Rapid estimation of compost enzymatic activity by spectral analysis method combined with machine learning.

Highlights: [•] We modeled compost enzymatic activity with VisNIR DRS spectra. [•] We examined 7 spectral pretreatments and 6 multivariate models. [•] Spectral separations were found for different compost types. [•] Artificial neural network was best for assessing compost enzymatic activity. [•] VisNIR DRS is promising for rapidly quantifying compost enzymatic activity. [ABSTRACT FROM AUTHOR]