Buried Cadaver Decomposition Process in Soil 1331 Decomposition Process

Death is characterised by the end of vital activities (so-called negative markers) and positive markers responsible for modifications for morphology and structure of the body (Campobasso et al. 2001). Negative markers, appearing immediately after the stop of activity of the heart, loss of breathing and circulation, are followed by fall of body temperature (calor mortis), rigidification (rigor mortis), apparition of lividity (rubor mortis), dehydration and acidification. Positive markers are rather destructive, with degradation of tissues (organic matter) caused by autolysis, autodigestion and putrefaction, involving action of anaerobic and aerobic bacteria or fungi. Results of this last process can be very different according to the environment. In a dry medium, the decay is rather dry and is called mummification. In wet conditions, or in an aqueous environment, it is called adipocere because of the appearance of waxy substances.

Regarding exposed corpses, most of the authors consider five stages of decomposition: fresh, bloated, putrefied, active putrefied, and dried remains. However, some of them proposed four to six stages of decomposition (Payne 1965). In burial environment, such modifications are hard to observe, unless little holes are dug into exhuming carcasses during the experiment. Continuous control of this process is not easy and observations are less accurate than in open air.

Payne et al. 1968 buried baby pigs at 50-100 cm deep in a clay soil from June to November (5 months). They observed five stages of decomposition: fresh, inflation (5 days after burial), deflation decomposition (+10), disintegration (+25), and skeletonisation (+80). Vanlaerhoven and Anderson (1999) used lambs (33 kg at 30 cm deep, 16-month experiment from June) and proposed five stages too: fresh (until 2 weeks after burial), bloated (6 weeks), active decay (3 months), advanced decay (11 months), and dry remaining stages (16 months). Turner and Wilshire (1999) buried pigs (55 kg) at 10 cm deep from December to April (5 months, cold conditions). They observed an active decay on carcasses 5 months after burial, but no skeletonisation.

Thus, the number and the duration of the decaying stages are not always similar but depend on several parameters, either biotic or abiotic.

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