Modeling maize above-ground biomass based on machine learning approaches using UAV remote-sensing data

Table 5 Definitions of three plant height-related metrics this study used for biomass estimation

Variable	Formula (method)	Description	References
CRR	\({\text{CRR}} = \frac{{PH_{{mean}} - PH_{{10\% {\text{min}}}} }}{{PH_{{10\% {\text{max}}}} - PH_{{10\% {\text{min}}}} }}\)	Metric to describe the relative shape of the canopy in forestry studies	[19, 20]
PHkri	kernel thinning and Kriging spatial interpolation	Plant-height metric
BIOVP	\({\text{BIOVP}} = \sum\nolimits_{{\text{i}}}^{{\text{N}}} {S*PH_{{\text{i}}} }\)	Volume metric to estimate crop biomass within certain spatial ranges

ISSN: 1746-4811