Abstract:
Drowning deaths were caused by the entry of fluid into the respiratory tract through the mouth or nose that will cause asphyxia. Diatoms will associated with the water entering the respiratory tract. Determining the type and abundance of diatoms could be used as a diagnostic support to identify the drowning site. The present research aimed at describing the species and abundance of diatoms in Siak river especially at Sungai Apit area. Samples were taken from three stations, based on secchi disk depth in research area. The stations were divided into three sub-sampling point (left side, center, and right side of the river). Samples were taken by using water sampler of about 60 L and filtered by using planktonnet number 25. Filtered water samples were entered into bottle sample for 100 ml, given lugol as preservative, and taken to the laboratory for analyzing. The examination of diatoms form and type was done by using binocular microscope and Masaharu (1977) and Yunfang (1995) identification book. While diatom density were calculated following method of American Public Health Association (APHA).
It revealed that 14 diatoms species were identified which consisted of Asterionella sp, Amphipora sp, Diatome sp, Planktonema sp, Gyrosigma sp, Melosira sp, Navicula sp, Nitzschia sp, Synedra sp, Eucampia sp, Isthmia sp, Aulacoceita sp, Rhizosolenia sp and Surirella sp. Total abundance of diatom account 28.500 cells/L. Apparently, Nitzschia sp were dominant in the water which abundance of 10.260 cells/L.
