<abstract xmlns="http://www.w3.org/1999/xhtml">

Phytoseston studies were carried out at two sites near the town of Łask in the third orderstream segment of the Grabia River and the first order-stream segment of the Brodnia River, in two study periods: 1992-1993 and 2005-2006. Water and seston were sampled twice a month. The chemical parameters of N-NO3, P-PO4 and chlorophyll <italic>a</italic> were also determined. The aim of the studies was to determine the changes in the nutrient load of these ecosystems in the rivers studied over the course of 12 years and their influence on quantitative and qualitative phytoseston differentiation.No important differences in the taxonomic composition of the phytoseston between the two rivers were observed. A high participation of diatoms (over 50%), in relation to other algal groups, was recorded in both rivers. Vegetation in the Brodnia River begins to develop one month earlier than in the Grabia River. The greatest changes in the seasonal rate of algal succession occurred in the spring and summer periods, while no considerable changes in seston composition were recorded in the fall or winter periods. A decrease in phytoseston quantity was observed in the second study period. Chlorophyll <italic>a</italic> content was significantly lower in 2005-2006 than that in 1992-1993.
</abstract>

Phytoseston studies were carried out at two sites near the town of Łask in the third orderstream segment of the Grabia River and the first order-stream segment of the Brodnia River, in two study periods: 1992-1993 and 2005-2006. Water and seston were sampled twice a month. The chemical parameters of N-NO3, P-PO4 and chlorophyll a were also determined. The aim of the studies was to determine the changes in the nutrient load of these ecosystems in the rivers studied over the course of 12 years and their influence on quantitative and qualitative phytoseston differentiation.No important differences in the taxonomic composition of the phytoseston between the two rivers were observed. A high participation of diatoms (over 50%), in relation to other algal groups, was recorded in both rivers. Vegetation in the Brodnia River begins to develop one month earlier than in the Grabia River. The greatest changes in the seasonal rate of algal succession occurred in the spring and summer periods, while no considerable changes in seston composition were recorded in the fall or winter periods. A decrease in phytoseston quantity was observed in the second study period. Chlorophyll a content was significantly lower in 2005-2006 than that in 1992-1993.

Qualitative and quantitative phytoseston changes in two different stream-order river segments over a period of twelve years (Grabia and Brodnia, central Poland)

Oceanological and Hydrobiological Studies

Phytoseston studies were carried out at two sites near the town of Łask in the third orderstream segment of the Grabia River and the first order-stream segment...

Qualitative and quantitative phytoseston changes in two different stream-order river segments over a period of twelve years (Grabia and Brodnia, central Poland)

Published Online: Apr 02, 2009

Page range: 55 - 63

DOI: https://doi.org/10.2478/v10009-009-0003-y

Keywords
Phytoseston, Grabia and Brodnia streams, changes after 12 years

This content is open access.

Qualitative and quantitative phytoseston changes in two different stream-order river segments over a period of twelve years (Grabia and Brodnia, central Poland)

Published Online: Apr 02, 2009

Page range: 55 - 63

DOI: https://doi.org/10.2478/v10009-009-0003-y

KeywordsPhytoseston, Grabia and Brodnia streams, changes after 12 years

This content is open access.

Keywords
Phytoseston, Grabia and Brodnia streams, changes after 12 years