Original paper

Influence of environmental variables on the temporal and spatial distribution of phytoplankton species in a dystrophic and meromictic lake (Lunzer Obersee, Austria)

Ruzicka, Katerina; Fesl, Christian; Schagerl, Michael

Abstract

In the year 2002 phytoplankton samples were collected from lake Lunzer Obersee, a small meromictic and dystrophic mountain lake with a floating mat. Four sites were sampled on 14 dates, abiotic variables as temperature, conductivity, dissolved oxygen, pH, alkalinity, hardness and light intensity as well as the chemical parameters NO2-N, NO3-N, NH4-N, SRP and TP were measured. A cluster analysis based on biovolume data resulted in a seasonal distribution of algal species with the exception of the sampling site ML - the location within the floating mat. In order to determine characteristic species for each group, an Indicator Species Analysis resulting in 23 indicator species was performed. In a Detrended Canonical Correspondence Analysis (DCCA) the indicator species were related to environmental factors. The DCCA pointed out that temperature, total phosphorus, conductivity and pH are the key variables for algal distribution.

Keywords

phytoplankton communitydystrophdccahigh mountain lake