Chemometric Analysis of Organic Matter Fluorescence - Aquatic Organic Matter Fluorescence - page 363

Table 10.2. PLS prediction of DOC concentration from fluorescence intensities
in the Horsens catchment, using separate models for the river and wastewater
samples (n = 302) and estuary samples (n = 211)

River and wastewater Estuary

nLV RMSE cv R 2 cv RMSE cv R 2 cv

1 120.59 0.80 46.51 0.24

2 104.11 0.85 36.57 0.52

3 98.25 0.87 34.51 0.58

4 93.07 0.88 35.53 0.58

5 89.07 0.89 33.21 0.63

6 90.32 0.89 32.49 0.64

7 90.17 0.89 31.48 0.66

Note : The “best model,” representing a trade-off between minimum number of latent vari-
ables (nLV), minimum RMSE cv and maximum R 2 cv is indicated in each case in bold.

2000

1800

1600

1400

1200

1000

800

600

Estuary
WTP
River

400

200

0

0 200 400 600 800 1000 1200 1400 1600 1800 2000

DOC Measured

Figure 10.10. PLS prediction of DOC from fluorescence in the Horsens catchment. A single two-
latent-variable model incorporating data from all sites produces poor predictions for the estuarine
samples.