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Extracting Leaf Area Index by Sunlit Foliage Component from Downward-Looking Digital Photography under Clear-Sky Conditions

Yelu Zeng, Jing Li, Qinhuo Liu, Ronghai Hu, Xihan Mu, Weiliang Fan, Baodong Xu, Gaofei Yin, Shengbiao Wu
2015 Remote Sensing  
In this study, a new LAI extraction method by the sunlit foliage component from downward-looking digital photography under clear-sky conditions is proposed.  ...  The development of near-surface remote sensing requires the accurate extraction of leaf area index (LAI) from networked digital cameras under all illumination conditions.  ...  LAI from downward-looking digital photography under clear-sky conditions.  ... 
doi:10.3390/rs71013410 fatcat:bnoxdiylmnaoblnaq42vbt742m

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  ...  The value of optical LAI measurements by means of hemispherical photography has already been demonstrated in previous studies.  ...  the canopy looking downward.  ... 
doi:10.1016/j.agrformet.2003.08.027 fatcat:2lgm4ygoazetzgjllqe7p2ryni

Assessment of a photon recollision probability based forest reflectance model in European boreal and temperate forests

Aarne Hovi, Daniel Schraik, Jan Hanuš, Lucie Homolová, Jussi Juola, Mait Lang, Petr Lukeš, Jan Pisek, Miina Rautiainen
2021 Remote Sensing of Environment  
For the first time, a p-based approach to modeling forest reflectance was tested in a wide range of differently structured forests from different biomes.  ...  The model requires only few structural parameters and the spectra of foliage, woody elements, and forest floor as input.  ...  This study has received funding from the European Research Council (ERC) under the European Union's Horizon 2020 research and innovation programme (grant agreement No 771049).  ... 
doi:10.1016/j.rse.2021.112804 fatcat:yaqdnjhjozeuhccs7sien4pt2i

Monitoring vegetation phenology using an infrared-enabled security camera

Anika R. Petach, Michael Toomey, Donald M. Aubrecht, Andrew D. Richardson
2014 Agricultural and Forest Meteorology  
Digital repeat photography, in 3 particular, can characterize the seasonality of canopy greenness.  ...  camera NDVI is almost identical to that of NDVI 11 measured using narrow-band radiometric instruments, or as observed from space by the MODIS 12 platform.  ...  constant (k i ) determined under natural (sunlit) 20 conditions using a Spectralon panel. 21 !  ... 
doi:10.1016/j.agrformet.2014.05.008 fatcat:raieguplnfb4ppsull4v4vkuu4

Crown Structure Explains the Discrepancy in Leaf Phenology Metrics Derived from Ground- and UAV-Based Observations in a Japanese Cool Temperate Deciduous Forest

Noviana Budianti, Hiromi Mizunaga, Atsuhiro Iio
2021 Forests  
in total) characterized by different crown structures.  ...  Unmanned aerial vehicles (UAV) provide a new platform for monitoring crown-level leaf phenology due to the ability to cover a vast area while offering branch-level image resolution.  ...  checked using foliage photographs that had been taken from the ground by a digital camera (Figure S3 inset photographs).  ... 
doi:10.3390/f12040425 fatcat:tx3kkjjaerbgfb5nknudaoh3au

Radiative Transfer Modelling for the characterisation of natural burnt surfaces

Philip Lewis, Mat Disney, Jose Gómez-dans, Martin John Wooster, Bernard Pinty, david roy
These tend to use thermal and/or optical observations to denote an area as being affected by fire if, for instance, the thermal signature is high or the reflectance in near infrared (NIR) or middle infrared  ...  This in turn generally implies that the observations will be taken under varying viewing and/or illumination geometries.  ...  area index (LAI) and information on tree leaf angle distribution (LAD); (from the downward photography) understorey vegetation cover, LAI and LAD, as well as canopy gap probability i.e. the probability  ... 
doi:10.6084/m9.figshare.19657785.v1 fatcat:sghgq4exljbt7nlza37ghg34su

Remote sensing of forest pest damage: a review and lessons learned from a Canadian perspective

R.J. Hall, G. Castilla, J.C. White, B.J. Cooke, R.S. Skakun
2016 Canadian Entomologist  
Current methods to monitor damage by these pests involve both field and aerial surveys.  ...  defoliators) and the damage they cause, a synthesis of the literature involving aerial survey and remote sensing, and a discussion of how these two approaches could be integrated into future pest monitoring from  ...  Hall), Joost van der Sanden, Alice Deschamps, Robert Landry, and Lori White from CCRS.  ... 
doi:10.4039/tce.2016.11 fatcat:ejywzvrdo5fshjxjeesx46vyo4

Estimation of photosynthetic light-use efficience from automated multi-angular spectroradiometer measurements of coastal Douglas-fir

Thomas Hilker
On local scales, GPP can be assessed from measuring CO₂ exchange above the plant canopy using tower-based eddy covariance (EC) systems.  ...  Global modeling of gross primary production (GPP) is a critical component of climate change research.  ...  ACKNOWLEDGEMENTS This research was partly funded by a postgraduate scholarship of the German Academic exchange service (DAAD) to myself and a NSERC Discovery grant to N. Coops.  ... 
doi:10.14288/1.0066755 fatcat:okekjlfilvcsjlmp3k4sq3d6my

An overview of MATISSE-v2.0

Luc Labarre, Karine Caillault, Sandrine Fauqueux, Claire Malherbe, Antoine Roblin, Bernard Rosier, Pierre Simoneau, Karin Stein, John D. Gonglewski
2010 Optics in Atmospheric Propagation and Adaptive Systems XIII  
The aim of this investigation was to develop solid lipid nanoparticles (SLNs) and nanostructured lipid carriers (NLC) loaded green tea extract by using a modified high shear homogenization technique and  ...  We comment on the scope and limitations of the technique and on the optimization of measurement conditions towards specific DNA samples.  ...  Extract the spectra data from MODIS and converts them to NDVI, compared with the leaf area index (LAI) in si-to observation.  ... 
doi:10.1117/12.868183 fatcat:5anlqspzzzcftfufaxvlr45zve

SuperSites Vegetation Monitoring Protocols v1 [article]

Mirko Karan
for overcast images and the blueness index for clear sky images.  ...  clear sky images.  ... 
doi:10.4227/05/56134c1310f16 fatcat:oqllhjdld5fdzk5iante5kid5e

The current state of Białowieża Forest based on the results of the LIFE+ ForBioSensing project [article]

Krzysztof Stereńczak, Damian Korzybski, Rafał Paluch, Andrzej Boczoń, Agata Sałachewicz, Stanisław Miścicki, Łukasz Kuberski, Kamil Pilch, Żaneta Piasecka, Ewa Zin, Dorota Dobrowolska, Marcin Klisz (+14 others)
2022 Zenodo  
The area of the Białowieża Forest has always been an object intensively used by science.  ...  Additionally, this type of data was intended to provide a reference point for analysing the condition of Białowieża Forest in subsequent decades using new methods of data analysis and interpretation.  ...  We thank Rafał Paluch for coordinating the team from the Department of Natural Forests in Białowieża.  ... 
doi:10.5281/zenodo.6559266 fatcat:5owbkiqmyjbzvesozjbjhvvg2q

An Overview of Global Leaf Area Index (LAI): Methods, Products, Validation, and Applications

Hongliang Fang, Frédéric Baret, Stephen Plummer, Gabriela Schaepman-Strub
Leaf area index (LAI) is a critical vegetation structural variable and is essential in the feedback of vegetation to the climate system.  ...  Abstract Leaf area index (LAI) is a critical vegetation structural variable and is essential in the feedback of vegetation to the climate system.  ...  A thresholding process is necessary to separate the foliage from the soil background (downward view) or the sky (upward view).  ... 
doi:10.5167/uzh-182535 fatcat:a3vubhwgtjg3nj24xg4t5hpdqe

The spectroscopy dataset lifecycle: best practice for exchange and dissemination

Laurie Chisholm, Andreas Hueni
When data is created, published, exported, imported, transformed and shared by different parties and used for different purposes, these actions form a data lifecycle.  ...  In today's information age, spectroscopy data management is a significant consideration for researchers and practitioners presenting challenges imposed by multi-disciplinary data producing activities.  ...  are thanked for input and provision of data sets: Jasmine Rickards (ABARES), Andrew Edwards ( Acknowledgements Significant input to the hyper-spectral data acquisition and processing was provided by  ... 
doi:10.5167/uzh-113209 fatcat:wggoexb5dvb2db62zenlaznnza

Vegetation spectroscopy

Lola Suarez, Natalia Restrepo-Coupe, Andreas Hueni, Laurie Chisholm
are thanked for input and provision of data sets: Jasmine Rickards (ABARES), Andrew Edwards ( Acknowledgements Significant input to the hyper-spectral data acquisition and processing was provided by  ...  Measurements can be collected under a variety of sky conditions.  ...  Hemispherical photography is useful when investigating canopy geometry and Leaf Area Index (LAI).  ... 
doi:10.5167/uzh-113211 fatcat:gqg2xsqnxrdenltllsyfwdwvx4

Scaling leaf area index and rainfall interception in lodgepole pine

Brendan Brabender
., maps, drawings, charts) are reproduced by sectioning the original, beginning at the upper left-hand comer and continuing from left to right in equal sections with small overlaps.  ...  The LAI-2000 underestimates true LAI when measurements are taken under sunlit conditions because of illumination o f foliage elements (causing leaves to appear brighter than the sky) and due to an increase  ...  The foliage is black (only sky radiation is seen by the sensor beneath the canopy, since radiation striking foliage is absorbed) 2. The foliage is randomly distributed in the canopy, 3.  ... 
doi:10.7939/r3-zm9m-nf56 fatcat:bmkrdrsgojh2vi2nl72lxa7wru
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