Table 2. Equations used to calculate vegetation indices.

Indices	Formula	References
NDVI	(R800* – R670)/(R800 + R670)	Tucker (1979)
EVI	2.5 × ((R800 − R670)/(R800 + 6 × R670 − 7.5 × R470 + 1))	Huete et al. (2002)
PRI	(R570 − R531)/(R531 + R570)	Gamon, Peñuelas & Field (1992)
NDWI	(R860 − R1,240)/(R860 − R1,240)	Gao (1996)
mNDWI	(R1,280 − R1,450)/(R1,280 + R1,450)	Xu (2006)

Note:

^*The R₄₇₀, R₅₃₁, R₅₇₀, R₆₇₀, R₈₀₀, R₈₆₀, R_1,240, and R_1,450 represent the reflectance values at 470, 531, 570, 670, 800, 860, 1,240, and 1,450 nm, respectively.