Transport of biogenic matter along the course of the Szeszupa River in the Suwalski Landscape Park (SLP) occurs in accordance with the river continuum concept. Only TP concentration decreases along the river’s course. TP and TOC concentrations classify the Szeszupa River to the moderate ecological state. The ecological state of three lakes (Linówek, Pogorzałek, and Perty) in the Szeszupa River catchment was estimated as very good. The remaining lakes, due to high TP concentrations, belong to the moderate state. The management of the catchment affects the amount of biogenic matter supplied to the Szeszupa River. The highest proportion of forests in the Jaczniówka River catchment clearly results in a decrease in the amount of biogenes in the river. The remaining partial catchments, with a higher proportion of arable land, meadows, and pastures, provide higher amounts of bioelements. The loads of bioelements stored in lakes in the summer period are determined by the size of the lakes (surface area of a lake and volume of water accumulated in the lake basin). This directly suggests a lack of anthropogenic activity in the catchments or the very slight effect of it on the lakes’ ecological and trophic state.
Elżbieta Jekatierynczuk-Rudczyk, Piotr Zieliński and Katarzyna Puczko
Stawy Dojlidzkie (The Dojlidy Ponds) are located in the north-eastern part of Poland, near the capital of the Podlasie province, in Białystok. The Dojlidy Ponds (DP) are a complex of more than 20 reservoirs arranged adjacent to one another in an area of about 140 hectares. The largest recreation reservoir (Plażowy) is located within the city limits. Its total area is 34 hectares, it has a capacity of 597 040 m3 and a maximum depth of approximately 2.5 m. DP are supplied by a tributary of the Dojlidy Górne and the River Biała, the principal river of Bialystok. Water tests of a limnic and lenitic character in the upper part of River Biała catchment in Bialystok were conducted from March to October 2014. Referring the obtained results to the actual norms, it can be concluded that most of the parameters analyzed in DP can be assigned to the first class of surface waters. Exceptions were the iron ions, orthophosphates (SRP), total phosphorus (TP), Kjeldahl nitrogen, and also water color and DOC. According to the evaluation of trophic status, the water of DP is eutrophic. The average value of TSI was 55 in the water of the tested objects. The obtained results show that the ecological status of water in the largest pond within the DP complex, in accordance with, the Ecological State Macrophyte Index (ESMI) represent to the good state.
Jolanta Ejsmont-Karabin, Andrzej Górniak, Elżbieta Jekatierynczuk-Rudczyk, Maciej Karpowicz and Adam Więcko
Rotifer abundance and species composition in lakes of the Suwalki Landscape Park were studied in the years 1983–1985, 2009, 2012 and 2015. Rotifer trophic state indices (TSIROT) were used to assess changes in the trophic state of the studied lakes. In most lakes of the Suwalki Landscape Park, there were no changes in rotifer communities over the 25–32 year period to indicate a decline in trophy of the lakes. However, in lakes with the strongest decline in TSIROT values, the values of indicative parameters widely varied in 2015, which may indicate that the status of rotifer communities in the lakes may be dependent on non-trophic factors.