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Estimating chlorophyll content from hyperspectral vegetation indices: Modeling and validation

Chaoyang Wu, Zheng Niu, Quan Tang, Wenjiang Huang
2008 Agricultural and Forest Meteorology  
Recent studies have demonstrated the feasibility of retrieval of chlorophyll content from hyperspectral vegetation indices composed by the reflectance of specific bands.  ...  to leaf area index (LAI) variations by taking into account the effect of quick saturation at 670 nm with relatively low chlorophyll content.  ...  Also we are very grateful for the critical comments of anonymous reviewers.  ... 
doi:10.1016/j.agrformet.2008.03.005 fatcat:rary2r2pibc2xmjh6hmgs4plje

Inverting the PROSAIL canopy reflectance model using neural nets trained on streamlined databases

Clement Atzberger
2010 Journal of Spectral Imaging  
The main drawbacks of these The widely used PROSAIL radiative transfer model was coupled with a simple soil reflectance parameterisation to estimate the leaf area index (LAI) of winter wheat (Triticum  ...  To avoid time-consuming numerical optimisations, a neural net (NN) was used for model inversion. The NN was trained on 3000 spectral patterns generated by the reflectance model.  ...  The access to the wheat fields accorded by the land owners is also acknowledged. The research was partly funded by DfG through SfB 522 "umwelt und region".  ... 
doi:10.1255/jsi.2010.a2 fatcat:gcpfb64ny5gkjkc4opohooh2j4

Use of spectral pre-processing methods to compensate for the presence of packaging film in visible–near infrared hyperspectral images of food products

A. Gowen, G. Downey, C. Esquerre, C. O'Donnell
2010 Journal of Spectral Imaging  
The main drawbacks of these The widely used PROSAIL radiative transfer model was coupled with a simple soil reflectance parameterisation to estimate the leaf area index (LAI) of winter wheat (Triticum  ...  To avoid time-consuming numerical optimisations, a neural net (NN) was used for model inversion. The NN was trained on 3000 spectral patterns generated by the reflectance model.  ...  The access to the wheat fields accorded by the land owners is also acknowledged. The research was partly funded by DfG through SfB 522 "umwelt und region".  ... 
doi:10.1255/jsi.2010.a1 fatcat:j3zw7m6vyjgqrdw4gzwomzeep4

Drought Stress and the Need for Drought Stress Sensing in a World of Global Climate Change [chapter]

Rita Linke
2012 Irrigation Systems and Practices in Challenging Environments  
The shape of leaf reflectance spectra is determined by the absorption of leaf pigments, mainly chlorophyll.  ...  Fig. 1 . 1 Reflectance spectra of leaves from irrigated and rainfed grown Triticum asetivum L. Abbreviations: Chl: chlorophyll content, RWC: relative water content.  ...  Topics range from effects of irrigation on the physiology of plants, deficit irrigation practices and the genetic manipulation, to creating drought tolerant variety and a host of interesting topics to  ... 
doi:10.5772/31485 fatcat:4jj2yqulyfe5nhbaclx2kmsuzi

Field Measurements of Canopy Spectra for Biomass Assessment of Small-Grain Cereals [chapter]

Conxita Royo, Dolors Villegas
2011 Biomass - Detection, Production and Usage  
content of the soil.  ...  Sensor position The angles between sun, sensor and canopy surface may lead to the appearance of shadow or soil background in the field of view of the apparatus, causing disturbing effects in the spectra  ...  .), ISBN: 978-953-307-492-4, InTech, Available from: http://www.intechopen.com/books/biomass-detection-production-andusage/field-measurements-of-canopy-spectra-for-biomass-assessment-of-small-grain-cereals  ... 
doi:10.5772/17745 fatcat:7sjg3t4wdnbvbkz4fixu4cswsa

Inversion of a radiative transfer model for estimating vegetation LAI and chlorophyll in a heterogeneous grassland

Roshanak Darvishzadeh, Andrew Skidmore, Martin Schlerf, Clement Atzberger
2008 Remote Sensing of Environment  
The widely used PROSAIL model was inverted with canopy spectral reflectance measurements by means of a look-up table (LUT).  ...  Of the three investigated plant characteristics, canopy chlorophyll content was estimated with the highest accuracy (R 2 = 0.70, NRMSE = 0.18).  ...  Istiak Sobhan for their assistance during the field campaign. The comments of the two anonymous reviewers have been very helpful in improving the manuscript.  ... 
doi:10.1016/j.rse.2007.12.003 fatcat:wwx3v2qrlbamngqhmehvr5zkti

Deriving green crop area index and canopy chlorophyll density of winter wheat from spectral reflectance data

N.H Broge, J.V Mortensen
2002 Remote Sensing of Environment  
They have generally been developed as an attempt to reduce spectral effects caused by external factors such as the atmosphere and the soil background.  ...  Green crop area index (GCAI) and canopy chlorophyll density (CCD) were the major variables determined from the biophysical data set.  ...  Acknowledgments This work was carried out as part of the Danish Multisensor Airborne Campaign (DANMAC) project funded by the Danish Research Councils.  ... 
doi:10.1016/s0034-4257(01)00332-7 fatcat:vwnrs3ffmnf7lkuruhzy4ns75m

Estimating the Leaf Nitrogen Content with a New Feature Extracted from the Ultra-High Spectral and Spatial Resolution Images in Wheat

Jiale Jiang, Jie Zhu, Xue Wang, Tao Cheng, Yongchao Tian, Yan Zhu, Weixing Cao, Xia Yao
2021 Remote Sensing  
Proximal sensing is the most common technique for monitoring crop traits, but it is often influenced by soil background and shadow effects.  ...  However, few studies have investigated the classification of different components of crop canopy, and the performance of spectral and textural indices from different components on estimating leaf nitrogen  ...  Conflicts of Interest: The authors declare no conflict of interest.  ... 
doi:10.3390/rs13040739 fatcat:mpbcdm6y5zh7bnfl2ojhl6ibim

Calibration and validation of hyperspectral indices for the estimation of broadleaved forest leaf chlorophyll content, leaf mass per area, leaf area index and leaf canopy biomass

G LEMAIRE, C FRANCOIS, K SOUDANI, D BERVEILLER, J PONTAILLER, N BREDA, H GENET, H DAVI, E DUFRENE
2008 Remote Sensing of Environment  
This article aims at finding efficient hyperspectral indices for the estimation of forest sun leaf chlorophyll content (CHL, µg cm leaf − 2 ), sun leaf mass per area (LMA, g dry matter m leaf − 2 ), canopy  ...  The method is based on the determination of the best vegetation indices (index form and wavelengths) using the radiative transfer model PROSAIL (formed by the newly-calibrated leaf reflectance model PROSPECT  ...  This work was also supported by the GIP-Ecofor and ORE F-ORE-T. We would like to thank the anonymous reviewers for their valuable comments and constructive feedback.  ... 
doi:10.1016/j.rse.2008.06.005 fatcat:dz4wk2erujdtlafhzexrh6wpm4

Modelling the spectral response of the desert tree Prosopis tamarugo to water stress

R.O. Chávez, J.G.P.W. Clevers, M. Herold, M. Ortiz, E. Acevedo
2013 International Journal of Applied Earth Observation and Geoinformation  
Observed variation in reflectance during the day (due to leaf movements) as well as changes over the experimental period (due to water stress) were successfully modelled by using the Soil-Leaf-Canopy (  ...  Diurnal leaf movements observed in Tamarugo plants (as adaptation to decrease direct solar irradiation at the hottest time of the day) had an important effect on canopy reflectance and were explained by  ...  Acknowledgements This work has been supported by CONICYT-Chile and Wageningen University. The authors would like to thank CONAF-Chile for the donation of plants for the experiment; to P. Silva, C.  ... 
doi:10.1016/j.jag.2012.08.013 fatcat:txpisnuidrh2nb7jfvrqqxgciq

CEFLES2: the remote sensing component to quantify photosynthetic efficiency from the leaf to the region by measuring sun-induced fluorescence in the oxygen absorption bands

U. Rascher, G. Agati, L. Alonso, G. Cecchi, S. Champagne, R. Colombo, A. Damm, F. Daumard, E. de Miguel, G. Fernandez, B. Franch, J. Franke (+29 others)
2009 Biogeosciences Discussions  
The aim of this campaign was to test if fluorescence signal detected from an airborne platform can be used to improve estimates of plant mediated exchange on the mesoscale.  ...  It was combined with extensive ground-based quantification of leaf-and canopy-level processes in support of ESA's Candidate Earth Explorer Mission of the "Fluorescence Explorer" (FLEX).  ...  This work has been made possible by the funding support of the ESA-projects (1)  ... 
doi:10.5194/bgd-6-2217-2009 fatcat:nrhssjfvpre5hpivq4apao5hsi

CEFLES2: the remote sensing component to quantify photosynthetic efficiency from the leaf to the region by measuring sun-induced fluorescence in the oxygen absorption bands

U. Rascher, G. Agati, L. Alonso, G. Cecchi, S. Champagne, R. Colombo, A. Damm, F. Daumard, E. de Miguel, G. Fernandez, B. Franch, J. Franke (+29 others)
2009 Biogeosciences  
CEFLES2: the remote sensing component to quantify photosynthetic efficiency from the leaf to the region by measuring sun-induced fluorescence in the oxygen absorption bands Rascher,  ...  This work has been made possible by the funding support of the ESA-projects (1)  ...  It can be seen that leaves with the same chlorophyll content can show different emission spectra ( Fig. 4 ; e.g. wheat and bean).  ... 
doi:10.5194/bg-6-1181-2009 fatcat:smoddtodobftxmzbyoroscpv4e

Retrieving LAI, chlorophyll and nitrogen contents in sugar beet crops from multi-angular optical remote sensing: Comparison of vegetation indices and PROSAIL inversion for field phenotyping

Sylvain Jay, Fabienne Maupas, Ryad Bendoula, Nathalie Gorretta
2017 Field crops research (Print)  
On the other hand, the estimation of leaf-level quantities is less accurate, the best accuracy being obtained for leaf chlorophyll content estimation based on VIs ( = 17 %).  ...  Overall, both approaches are promising to remotely estimate LAI and canopy chlorophyll content ( ≤ 10 %). In addition, VIs show a great potential to retrieve canopy nitrogen content ( = 10 %).  ...  Acknowledgments This study was funded by the French Ministry of Agriculture, Agrifood, and Forestry (PHENOBET  ... 
doi:10.1016/j.fcr.2017.05.005 fatcat:ipriw2wcsjg5bpxhfu2stqitya

Prediction of Wheat Yield Using Spectral Reflectance Indices Under Different Tillage, Residue and Nitrogen Management Practices

Sujan Adak, K. K. Bandyopadhyay, R. N. Sahoo, N. Mridha, M. Shrivastava, T. J. Purakayastha
2021 Current Science  
Effect of tillage, residue mulch and nitrogen management on canopy spectral reflectance indices and their potential to predict the grain and biomass yield of wheat in advance were studied in a field experiment  ...  The canopy reflectance was measured using a hand-held ASD FieldSpec spectroradiometer at booting, milking and dough stage of wheat.  ...  The logistic support received from the Director, Indian Agricultural Research Institute, New Delhi is acknowledged.  ... 
doi:10.18520/cs/v121/i3/402-413 fatcat:67xx2fm7kndqnnlkdl4vjqwnau

Extraction of Sensitive Bands for Monitoring the Winter Wheat (Triticum aestivum) Growth Status and Yields Based on the Spectral Reflectance

Chao Wang, Meichen Feng, Wude Yang, Guangwei Ding, Lujie Xiao, Guangxin Li, Tingting Liu, Wujun Ma
2017 PLoS ONE  
The crop variables including aboveground biomass (AGB), soil and plant analyzer development (SPAD) value, yield, and canopy spectra were determined.  ...  To extract the sensitive bands for estimating the winter wheat growth status and yields, field experiments were conducted.  ...  We thank the support of Zhihua Li for her help in measuring the ground biomass of winter wheat.  ... 
doi:10.1371/journal.pone.0167679 pmid:28060827 pmcid:PMC5218389 fatcat:cacewebay5fhbdjjzh3covifcy
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