처리하는 상용 시스템 LiDAR360은 하측 식생과 개체목 분할 오류를 사용자가 직접 수정해야 한다. ForestLi 시스템은 하측 식생에 해당하는 LiDAR 점군 데이터를 자동으로 제거한다. 결과적으로 ForestLi 시스템이 LiDAR360보다 전체 수행시간을 줄이고, 흉고 직경과 수고 예측의 정확성을 높였다. 실험을 통해서 제안된 ForestLi가 LiDAR360 시스템보다 흉고 직경과 수고 측정의 정확성과 전체 실행시간 측면에서 우수하다는 것을 보여주었다.

'Fuji'/M.9 사과나무에 있어 세장방추형의 수고가 영양생장, 생산성 및 노동력에 미치는 영향 (Influence of Tree Height on Vegetative Growth, Productivity, and Labour in Slender Spindle of 'Fuji'/M.9 Apple Trees)

  • 양상진;박무용;송양익;사공동훈;윤태명
    • 생물환경조절학회지
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    • 제18권4호
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    • pp.492-501
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    • 2009
  • 재식거리 $3.2{\times}1.2m$로 심어 수고 2.5m의 세장방추형으로 관리해 오던 '후지'/M.9 사과나무를 재식 6년차부터 2년 동안 수고 4.0m로 관리하였다. 이후 재식 8년차에 수고를 2.5m(대조구), 3.0m, 3.5m, 4.0m로 조절하고 수고에 따른 2년간의 생산성 및 노동력을 비교하였다. 대조구인 수고 2.5m를 기준으로 하여 처리에 따른 10a당 생산량을 비교해 보면 첫해에는 수고 4.0m, 3.5m, 3.0m에서 각각 46%, 25%, 4%, 2년차에는 17%, 12%, 10% 증가하였다. 수고에 따른 과실 품질에 있어서는 가용성 고형물 함량은 2개년 모두 수고 2.5m가 가장 높았으나, 착색정도는 수고에 따른 뚜렷한 차이가 없었다. 노동력은 수고가 높아질수록 증가하였으나, 노동력에 따른 과실생산량은 수고가 낮을수록 증가하였다. 조수입과 순수입은 2005년의 경우 수고가 높아질수록 증가하였으나, 2006년은 수고 2.5m가 가장 높았지만 통계적 유의차는 없었다. 따라서 수고에 따른 생산성, 노동력, 경제성을 고려해 볼때 적정수고는 3.0~3.5m인 것으로 판단되었다.

계절별 항공라이다 자료에 의한 수고 추정 (Estimation of Tree Heights from Seasonal Airborne LiDAR Data)

  • 전민철;정태웅;어양담;김진광
    • 한국측량학회지
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    • 제28권4호
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    • pp.441-448
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    • 2010
  • 본 논문은 계절별로 획득된 항공라이다 자료로부터 수고를 추정하여 수관울폐도와 자료융합에 따른 영향을 분석하였다. 수고추정은 수목에서 반사되는 신호(First Return : FR)와 지표에서 반사되는 신호(Last Return : LR)를 추출하고, 영상분할을 통해 수목개체를 가정하여 개체목별 수고를 획득하는 방법을 적용하였다. 계절별 자료를 통해 획득한 각 수고 자료와 융합자료로부터 획득한 수고의 결과를 비교하였으며, 수고측정기를 사용하여 현지 측정을 하여 정확성을 비교하고, 항공라이다를 통해 획득한 자료들을 융합한 결과에 대한 그 활용성을 검토하였다. 실험 결과, 수목개체를 위한 영상분할 결과는 0.5미터 점군간격보다 1미터 간격이 현지조사 결과와 가까웠으며, 수목고의 경우 각 계절별 자료보다 융합자료를 활용한 결과가 현지 측정 결과에 접근하고 있음을 알 수 있었다.

Vertical Distribution of Foraging Tits in Mixed Species Flocks in Urban Forests

  • Lee, Sang-Don
    • The Korean Journal of Ecology
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    • 제22권2호
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    • pp.65-68
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    • 1999
  • In December-January of 1996-1997 and 1997-1998, information was gathered about vertical distribution of foraging sites of tits in 34 flocks in coniferous and deciduous forests. There was a significant effect of forest type on the distribution of foraging sites of each species. Habitat was classified into 5 height layers vertically: ground, bushes (usually<1.5 m, up to 3 m), tree layer 1 (up to 1/3 of tree height), tree layer 2 (1/3-2/3 tree height). and tree layer 3 (>2/3 tree height). There were differences among species: great tit (Parus major) foraged mostly on the ground, coal tit (P. ater) and long-tailed tit (Acrocephalus caudatus) - on the highest tree layer, marsh tit (P. palustris) was often seen on bushes, and varied tit (P. varius) - in tree layer 2. Smaller species used upper and outer parts of trees. suggesting that, like in most other similar studies. larger dominant species prevented smaller species from using inner parts of trees.

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Allometry, Basal Area Growth, and Volume Equations for Quercus mongolica and Quercus variabilis in Gangwon Province of Korea

  • Choi, Jung-Kee;You, Byung-Oh;Burkhart, Harold E.
    • 한국산림과학회지
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    • 제96권2호
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    • pp.189-196
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    • 2007
  • Allometry, basal area equations, and volume equations were developed with various tree measurement variables for the major species, Quercus mongolica and Quercus variabilis, in Korean natural hardwood forests. For allometry models, the relationships between total height-DBH, crown width-DBH, height to the widest portion of the crown-total height, and height to base of crown-total height were investigated. Multiple regression methods were used to relate annual basal area growth to tree variables of initial size (DBH, total height, crown width) and relative size (relative diameter, relative height) as well as competition measures (competition index, crown class, exposed crown area, percent exposed crown area, live crown ratio). For tree volume equations, the combined-variable and Schumacher models were fitted with DBH, total height and crown width for both species.

CONIFER FOREST BIOMASS ESTIMATION USING MULTI ANGLE SPECTRUM OBSERVATION

  • Kajiwara, Koji;Ono, Yuhsaku;Honda, Yoshiaki
    • 대한원격탐사학회:학술대회논문집
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    • 대한원격탐사학회 2008년도 International Symposium on Remote Sensing
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    • pp.394-397
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    • 2008
  • This research aimed at developing a technique for estimating the tree height using BRF (Bi-directional Reflectance Factor) through the clarification of the relation between shape of the tree crown and the tree height and the relations between the shape of the tree crown and BRF. This paper, reports the results of analyses of data acquired by field measurements done to clarify relation between crown shape and tree height.

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A STUDY ON 3D STRUCTURE DETECTION FOR FOREST TREES USING REFLECTED SPECTRUM INFORMATION

  • Ono, Yuhsaku;Kajiwara, Koji;Honda, Yoshiaki
    • 대한원격탐사학회:학술대회논문집
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    • 대한원격탐사학회 2007년도 Proceedings of ISRS 2007
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    • pp.345-348
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    • 2007
  • This research aimed at developing a technique for estimating the tree height using BRF (Bi-directional Reflectance Factor) through the clarification of the relation between shape of the tree crown and the tree height and the relations between the shape of the tree crown and BRF. This paper, reports the results of analyses of data acquired by field measurements done to clarify relation between crown shape and tree height.

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Calculation of Tree Height and Canopy Crown from Drone Images Using Segmentation

  • Lim, Ye Seul;La, Phu Hien;Park, Jong Soo;Lee, Mi Hee;Pyeon, Mu Wook;Kim, Jee-In
    • 한국측량학회지
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    • 제33권6호
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    • pp.605-614
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    • 2015
  • Drone imaging, which is more cost-effective and controllable compared to airborne LiDAR, requires a low-cost camera and is used for capturing color images. From the overlapped color images, we produced two high-resolution digital surface models over different test areas. After segmentation, we performed tree identification according to the method proposed by , and computed the tree height and the canopy crown size. Compared with the field measurements, the computed results for the tree height in test area 1 (coniferous trees) were found to be accurate, while the results in test area 2 (deciduous coniferous trees) were found to be underestimated. The RMSE of the tree height was 0.84 m, and the width of the canopy crown was 1.51 m in test area 1. Further, the RMSE of the tree height was 2.45 m, and the width of the canopy crown was 1.53 m in test area 2. The experiment results validated the use of drone images for the extraction of a tree structure.

수목차폐율을 고려한 자동상관매칭 수치고도 결과 분석 (Analysis of Ground Height from Automatic Correlation Matching Result Considering Density Measure of Tree)

  • 어양담
    • Spatial Information Research
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    • 제15권2호
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    • pp.181-187
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    • 2007
  • 수치고도자료를 생성하기 위해서, 항공기 혹은 위성에 탑재된 센서로부터 획득한 입체영상으로부터 자동상관매칭기법에 의해 고도값을 획득하는 연구가 수행되어 왔다. 자동상관매칭에 의한 결과값은 센서의 각도 및 수목 등에 의해 지표고도를 직접 추출하는데는 한계가 있고 영상내 지형지물 분포에 의해 고도값의 수정, 편집량이 결정된다. 본 연구는 수목차폐율과 수목고 자료가 자동상관매칭 고도 결과값에 미치는 영향을 분석하였다.

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