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Fig. 149: Architecture of the Model

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Abbreviations

Abbreviations

for spectrum generation. Æ Satellite data- (CHRIS) acquired (24/9/2017) for the second field trip had 70% cloud. Since there is no alternative data that matches with this field inventory, the same data was used after removing the cloud from CHRIS data using the mono-regression method. The values were replaced using the Sentinel data of the same date. Æ The data (cloud-free) relating to the field – 3 was acquired on 24-05-2018. Æ Noise removal, and atmospheric and geometric correction processes were conducted using scripting and regular expressions for all three seasons. Æ An interface was made for the leaf upscaling using a new approach. The input parameters were biochemical values of the leaf species from the lab and on-field parameters (primary being leaf spectrum) which is upscaled to canopy level and then the spectrum is recreated concerning the upscaled biochemical parameters.

Species Canopy upscaling

Æ The model considers leaf spectra along with derived canopy properties in estimating canopy spectra.

The canopy spectrum starts at 400nm. Æ It is considered that 480 nm – 750 nm is the chlorophyll retrieval region; 376nm-406nm, 1300nm1450nm, 1778nm – 1949nm are water absorption regions; 1700nm to 1750nm is for nitrogen retrieval, 2100nm – 2300nm is for lignin and cellulose absorption retrieval together. Æ In general, the water absorption bands are considered from 1300nm – 1450nm, but water can affect the 376nm-406nm region due to their presence in leaf pigments; and the the1778nm-1949nm region due to the presence of protein and nitrogen. Æ The canopy level estimates of selected biophysical and biochemical parameters were integrated to result in canopy-level spectra using a semi-analytical search-based expert knowledge-driven polynomial modelling, considering the spectral sensitivity of canopy parameters across the optical, and electromagnetic spectrum. Æ While upscaling, parametric regression is applied to a few spectral bands to maintain the pattern of the spectrum.

Fig. 149: Architecture of the Model

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