Epiphytic algae of aquatic macrophytes from some oxbow lakes of Central Kalimantan

Epiphytic algae of aquatic macrophytes were studied in Lake Tabiri, Lake Takapan and Lake Rengas in 2002. The study was conducted to reveal the composition and abundance of epiphytic algae in immersed parts of some aquatic macrophytes in humic lakes. Epiphytic algae were studied from Salvinia molesta, Eichhornia crassipes, Cyrtococcum sp as representatives of floating aquatic macrophytes and Polygonum lapathifolium as a submerged macrophytes that grow from the bottom reaching to the surface of the lake. Diatoms or Bacilllariopyceae group dominated the epiphytic algae community. Beside diatom, a group of desmids are commonly found in' this community of epiphytic algae. The abundance of epiphytic algae collected on E crassipes range from 1,790,036 to 286,898,867 cell/m, while the abundance of epiphytic algae collected on Cyrtococcum sp range from 2,793,424 to 123,984,278 cell/m 2. The abundance of epiphytic algae colleted on S. molesta and P. lapathifolium were 1,731,767 and 119,022,754 cell/m respectively. The abundance of epiphytic algae is higher in Lake Tabiri compared to the abundance of epiphytic algae collected from the same species of aquatic macrophytes found in Lake Takapan and Lake Rengas. The highest abundance of epiphytic algae in Lake Tabiri may be influenced by some environmental factors such as pH, conductivity and Secchi depth that were found in higher in that lake. The architecture of aquatic macrophytes seems influence the abundance of epiphytic algae in Lake Tabiri.