Spectral images on shallow graves and reference plots

When a person goes missing and a crime is suspected, police forces may scout for clandestine graves in certain areas in which the victim is suspected to have been buried. Such clandestine graves are often shallow and may affect the vegetation on top and around the grave for prolonged periods of time. Search efforts by visual means are only effective in detecting the effects of graves on vegetation when the effects are very pronounced. However, it is hypothesized that even when a visual observer cannot discern the effect from natually occurring variance, the spectral characteristics of the vegetation may still be sufficiently different to be able to be picked up through chemometric methods. This study aimed to explore if and how spectral imaging could be used to discriminate between the vegetation growing on shallow graves and on nearby reference plots. Data were acquired in the visible/near-infrared (Vis-NIR, 400–900 nm) and short-wave infrared (SWIR, 1000–1700 nm) with mobile spectral imaging set-ups and used to train and validate spectral classification models.