Distribution and concentration several types of heavy metal correlated with diversity and abundance of microalgae at Tallo Estuary, Makassar, South Sulawesi, Indonesia

The main problem of aquatic ecosystem is caused by pollution of heavy metal that comes from industrial disposal and domestic. This pollution is causing loss of biodiversity, also increasing of bioaccumulation and biomagnifications from the poisonous materials at the food web. River ecosystem is the most affected by aquatic pollution due to a major role of the river for community. A study on water quality, heavy metal concentration and microalgae abundance at selected sites of Tallo River was carried out. Eighteen water and sediment samples were collected along the river for heavy metal and water quality analysis and 27 water samples were collected for microalgae analysis. The aims of this research are: 1) Determine distribution and concentration of existing heavy metal Tallo River ecosystem, 2) Identify microalgae dominant from Tallo River ecosystem where have been polluted by several type of heavy metal. The results showed that there were three heavy metals at Tallo River which have a high concentration and above permissible maximum concentration of environment quality standard, such as Lead (Pb), Copper (Cu) and Chromium (Cr). Those heavy metals were distributed patchily between station sampling. The highest concentrations of those heavy metals were found close to the industrial location of the Tallo River. Statistical result showed that there was a significant different of heavy metal concentration between sampling stations and concentration all of heavy metal measured was higher at sediment than in the water column. Only four genera found during sampling. Skeletonema sp and Synedra sp were abundance at all sites of the research location. However, there is a weak regression between abundance of microalgae, species dominant and concentration of heavy metal (Pb, Cu and Cd) in the sediment and water column.