The effects of anthropogenic pollution on the Kanev Reservoir (Ukraine) phytoplankton. Comparison of size spectrum patterns

摘要

The aim of this investigation was to compare the structure of the phytoplankton assemblage in two parts of Kanev Reservoir characterized by different levels of urban pollution. The analysis of pattern variability for several types of size spectra, namely the biomass size spectrum (BSS), the normalized size spectrum (NSS) and the traditional taxonomic size spectrum (TTSS), was made on the basis of a routine monitoring dataset collected during a 24-month period at two stations on the Kanev Reservoir (Ukraine). While station I was situated in a relatively pure area of river part of the reservoir, station 2 was located lower down it, at the mouth of the Syrets River, which bears the outflow of Kiev sewage. The investigated stations were characterized by markedly different phytoplankton composition and dynamics. While the BSS curves were very different, the annual NSS and TTSS curves had a similar general pattern, with some differences evidenced in the fine structure of each spectrum. The obtained indices of traditional taxonomic dimensional spectrum, which characterize the state of phytoplankton in a relatively pure area of the Kanev Reservoir and contaminated by urban drains of Kiev sewage at the mouth of the Syrets River, are compared with the same of fresh-water clean reservoir, in particular Lake Kinneret (Israel). The impact of the urban pollution, as evidenced through the deformations of the size spectrum patterns, is discussed in detail.