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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

100%

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

2009

tom Vol. 38, No.3

113-124

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.

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

88%

Gwiazda R.

2009

tom Vol. 38, No.3

135-139

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.

Dynamika zmian warunków świetlnych w stawie karpiowym w okresie hodowlanym

63%

Tokarczyk-Dorociak K. , Drabiński A.

tom Vol. 16, No. 1

93--102

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.

A study of the Baltic water optical transparency

63%

Dera J. , Sagan S.

tom 28

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

63%

Gwiazda R.

tom 38

nr 3

135-139

The impact of environmental factors on zooplankton communities in the Vistula Lagoon

51%

Paturej E. , Kruk M.

nr 2

Composition and distribution of epiphytic midges (Diptera: Chironomidae) in relation to emergent macrophytes cover in shallow lakes

51%

Tarkowska-Kukuryk M.

nr 1

The influence of emergent macrophytes (dominated by Phragmites australis (Cav.) Trin. ex Steud.) on the species composition, richness and abundance of epiphytic midges (Diptera: Chironomidae) was studied in five shallow lakes of eastern Poland during three seasons (May, July and October) of 2001. The lakes represented three states: clear (macrophyte dominated), intermediate (phytoplankton-macrophyte dominated) and turbid (phytoplankton dominated). The trophic status of lake strongly affected the assemblages of chironomids living on the surfaces of common reed. Habitat conditions regulated mostly densities and relative abundance of midge taxa and did not have any significant influence on the number of taxa. The Canonical Correspondence Analysis of epiphytic fauna showed the significance of 5 environmental variables: Secchi disc visibility, dissolved oxygen, reed density, concentration of total phosphorous and epiphytic chlorophyll-a. The analysis separated epiphytic midges into two groups. The first group included taxa limited by low oxygen content and water transparency and corresponds with clear state habitats. To the second group belong taxa typical of eutrophic waters with densities determined by the concentrations of total phosphorous and chlorophyll-a, common in lakes of intermediate state and in particular of turbid state.

Eutrophication rate of lakes in the Jorka River system [Masurian Lakeland, Poland]: long-term changes and trophic correlations

51%

Hillbricht-Ilkowska A.

nr 4