Abstract:
The research was conducted from March to June 2012 in water of Mesjid
River Estuary of Dumai City Riau Province. The goal of this research is to
describe the variations of niunber and composition species of planktonic diatom
among the Mesjid River Estuary Water and environmental factors that affect it.
Survey method was applied to collect data by observation, measurement and
sampling in the field, followed by the identification of diatom samples at
Integrated Laboratory of Marine Sciences, Faculty of Fisheries and Marine
Science, University of Riau. Total number of epiphytic diatom spesies were 12
species with small variation from river body to mouth estuary. Beside that, there
are six species namely Chaetoceros debilis, Planktoniella sp., Pleurosigma
normanii, Nitzschia seriata, Coscinodiscus sp., dan Hyalodiscus 5/7.found at all
stations. The lowest density of planktonic diatom is found at station 4 (16529
cell/1) and The highest is at station 3 (35420 cell/1).
The measurement of water quality parameters shows that the condition of
the waters in the Sungai Mesjid of as whole is still in balance, there is no
competition for place nor food and water quality middle level of contamination.
