Effect of Altitudinal and Seasonal Factors on Diatomological Mapping of Waterbodies: Implication in Drowning Investigations

Diatoms are an essential part of forensic investigation in drowning cases. They are used to differentiate between ante-mortem and post-mortem drowning and to ascertain the site of drowning. However, to do so it is imperative to perform the diatomological mapping of water sources in different regions. The issue of localizing a drowning site may be resolved with the help of diatomological monitoring and mapping of the water sources, which generates substantial references for meeting the ‘criterion of concordance’. The present study has generated a database of diatom diversity in relation to different seasons and altitudes. Water sampling was made from low, mid and high altitudes during summer and autumn seasons. Important information was found after a microscopic examination of diatoms in water samples from different water bodies at different geographical altitudes. Twenty-seven diatom genera have been observed in the water samples from the selected localities. The findings of the current study have exposed the significant effect of seasonal changes and varied altitudes on occurrence of diatoms. A variety of commonly occurring site restricted diatoms were identified in the water samples. This useful information can be significant while investigating drowning cases from this particular region when the drowning site is either questioned or unknown.