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• W3042854295 endingPage "111985" @default.
• W3042854295 startingPage "111985" @default.
• W3042854295 abstract "Leaf chlorophyll content (LCC), as an important indicator of photosynthetic capacity and nitrogen status, has been non-destructively estimated from canopy reflectance spectra in recent studies. They have also found significant canopy structure and solar angle effects on canopy reflectance spectra, especially for row-structured open crop canopies with varying sunlit and shaded soil backgrounds over seasonal and diurnal cycles. Since the canopy reflectance signature of crops is negligibly contaminated by shaded soil, it can be inferred that LCC should be better estimated when the soil background is under shaded conditions than under sunlit conditions. However, the effects of solar angle or spectral observation time and canopy structure on LCC estimation for row crops have been poorly understood. This study aimed to determine the optimal observation time and to reduce the canopy structural effect for LCC estimation over row-structured crops. To achieve these goals, we simulated canopy reflectance spectra covering four typical crop orientations over seasonal and diurnal cycles based on the leaf optical models (PROSPECT-5B and PROSPECT-D) coupled with canopy radiative transfer models (4SAIL and 4SAIL-RowCrop). Moreover, this study proposed the leaf area index (LAI)-insensitive chlorophyll index (LICI) to mitigate the canopy structural effect on the LCC ~ LICI relationship. LICI and 11 traditional vegetation indices (VIs) were investigated to calibrate semi-empirical LCC ~ VI models with canopy spectral simulations. The performance of those models in LCC estimation was evaluated with experimental datasets measured from both ground and unmanned aerial vehicle (UAV) platforms. Our results showed linear relationships between LICI and LCC for both synthetic and experimental datasets and negligible sensitivity of those models to LAI. Compared to traditional spectral measurements around 12:00 h, LCC estimation could be improved at observation time (15:00 h) that minimized observed sunlit soil fraction for the north-south (NS) row crop orientation. The semi-empirical LCC ~ LICI model (LCC = 52.85 × LICI - 16.71) calibrated with the combination of PROSPECT-D and 4SAIL-RowCrop showed the best accuracies among all VIs, with root mean square error (RMSE) values of 5.01 μg/cm2 and 3.32 μg/cm2 for ground-based and UAV-based canopy spectra measured at 15:00 h, respectively. For the commonly used NS row orientation, this study recommends off-noon spectral measurements to avoid the exposure of sunlit soil to the sensor. These findings have great potential for improving the understanding of the canopy structure and solar angle effects on LCC estimation and facilitating the spectral sampling protocols for crop chlorophyll status monitoring." @default.
• W3042854295 created "2020-07-23" @default.
• W3042854295 creator A5000071336 @default.
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• W3042854295 date "2020-10-01" @default.
• W3042854295 modified "2023-10-15" @default.
• W3042854295 title "Improved estimation of leaf chlorophyll content of row crops from canopy reflectance spectra through minimizing canopy structural effects and optimizing off-noon observation time" @default.
• W3042854295 cites W1703267963 @default.
• W3042854295 cites W1944729816 @default.
• W3042854295 cites W1966675249 @default.
• W3042854295 cites W1967476626 @default.
• W3042854295 cites W1969010087 @default.
• W3042854295 cites W1971959280 @default.
• W3042854295 cites W1973397255 @default.
• W3042854295 cites W1978160572 @default.
• W3042854295 cites W1979943149 @default.
• W3042854295 cites W1983279516 @default.
• W3042854295 cites W1986930621 @default.
• W3042854295 cites W1988269748 @default.
• W3042854295 cites W1995029758 @default.
• W3042854295 cites W2000485836 @default.
• W3042854295 cites W2001948755 @default.
• W3042854295 cites W2005908679 @default.
• W3042854295 cites W2007939589 @default.
• W3042854295 cites W2028210471 @default.
• W3042854295 cites W2028724344 @default.
• W3042854295 cites W2029118156 @default.
• W3042854295 cites W2030106896 @default.
• W3042854295 cites W2036003376 @default.
• W3042854295 cites W2037402536 @default.
• W3042854295 cites W2046404820 @default.
• W3042854295 cites W2049556619 @default.
• W3042854295 cites W2051128904 @default.
• W3042854295 cites W2052906539 @default.
• W3042854295 cites W2055842947 @default.
• W3042854295 cites W2057084393 @default.
• W3042854295 cites W2066612219 @default.
• W3042854295 cites W2068195262 @default.
• W3042854295 cites W2070203790 @default.
• W3042854295 cites W2074349517 @default.
• W3042854295 cites W2091493105 @default.
• W3042854295 cites W2093846586 @default.
• W3042854295 cites W2101010747 @default.
• W3042854295 cites W2104776848 @default.
• W3042854295 cites W2107682396 @default.
• W3042854295 cites W2109006150 @default.
• W3042854295 cites W2111370427 @default.
• W3042854295 cites W2111947859 @default.
• W3042854295 cites W2114753915 @default.
• W3042854295 cites W2120580365 @default.
• W3042854295 cites W2124937378 @default.
• W3042854295 cites W2128438912 @default.
• W3042854295 cites W2129032375 @default.
• W3042854295 cites W2129483042 @default.
• W3042854295 cites W2129719999 @default.
• W3042854295 cites W2132926714 @default.
• W3042854295 cites W2137608957 @default.
• W3042854295 cites W2144023308 @default.
• W3042854295 cites W2145669224 @default.
• W3042854295 cites W2153243519 @default.
• W3042854295 cites W2156468842 @default.
• W3042854295 cites W2157760685 @default.
• W3042854295 cites W2163410149 @default.
• W3042854295 cites W2165916356 @default.
• W3042854295 cites W2171878269 @default.
• W3042854295 cites W2202464059 @default.
• W3042854295 cites W2248139498 @default.
• W3042854295 cites W2288553003 @default.
• W3042854295 cites W2319146745 @default.
• W3042854295 cites W2527638819 @default.
• W3042854295 cites W2529670104 @default.
• W3042854295 cites W2539185528 @default.
• W3042854295 cites W2551562355 @default.
• W3042854295 cites W2565157507 @default.
• W3042854295 cites W2596051487 @default.
• W3042854295 cites W2613366256 @default.
• W3042854295 cites W2621112468 @default.
• W3042854295 cites W2751022621 @default.
• W3042854295 cites W2770928509 @default.
• W3042854295 cites W2770955947 @default.
• W3042854295 cites W2775006744 @default.
• W3042854295 cites W2782772130 @default.
• W3042854295 cites W2801669777 @default.
• W3042854295 cites W2859848446 @default.
• W3042854295 cites W2883847543 @default.
• W3042854295 cites W2884438462 @default.
• W3042854295 cites W2889339523 @default.
• W3042854295 cites W2896845224 @default.

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