Issn 1730-413x
نویسندگان
چکیده
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 of water, and 1.6-1.8 pairs ha 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. 1 Corresponding author: [email protected] DOI 10.2478/v10009-009-0036-2 Short communication Received: Accepted: January 21, 2009
منابع مشابه
Issn 1730-413x
Nutrients, pH, and organic matter were determined in water samples collected from the Raba River above Dobczyce Reservoir (meso-eutrophic), from the Dunajec River above Czorsztyn Reservoir (mesotrophic), and Rożnów Reservoir (eutrophic), and in the bottom sediments of the reservoirs. The river waters were alkaline (pH 7.2–9.2). In the Raba River and Dunajec River, the ranges of nutrients and or...
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متن کاملIssn 1730-413x
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