Sources and classification of parallel factor components.

Component	E x max (nm)	E m max (nm)	Composition	Matching literature
C1	230	424	Terrestrial HA	C1-Walker et al.51
			UV region FA	C1-Ryan et al.52
			Terrestrial humic substance	C1-Panettieri et al.53
			Humic substance	C1-Amaral et al.54
C2	270	438	Humic substance	C1-Smith et al.55
			Terrestrial HA	C1-Wauthy et al.56
			Humic substance	C2-Eder et al.57
C3	275	500	Humic substance	C1-Lambert et al.58
			Soil yellow HA	C4-Huguet et al.59
			Terrestrial HA	C3-Murphy et al.60