Diatoms of the lower Vistula River phytoseston [RESEARCH ARTICLE]

Abstract

This paper presents the results of research on the phytoseston of the Vistula River along a distance of 163 km. The research was conducted between 1994 and 2010. A total of 218 diatom taxa were identified in the phytoseston. A large number of diatoms were represented by only a few specimens, and, in some cases, only in one of the 312 samples examined. Only nine species had the highest constancy of occurrence in the lower Vistula River; however, mostly periphyton and benthos species predominated the phytoseston in the Vistula River at all of the stations. Most of the species were cosmopolitan. The eutrophic conditions of the Vistula River were confirmed by the great number of eutraphentic diatom taxa. The 86 diatom species identified that have high or very high oxygen requirements confirm that oxygen conditions in the river are good. The ecological potential of the Vistula River was rated based on concentrations of chlorophyll a. The worst state, which was moderate, was recorded in 1998 at positions above the dam in Włocławek. Research on the river segment in Toruń in the 2007-2010 period indicated the ecological potential had improved from good to maximum. Despite high anthropogenic pressure and major engineering projects, the Vistula River is characterized by good and maximum ecological potential and great biodiversity.

CORRESPONDING AUTHOR:

E. Dembowska [+]
Department of Hydrobiology
Faculty of Biology and Environmental Protection
Nicolaus Copernicus University
Lwowska 1, 87-100 Toruń, Poland
Tel./Fax: +48566114450, +48566114443;
e-mail: dembow@umk.pl