Are fishponds really a trap for nutrients? – a critical comment on some papers presenting such a view / Czy stawy rybne są rzeczywiście pułapką dla pierwiastków biogennych? – krytyczny komentarz do pewnych prac prezentujących taki pogląd

Abstract

Abstract There is still a controversy about the environmental impact of fishponds, especially on their ability to retain nutrients. This paper presents some basic rules of nutrient cycling in running and stagnant waters and the biotic and abiotic transformation of nutrients delivered to dam reservoirs and fishponds. Based on these common properties of eutrophic stagnant waters, some critical remarks are presented on papers that claim to prove the capacity of fishponds to retain nutrients (mainly nitrogen) during fish production and after pond drainage. Finally, some ways of reducing negative environmental impacts of fishpond effluents are described as an indirect evidence that such impacts really pose a threat to water quality