The biological fluorescence index (BIX) is calculated by dividing the fluorescence at excitation 310 nm and emission at 380 nm (ex = 310, em = 380) by that at excitation 310 nm and emission at 430 nm (ex = 310, em = 430).
eem_biological_index(eem, verbose = TRUE)
| eem | An object of class |
|---|---|
| verbose | Logical determining if additional messages should be printed. |
An object of class eemlist.
A data frame containing the biological index (BIX) for each eem.
Different excitation and emission wavelengths are often used to measure
EEMs. Hence, it is possible to have mismatchs between measured wavelengths
and wavelengths used to calculate specific metrics. In these circumstances,
EEMs are interpolated using the interp2 function from the
parcma library. A message warning the user will be prompted if data
interpolation is performed.
Huguet, A., Vacher, L., Relexans, S., Saubusse, S., Froidefond, J. M., & Parlanti, E. (2009). Properties of fluorescent dissolved organic matter in the Gironde Estuary. Organic Geochemistry, 40(6), 706-719.
http://doi.org/10.1016/j.orggeochem.2009.03.002
file <- system.file("extdata/cary/scans_day_1/", package = "eemR") eem <- eem_read(file, import_function = "cary") eem_biological_index(eem)#> sample bix #> 1 nano 2.6812045 #> 2 sample1 0.7062640 #> 3 sample2 0.8535423 #> 4 sample3 0.4867927