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A Transformed Triangular Vegetation Index for Estimating Winter Wheat Leaf Area Index

Naichen Xing, Wenjiang Huang, Qiaoyun Xie, Yue Shi, Huichun Ye, Yingying Dong, Mingquan Wu, Gang Sun, Quanjun Jiao
2019 Remote Sensing  
In this study, we proposed a new index for LAI retrieval-transformed triangular vegetation index (TTVI), which replaces NIR and red bands of triangular vegetation index (TVI) into NIR and red-edge bands  ...  Leaf area index (LAI) is a key parameter in plant growth monitoring. For several decades, vegetation indices-based empirical method has been widely-accepted in LAI retrieval.  ...  Acknowledgments: The authors would like to thank Xianfeng Zhou, Huiqin Ma, Linyi Liu, Weiping Kong for collecting the field measurement data at Beijing Shunyi District.  ... 
doi:10.3390/rs12010016 fatcat:aheomjfmozdihepmznvfi7p254

Joint Retrieval of Winter Wheat Leaf Area Index and Canopy Chlorophyll Density Using Hyperspectral Vegetation Indices

Naichen Xing, Wenjiang Huang, Huichun Ye, Yu Ren, Qiaoyun Xie
2021 Remote Sensing  
Leaf area index (LAI) and canopy chlorophyll density (CCD) are key biophysical and biochemical parameters utilized in winter wheat growth monitoring.  ...  The second method is to create a transformed triangular vegetation index (TTVI2) based on the spectral and physiological characteristics of the parameters.  ...  Our thanks are also extended to the editors and the two reviewers for their valuable suggestions. Conflicts of Interest: The authors declare no conflict of interest.  ... 
doi:10.3390/rs13163175 fatcat:2qa23prmzjct3gfeb5tppppglq

A New Integrated Vegetation Index for the Estimation of Winter Wheat Leaf Chlorophyll Content

Cui, Zhao, Huang, Song, Ye, Zhou
2019 Remote Sensing  
However, many published vegetation indices are sensitive to crop canopy structure, especially the leaf area index (LAI), when crop canopy spectra are used.  ...  This index has strong potential for monitoring winter wheat nitrogen status and precision nitrogen management.  ...  First, fresh winter wheat leaf samples from a certain area in each plot were mixed with a given volume of 80% alcohol solution.  ... 
doi:10.3390/rs11080974 fatcat:ug24whrd5fdy3nepwbz3pox7yi

Estimating Wheat Shoot Nitrogen Content at Vegetative Stage from In Situ Hyperspectral Measurements

Yansong Bao, Kang Xu, Jinzhong Min, Jianjun Xu
2013 Crop science  
index; GNDVI, green normalized difference vegetation index; LDW, leaf dry weight; LNC, leaf N content; MCARI, modified chlorophyll absorption in reflectance index; NDNI, normalized difference N index;  ...  , stem dry weight; SNC, shoot N content; STNC, stem N content; TAP, total amount of plants; VIopt, optimal vegetation index.  ...  Sembiring et al. (1998) used normalized difference vegetation index (NDVI) to predict N uptake for winter wheat and concluded that NDVI was a good index to N uptake.  ... 
doi:10.2135/cropsci2013.01.0012 fatcat:xkm6paejv5alphwwqdua3vmnq4

Estimating plant area index for monitoring crop growth dynamics using Landsat-8 and RapidEye images

Jiali Shang, Jiangui Liu, Ted Huffman, Budong Qian, Elizabeth Pattey, Jinfei Wang, Ting Zhao, Xiaoyuan Geng, David Kroetsch, Taifeng Dong, Nicholas Lantz
2014 Journal of Applied Remote Sensing  
Plant area index (PAI) was measured at different growth stages using digital hemispherical photography at two corn fields, two winter wheat fields, and two soybean fields.  ...  The study was carried out in southern Ontario, Canada, during the 2013 growing season for three annual crops, corn, soybeans, and winter wheat.  ...  Acknowledgments This study was funded by Agriculture and Agri-Food Canada and the Canadian Space Agency through a research project on land productivity using Earth observation and crop modeling.  ... 
doi:10.1117/1.jrs.8.085196 fatcat:fq47wzijznbfrmdkpsw3fpsupi

Evaluation of RapidEye vegetation indices for prediction of biophysical/biochemical variables of winter wheat

Ilina Kamenova, Petar Dimitrov, Rusina Yordanova
2018 Aerospace Research in Bulgaria  
The aim of the study is to evaluate the possibility for using RapidEye data for prediction of Leaf Area Index (LAI), fraction of Absorbed Photosynthetically Active Radiation (fAPAR), fraction of vegetation  ...  Cover (fCover), leaf Chlorophyll Concentration (CC) and Canopy Chlorophyll Content (CCC) of winter wheat.  ...  Todorova from the co-operative in Trebich for providing access to the fields and to G. Jelev and Y. Naydenov who helped with the fieldwork.  ... 
doi:10.3897/arb.v30.e06 fatcat:paa7lvrqzncj7adrztnfp5xtbu

Evaluating the relationship between biomass, percent groundcover and remote sensing indices across six winter cover crop fields in Maryland, United States

Kusuma Prabhakara, W. Dean Hively, Gregory W. McCarty
2015 International Journal of Applied Earth Observation and Geoinformation  
The triangular vegetation index (TVI) was most accurate in estimating high ranges of biomass (r 2 = 0.86), while NDVI did not experience a clustering of values in the low and medium biomass ranges but  ...  The results of this study show that accounting for index saturation, senescence, and frost burn on leaves can greatly increase the accuracy of estimates of percent groundcover and biomass for winter cover  ...  Antonio Pereira for help with fieldwork and in the laboratory. Additional thanks to Dr. Chris Justice, Dr. Samuel Goward, and Dr. Ralph Dubayah for their guidance on this study.  ... 
doi:10.1016/j.jag.2015.03.002 fatcat:wxo3d4gp5rd53pbb3ro3yb54du

Reflectance estimation of canopy nitrogen content in winter wheat using optimised hyperspectral spectral indices and partial least squares regression

Fei Li, Bodo Mistele, Yuncai Hu, Xinping Chen, Urs Schmidhalter
2014 European Journal of Agronomy  
PLSR will be useful for real-time estimation of N status of winter wheat in the fields and for guiding farmers in the accurate application of their N fertilisation strategies.  ...  The results indicate that PLSR is a potentially useful approach to derive canopy N content of winter wheat across growth stages, cultivars, sites and years under field conditions when a broad set of canopy  ...  Thus, a global model for N estimation in winter wheat for all conditions is probably developed when the spectra and the canopy N content sampling from other cultivars, ecological areas and years are involved  ... 
doi:10.1016/j.eja.2013.09.006 fatcat:jtj6spsgtvhgrp43ttjhzcvqki

UAV-Based Hyperspectral and Ensemble Machine Learning for Predicting Yield in Winter Wheat

Zhen Chen, Qian Cheng, Fuyi Duan, Xiuqiao Huang, Honggang Xu, Ruixiu Sui, Zongpeng Li
2022 Agronomy  
Using growth-stage information to estimate winter wheat yields in a timely manner is essential for accurate crop management and rapid decision-making in sustainable agriculture, and to increase productivity  ...  Winter wheat is a widely-grown cereal crop worldwide.  ...  The ND [553, 682] index can be used to estimate the chlorophyll content and can minimize the effect of shading and leaf area index size [85, 86] .  ... 
doi:10.3390/agronomy12010202 fatcat:nnzjcfeklfb7tne4yhx5eo6ei4

Detection of Powdery Mildew in Two Winter Wheat Plant Densities and Prediction of Grain Yield Using Canopy Hyperspectral Reflectance

Xueren Cao, Yong Luo, Yilin Zhou, Jieru Fan, Xiangming Xu, Jonathan S. West, Xiayu Duan, Dengfa Cheng, Rita Grosch
2015 PLoS ONE  
For the two plant densities, the area of the red edge peak (Σdr 680-760 nm ), difference vegetation index (DVI), and triangular vegetation index (TVI) were significantly correlated negatively with disease  ...  To determine the influence of plant density and powdery mildew infection of winter wheat and to predict grain yield, hyperspectral canopy reflectance of winter wheat was measured for two plant densities  ...  estimating powdery mildew of winter wheat; and (iii) to predict grain yield of wheat using canopy reflectance.  ... 
doi:10.1371/journal.pone.0121462 pmid:25815468 pmcid:PMC4376796 fatcat:ady5w5xk4za4hlfsc7vpguda3y

Remotely Estimating Aerial N Uptake in Winter Wheat Using Red-Edge Area Index From Multi-Angular Hyperspectral Data

Bin-Bin Guo, Yun-Ji Zhu, Wei Feng, Li He, Ya-Peng Wu, Yi Zhou, Xing-Xu Ren, Ying Ma
2018 Frontiers in Plant Science  
areas; DVI, Difference vegetation index; EVI, Enhanced Vegetation Index; LAI, Leaf area index; LNC, Leaf N concentration; LSDR, Left-side peak area; MCARI-1, Modified chlorophyll absorption in reflectance  ...  index; mRER, Modified red-edge ratio; mRPA, Modified right-side peak area index; MSR, Modified simple ratio; mSR705, Modified rededge ratio; MTVI1, Modified triangular vegetation index; N, Nitrogen; NAOC  ...  These include the triangle vegetation index (TVI) and modified TVI for green leaf area index (LAI) (Broge and Leblanc, 2000; Haboudane et al., 2004) ; the red-edge reflectance curve area for green biomass  ... 
doi:10.3389/fpls.2018.00675 pmid:29887871 pmcid:PMC5982994 fatcat:vqxni34b65dq7hfruajvxdutea

Integration of Satellite-Based Optical and Synthetic Aperture Radar Imagery to Estimate Winter Cover Crop Performance in Cereal Grasses

Jyoti S. Jennewein, Brian T. Lamb, W. Dean Hively, Alison Thieme, Resham Thapa, Avi Goldsmith, Steven B. Mirsky
2022 Remote Sensing  
Our results suggest that the integration of the normalized difference red-edge vegetation index (NDVI_RE1; employing Sentinel-2 bands 5 and 8A), combined with SAR interferometric (InSAR) coherence, best  ...  However, these results were season- and species-specific (R2 = 0.74, 0.81, and 0.34; RMSE = 1227, 793, and 776 kg ha−1, for wheat (Triticum aestivum L.), triticale (Triticale hexaploide L.), and cereal  ...  VIs derived from optical imagery, particularly NDVI, tend to saturate at a leaf area index (LAI) greater than three in numerous plant species [23, 24] .  ... 
doi:10.3390/rs14092077 fatcat:udrhu4zdbfb7bbluhmcye7kybe

Assessment of Leaf Chlorophyll Content Models for Winter Wheat Using Landsat-8 Multispectral Remote Sensing Data

Xianfeng Zhou, Jingcheng Zhang, Dongmei Chen, Yanbo Huang, Weiping Kong, Lin Yuan, Huichun Ye, Wenjiang Huang
2020 Remote Sensing  
The results showed that the modified triangular vegetation index (MTVI2) exhibited the best estimate accuracy for LCC retrieval with a root mean square error (RMSE) of 5.99 μg/cm2 and a relative RMSE (  ...  The leaf chlorophyll content (LCC) is a critical index to characterize crop growth conditions, photosynthetic capacity, and physiological status.  ...  This study was also granted by a National special support program for high-level personnel recruitment (Wenjiang Huang) and the Ten-thousand Talents Program (Wenjiang Huang).  ... 
doi:10.3390/rs12162574 fatcat:pdabnyna6zgibm5nebqgjr3lsq

Using Space-borne Hyperspectral Imagery on Mapping Nitrogen Fertilizer Excess to the Environment

2015 International Journal of Science and Research (IJSR)  
The calculation of N nutrition index (NNI) requires destructive sampling and chemical analysis to determine biomass and plant N concentration, which is time and cost consuming and, thus, impractical for  ...  in-season site-specific N management across large areas.  ...  (MTVI2) [13] Red Edge Normalized Difference Vegetation Index (RENDVI) [11] Red Edge Position Index (REPI) [7] Transformed Chlorophyll Absorption Reflectance Index (TCARI) [13] Triangular Vegetation  ... 
doi:10.21275/v4i11.nov151619 fatcat:5x7hyco7dfcxroyswtrr7zglcm

Spectral analysis of winter wheat leaves for detection and differentiation of diseases and insects

Lin Yuan, Yanbo Huang, Rebecca W. Loraamm, Chenwei Nie, Jihua Wang, Jingcheng Zhang
2014 Field crops research (Print)  
Tritici), powdery mildew (Blumeria graminis) and wheat aphid (Sitobion avenae F.) infestation are three serious conditions that have a severe impact on yield and grain quality of winter wheat worldwide  ...  To obtain appropriate bands and spectral features (SFs) for stressor discrimination and damage intensity estimation, a correlation analysis and an independent t-test were used jointly.  ...  Hong Chang for data collection.  ... 
doi:10.1016/j.fcr.2013.11.012 fatcat:4zrrerygyvhhlekxahsj7ptqdm
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