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Quantifying the Accuracy of Digital Hemispherical Photography for Leaf Area Index Estimates on Broad-Leaved Tree Species

Carlo Gilardelli, Francesca Orlando, Ermes Movedi, Roberto Confalonieri
2018 Sensors  
Digital hemispherical photography (DHP) has been widely used to estimate leaf area index (LAI) in forestry.  ...  The purpose of this study was to quantify the impact of user's subjectivity on DHP LAI estimates for broad-leaved woody canopies using the software Can-Eye.  ...  Precision (repeatability and reproducibility) of digital hemispherical photography (Can-Eye software) in estimating leaf area index (LAI) in tree species. r: repeatability limit; RSDr: relative standard  ... 
doi:10.3390/s18041028 pmid:29596376 pmcid:PMC5948923 fatcat:tajypniwzvcero7ih56yquouyy

Estimate of Leaf Area Index in an Old-Growth Mixed Broadleaved-Korean Pine Forest in Northeastern China

Zhili Liu, Guangze Jin, Yujiao Qi, Ben Bond-Lamberty
2012 PLoS ONE  
Second, by periodically combining true LAI (May 1 st ) with the seasonality of LAI for deciduous and coniferous species throughout the leaf-expansion season (from May to August), we estimated LAI of each  ...  Leaf area index (LAI) is an important variable in the study of forest ecosystem processes, but very few studies are designed to monitor LAI and the seasonal variability in a mixed forest using non-destructive  ...  Chen for providing us with the technology to collect and analyze the data. We greatly appreciate input of editor and two anonymous reviewers for improving this manuscript.  ... 
doi:10.1371/journal.pone.0032155 pmid:22427822 pmcid:PMC3302887 fatcat:4xtruu7cuvcuxaqwb42vwhfafm

Review of methods for in situ leaf area index determination

Inge Jonckheere, Stefan Fleck, Kris Nackaerts, Bart Muys, Pol Coppin, Marie Weiss, Frédéric Baret
2004 Agricultural and Forest Meteorology  
Rapid, reliable and objective estimations of leaf area index (LAI) are essential for numerous studies of atmosphere-vegetation interaction, as LAI is very often a critical parameter in process-based models  ...  Further testing and defining of a standardised field protocol for digital hemispherical photography is however needed to improve this technique to achieve the standards of an ideal device.  ...  For broad-leaved trees with flat leaves, this definition is applicable because both sides of a leaf have the same surface area.  ... 
doi:10.1016/j.agrformet.2003.08.027 fatcat:2lgm4ygoazetzgjllqe7p2ryni

Applicability of the Hemispherical Photography to Leaf Area Index Estimation in a Stand of Bamboo, Phyllostachys pubescens

Akio Inoue, Kazukiyo Yamamoto, Nobuya Mizoue, Kotaro Sakuta, Kyoichi Otsuki
2014 Journal of Forest Planning  
We evaluate an applicability of the hemispherical photography for estimating leaf area index (LAI) in a stand of bamboo, Phyllostachys pubescens Mazel ex Houz.  ...  In conclusion, the hemispherical photography should be accepted as an effective alternative for estimating LAI in a stand of P. pubescens.  ...  We also thank anonymous reviewers for their constructive comments on an earlier version of this paper. LITERATURE CITED  ... 
doi:10.20659/jfp.19.2_53 fatcat:c2dwkkygozasrn7te5otxt2qtq

Ground-based measurements of leaf area index: a review of methods, instruments and current controversies

N. J. J. Breda
2003 Journal of Experimental Botany  
Leaf area index (LAI) is the total one-sided area of leaf tissue per unit ground surface area.  ...  It is also one of the most dif®cult to quantify properly, owing to large spatial and temporal variability.  ...  Acknowledgements I gratefully acknowledge the help provided by the staff of all the companies dealing with the area of leaf area index measurements.  ... 
doi:10.1093/jxb/erg263 pmid:14565947 fatcat:rm5ds4jm35ay3lr2fys7pcgbt4

How to quantify tree leaf area index in an open savanna ecosystem: A multi-instrument and multi-model approach

Youngryel Ryu, Oliver Sonnentag, Tiit Nilson, Rodrigo Vargas, Hideki Kobayashi, Rebecca Wenk, Dennis D. Baldocchi
2010 Agricultural and Forest Meteorology  
John Norman for constructive comments on leaf inclination angle and clumping index, Dr.  ...  Craig Macfarlane for helpful comments on digital cover photography, Dr. Qi Chen for providing LiDAR data, Dr.  ...  Usually, g E is assumed to be 1 for deciduous broad-leaved trees (Chen, 1996) .  ... 
doi:10.1016/j.agrformet.2009.08.007 fatcat:auquxkree5hgxecb5ukrgyc4uu

The estimation of canopy attributes from digital cover photography by two different image analysis methods

F Chianucci, U Chiavetta, A Cutini
2014 iForest : Biogeosciences and Forestry  
Leaf area index (LAI) estimates from the two image analysis methods were compared with reference LAI measurements obtained through the use of litter traps to measure leaf fall.  ...  Digital hemispherical photography (DHP) is the most widely used photographic technique for canopy description.  ...  We thank an anonymous reviewer for the helpful and insightful comments, which help us to greatly improve the manuscript.  ... 
doi:10.3832/ifor0939-007 fatcat:hef7vrtl65bmhohfc5zwdkkij4

Leaf area index of boreal forests: Theory, techniques, and measurements

Jing M. Chen, Paul M. Rich, Stith T. Gower, John M. Norman, Steven Plummer
1997 Journal of Geophysical Research  
Leaf area index (LAI) is a key structural characteristic of forest ecosystems because of the role of green leaves in controlling many biological and physical processes in plant canopies.  ...  to obtain quick and accurate LA1 measurements. 29,429 29,430 CHEN ET AL.: LEAF AREA INDEX OF BOREAL FORESTS  ...  Allometric equations can be used to scale tree-level estimates of leaf area to the stand-level by measuring the diameter and species of all trees in a plot of known area and applying the appropriate allometric  ... 
doi:10.1029/97jd01107 fatcat:gkntvfa2krdqlmjzdktruadqiu

Spatial Variability of Leaf Area Index in Homogeneous Forests Relates to Local Variation in Tree Characteristics

Raphael Bequet, Matteo Campioli, Vincent Kint, Bart Muys, Jan Bogaert, Reinhart Ceulemans
2012 Forest Science  
The accuracy of indirect 9 methods to quantify stand leaf area index (LAI) is often unknown, and intensive sampling strategies are 10 required.  ...  Defining leaf-area index for non-flat leaves. Plant Cell 347 Environ. 15:421-429. 348 349 Chen, J.M., and J. Cihlar. 1995.  ...  deviation of leaf area index (LAI) estimates from plot (see Fig . 1B).  ... 
doi:10.5849/forsci.10-123 fatcat:f6qefwu55zhrjl4o3bimynj5im

Retrieving Leaf Area Index (LAI) Using Remote Sensing: Theories, Methods and Sensors

Guang Zheng, L. Monika Moskal
2009 Sensors  
The ability to accurately and rapidly acquire leaf area index (LAI) is an indispensable component of process-based ecological research facilitating the understanding of gas-vegetation exchange phenomenon  ...  at an array of spatial scales from the leaf to the landscape.  ...  Acknowledgements Funding has been provided by the Precision Forestry Cooperative (PFC), University of Washington (UW).  ... 
doi:10.3390/s90402719 pmid:22574042 pmcid:PMC3348792 fatcat:dvnggvw55vdvpi4h7a4woyjh6q

Quantitative phenological observations of a mixed beech forest in northern Switzerland with digital photography

Hella Ellen Ahrends, Robert Brügger, Reto Stöckli, Jürg Schenk, Pavel Michna, Francois Jeanneret, Heinz Wanner, Werner Eugster
2008 Journal of Geophysical Research  
We estimated the date of leaf emergence based on the levels of the extracted red, green and blue colors. Comparisons with validation data were in accordance with the phenology of the observed trees.  ...  Image analysis was conducted separately on a set of regions of interest representing two different tree species during spring in 2005 and 2006.  ...  We are grateful to the National Center of Competence in Research on Climate (NCCR Climate) for supporting this project.  ... 
doi:10.1029/2007jg000650 fatcat:f7xp7t4mfjhbpcd5cwnzrvk5pq

A dataset of leaf inclination angles for temperate and boreal broadleaf woody species

Francesco Chianucci, Jan Pisek, Kairi Raabe, Luca Marchino, Carlotta Ferrara, Piermaria Corona
2018 Annals of Forest Science  
A dataset of leaf inclination angles for temperate and boreal broadleaf woody species.  ...  Acknowledgments We thank the anonymous reviewer and the handling editor Marianne Peiffer for the constructive comments, which improved the original version of the manuscript.  ...  indirect estimation of leaf area index (Campbell and Norman 1989; Myneni et al. 1989; Ross 1981) .  ... 
doi:10.1007/s13595-018-0730-x fatcat:rcu6rp7p2vdova7qrwiesdbn7a

An overview of in situ digital photographic approaches to estimate forest canopy attributes

Francesco Chianucci
2019 Canadian Journal of Forest Research  
The mean element width is defined as the square root of half the largest projected leaf area for broad leaves.  ...  Here we describe the work related to the estimation of leaf area index (LAI) and specific leaf area (SLA), or its inverse, the leaf mass per area (LMA).  ...  Species Annex III -Measured Leaf Angle Distributions Direct measurements of leaf angle distributions are available from the main forest tree species (exemplary data compiled with support by Jan Pisek  ... 
doi:10.1139/cjfr-2019-0055 fatcat:2qnw5hj2rzah3adxjb6rpxg4xe

Evaluation and correction of optically derived leaf area index in different temperate forests

Z Liu, G Jin, M Zhou
2016 iForest : Biogeosciences and Forestry  
In this paper, we assessed the accuracy of digital hemispherical photography (DHP) and the LAI-2000 for the estimation of effective LAI (Le) by comparison with litter collection LAI (LAIlit) in four mixed  ...  Our results demonstrate that the above factors affect the estimation of LAI by optical methods, thus the species composition of a forest stand should be seriously considered in order to improve the accuracy  ...  Chen for the comments of the revised manuscript. We also would like to express our gratitude to the anonymous reviewers for their constructive and valuable comments on the manuscript.  ... 
doi:10.3832/ifor1350-008 fatcat:kia4i4hqcvaoroy7a3bxgsv26u

Continuous observation of tree leaf area index at ecosystem scale using upward-pointing digital cameras

Youngryel Ryu, Joseph Verfaillie, Craig Macfarlane, Hideki Kobayashi, Oliver Sonnentag, Rodrigo Vargas, Siyan Ma, Dennis D. Baldocchi
2012 Remote Sensing of Environment  
Understanding the dynamics of leaf area index (LAI) at ecosystem scale is critical for evaluating and modeling the response of vegetation to environmental variability and change.  ...  The digital camera-derived LAI, corrected for clumping effects, agreed well (r 2 = 0.94, root mean square error = 0.05) with independent estimates of LAI from litterfall traps and the LAI-2000 Plant Canopy  ...  Thus, the incorporation of the gap fraction estimates into Beer's Law quantifies plant area index (PAI) instead of LAI.  ... 
doi:10.1016/j.rse.2012.08.027 fatcat:stuv7ux3ofcmfgrgwl5evdcqd4
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