Diatomological Mapping of Water Bodies in Chongqing Section of the Yangtze River and Jialing River

The diagnosis of drowning is one of the most difficult in forensic medicine. Forensic diatomology has been proposed to be useful in solving the diagnosis of drowning and considered to be a reliable indicator of the site of drowning. The Yangtze River and Jialing River are the main rivers in the Chongqing area (China), and a large number of corpses are found in the rivers every year. However, the distribution of diatoms in the rivers was not fully studied. In the presented study, a Microwave Digestion-Vacuum Filtration-Scanning Electron Microscopy (MD-VF-SEM) method was performed to acquire the qualitative and quantitative data of diatoms of water samples collected from 10 different sites of the Yangtze River and Jialing River in Chongqing section during different seasons. Our study not only created the diatomological maps of water bodies in Chongqing section of the Yangtze River and Jialing River for the first time but also identified some seasonal and site-specific diatoms that can be taken as markers of particular sites or seasons of drowning. The results of our study may provide forensic scientists helpful reference in solving the drowning cases.