Different analysis techniques for fluorescence excitation–emission matrix spectroscopy to assess compost maturity

Assessment of compost maturity is essential for achieving high quality compost. In this study, fluorescence excitation–emission matrix spectroscopy combined with different analysis techniques was applied to improve the sensitivity of compost maturity assessment. Results showed that composts in two parallel piles could be believed mature after 37 d when combined with the evolution of temperature, chemical and biological indices in the two piles. Pearson correlation between the common maturity indices and fluorescence analysis parameters demonstrated that fluorescence regional integration (FRI) had a higher correlation coefficient than that of fluorescence intensities and the ratios of peaks, suggesting that FRI technique is more suitable to characterize the maturity of compost than the other two analysis techniques, i.e., peak intensity and peak ratio. Furthermore, the fluorescence spectroscopy combined with FRI analysis could be used as a valuable industrial and research tool for assessing compost maturity.