Results 11 to 20 of about 510 (196)
Remote Sensing, 2020 Estimating leaf area index (LAI) and assessing spatial variation in LAI across a landscape is crucial to many ecological studies. Several direct and indirect methods of LAI estimation have been developed and compared; however, many of these methods are ...
Tamara E. Rudic +2 more
doaj +4 more sources
Agricultural and Forest Meteorology, 2005 The retrieval of canopy architectural parameters using off-the-shelf digital cameras with fish-eye lens is investigated. The technique used takes advantage of the sensor’s linear response to light of these cameras to improve the estimation of gap fraction using:
Jing Chen, Richard Fernandes
exaly +3 more sources
ISPRS Journal of Photogrammetry and Remote Sensing, 2019 Leaf inclination plays a crucial role in regulating the radiation, carbon and water fluxes in plant canopies. Accurate measurement of the probability density function of leaf inclination (i.e., the leaf angle distribution or leaf inclination distribution function (LIDF)), is very important for modelling photosynthesis as well as measuring leaf area ...
Jing Liu, Tiejun Wang, Simon Jones
exaly +3 more sources
Potential of Automated Digital Hemispherical Photography and Wireless Quantum Sensors for Routine Canopy Monitoring and Satellite Product Validation [PDF]
2021 IEEE International Geoscience and Remote Sensing Symposium IGARSS, 2021 To better characterize the temporal dynamics of vegetation biophysical variables, a variety of automated in situ measurement techniques have been developed in recent years. In this study, we investigated automated digital hemispherical photography (DHP) and wireless quantum sensors, which were installed at two sites under the Copernicus Ground Based ...
Luke A. Brown +14 more
openaire +2 more sources
Estimating Effective Leaf Area Index of Winter Wheat Based on UAV Point Cloud Data
Drones, 2023 Leaf area index (LAI) is a widely used plant biophysical parameter required for modelling plant photosynthesis and crop yield estimation. UAV remote sensing plays an increasingly important role in providing the data source needed for LAI extraction. This
Jie Yang +7 more
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Methods in Ecology and Evolution, 2023 Digital hemispherical photography (DHP) is widely used to derive forest biophysical variables including leaf, plant, and green area index (LAI, PAI and GAI), the fraction of intercepted photosynthetically active radiation (FIPAR), and the fraction of ...
Luke A. Brown +7 more
doaj +1 more source
Ecological Indicators, 2021 Automatic and accurate measurements of the leaf area index (LAI) can provide information about key parameters of vegetation structure in an ecosystem. Little attention, however, has been paid to LAI dynamics for shrub canopies in both arid and semiarid ...
Xiaotao Niu +5 more
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IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing, 2021 To further progress the validation of global leaf area index (LAI) products, temporally continuous reference data are a key requirement, as periodic field campaigns fail to adequately characterize temporal dynamics.
Luke A. Brown +4 more
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TRACKING FOREST AND OPEN AREA EFFECTS ON SNOW ACCUMULATION BY UNMANNED AERIAL VEHICLE PHOTOGRAMMETRY [PDF]
The International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences, 2016 Airborne digital photogrammetry is undergoing a renaissance. The availability of low-cost Unmanned Aerial Vehicle (UAV) platforms well adopted for digital photography and progress in software development now gives rise to apply this technique to ...
T. Lendzioch, J. Langhammer, M. Jenicek
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iForest - Biogeosciences and Forestry, 2014 Proximal sensing methods using digital photography have gained wide acceptance for describing and quantifying canopy properties. Digital hemispherical photography (DHP) is the most widely used photographic technique for canopy description.
Chianucci F, Chiavetta U, Cutini A
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