B. Papp szerk.: Studia Botanica Hungarica 32. 2001 (Budapest, 2001)

Buczkó, Krisztina; Rajczy, Miklós: Changes of attached diatoms in a dead arm of the Danube between 1992-1999 at Ásványráró (Szigetköz section)

30% 24% 18% 12% 6% 0% LZL JUL Fig. 6. Changes of relative abundance of Cocconeis placentula between 1992 and 1999. The samples collected in 1999 are black. The changes between 1999 and the earlier years can easily be followed by the relative abundance of the dominant taxa. The dominant species of the nineties was Achnanthes minutissima. Its relative abundance decreased in 1999 (Fig. 5). The 20% T 16% 12% 8% 4% 0% Fig. 7. Changes of relative abundance of Amphora pediculus between 1992 and 1999. The samples collected in 1999 are black.