Plate 6. Fluorescent NOM preserved in a stalagmite to form annual laminae. This picture shows
annual cycles of NOM fluorescence associated with seasonal groundwater recharge. Stalagmite is
ER-77 from Ernesto Cave, Italy. (Photograph courtesy of Ian Fairchild, Birmingham.)
Emission Wavelength (nm)
B T
T
A T
280
200
400
0
1000
Excitation Wavelength (nm)
500
Optical
Brighteners
Plate 7. Fluorescence excitation–emission matrices (EEMs) for raw sewage where BT = tyrosinelike, T and A T = tryptophan-like fluorescence. (Adapted from Henderson et al., 2009, with permission
from Elsevier.)