[Change rules of quantity and species of diatoms in Hunhe River in Shenyang]

To observe the change rules of quantity and species of diatoms in Hunhe River in Shenyang and to provide technology and scientific evidence for drowning identification and the location of drowning in forensic investigation.

In 2011, different locations for collecting water samples were chosen in Hunhe River in Shenyang. Water samples were collected and variation of quantity and species of diatoms were observed every month. And variation of dominant species of diatoms was observed every week.

The quantity, species and dominant species of diatoms in Hunhe River in Shenyang varied with different time and locations. The quantity and species of diatoms were lowest from December to February and gradually increased, reaching peak in May and second peak in October, and then gradually decreased. The dominant species of diatoms varied significantly adjacent two weeks at same location from April to November, but had little changes at different locations in same week from July to August.

The change rules of quantity and species of diatoms are complicated and affected by various factors such as environment and hydrology. The change rules of species and quantity of diatoms should be considered in forensic investigation of drowning identification and the location of drowning.