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Changes in the Trophic Status of Lake Niepruszewskie (Poland)

Zbierska J., Ławniczak A. E., Zbierska A.

Journal of Ecological Engineering

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2015

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Vol. 16, nr 4

65--73

EN

The paper presents the evaluation of trophic status of Lake Niepruszewskie in the years 1994–2013. This is the first lake in the Samica Stęszewska river, flowing dis-tally through the lakes of the Wielkopolski National Park. Source part of the Samica Stęszewska river basin was, in the years 2004–2012, included to the nitrate vulnerable zone (NVZ), and Niepruszewskie Lake was considered to be threatened by eutrophication. The evaluation of trophic status of the lake was made based on the concentration of nutrients (nitrogen and phosphorus) and indicators of eutrophication (chlorophyll a, water transparency Secchi disk marked) by referring them to the limit values for the eutrophication of surface waters as defined in the Regulation of the Minister of Environment of 23 December 2002 and other criteria used for the classification of the eutrophication of surface waters. Detailed and synthetic indexes of the trophic status (TSI) using the formula Carlson and the ratio of N:P were also made. Concentrations of the nutrients in Lake Niepruszewskie and eutrophication indexes reached high values, indicating a eutrophic or hypertrophic state of the lake. Detailed values of the trophic status index (TSI), on average over the period, corresponded to eutrophic, while in subsequent years they were varied – from mesotrophic to hypertrophic. The worst trophic status was recorded in 2003–2006, after the lowering of the lake dam-ming. The high value of N: P ratio indicates that the lake has huge surplus of nitrogen, and phosphorus is a productivity limiting factor.

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Development of tools for ecological quality assessment in polish marine areas according to the Water Framework Directive. Part III - Secchi depth

Łysiak-Pastuszak E., Krzymiński W., Lewandowski Ł.

Oceanological and Hydrobiological Studies

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2009

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Vol. 38, No.3

113-124

EN

The implementation of the EU Water Framework Directive (WFD) requires ecological status quantification on the basis of biological and physico-chemical parameters, and an assessment of reference conditions and relevant environmental pressures for the construction of response curves. In this study the linking of water transparency, a proposed eutrophication indicator, to environmental pressure parameters was examined in the Polish sector of the Baltic Sea. Statistically significant linear correlations were detected between nutrient concentrations in sea water and Secchi depth, and between nutrient riverine loads and Secchi depth. The magnitude of acceptable deviation from reference conditions is also discussed.

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Can poor foraging habitat (an inundated opencast sulphur mine) be attractive to the great crested grebe (Podiceps cristatus)?

Gwiazda R.

Oceanological and Hydrobiological Studies

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2009

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Vol. 38, No.3

135-139

EN

During investigations of an inundated opencast sulphur mine (an open, deep water habitat with a relatively small littoral area) only five species of breeding water birds were recorded. The density of breeding great crested grebes Podiceps cristatus was relatively high (c. 1.0-1.1 pairs 10 ha-1 of water, and 1.6-1.8 pairs ha-1 of the macrophyte area) although fish density was very low. High water transparency probably compensated for low prey density, because potential prey could be readily detected. Most of the fish were small and occurred in the upper layers of the water column (they could not live below 10 m where the water was anoxic), so were readily available and easily caught by the grebes.

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Dynamika zmian warunków świetlnych w stawie karpiowym w okresie hodowlanym

Tokarczyk-Dorociak K., Drabiński A.

Przegląd Naukowy Inżynieria i Kształtowanie Środowiska

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2007

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Vol. 16, No. 1

93--102

EN

In the paper there have been presented the results of a field studies performed in 2001-2003 (carp breeding period), in order to establish the dynamism of the light conditions changes in a fish pond. The influence of shade caused by vegetation growing on the shore of the light conditions in the pond has been also analyzed. The results show a great changeability of the light conditions in a breeding period characterized by the tendency to worsen of the light conditions in the pond till the extreme conditions of a complete absorption of the sunlight by the surface layers of the pond water and, observed from the middle of June, 24 hours - night on the pond bottom.