Study on Water Quality Inversion Model of Dianchi Lake Based on Landsat 8 Data

Table 6

Fitting model of COD concentration.

Factor	Model	R ^2	Functional relation
B5	Linear logarithm	0.818	y = 0.036x + 1.9692
B2	Linear logarithm	0.739	y = 0.0368x − 5.8195
B2 + B5	Linear logarithm	0.828	y = 0.0194x − 2.5423
B4 + B5	Linear logarithm	0.666	y = 0.0179x − 1.8273
B5/B2	Cubic	0.679	y = 124.86x3 − 143.9x2 + 69.475x − 5.4311
(B2 − B5)/(B2 + B5)	Cubic	0.680	y = −235.2x3 + 322.04x2 − 158.7x + 34.705