Abstract
Systematic collections of peat mid-infrared spectra and other peat properties are scarce, but useful to understand peat chemistry and develop spectral prediction models. The Peatland Mid-Infrared Database ('pmird') stores 3877 mid-infrared spectra of peat, peat-forming vegetation, and dissolved organic matter, together with measurements of other peat properties that were collated from previous studies. Most of the peat samples are from northern bogs, whereas southern or tropical peat and fen peat is underrepresented. The data are supplemented with metadata on sample origin, sample processing, measurements, and quality indicators on whether spectra are baseline corrected or not and on the relative contribution of water vapor, carbon dioxide, and noise to the spectra. The 'pmird' database can be used to analyze peat properties, develop and test spectral prediction models, and develop data and metadata standards.