Naslov
Macrozooplankton and macrozoobenthos communities of four shallow urban lakes

Autori
Ternjej, Ivančica ; Popijač, Aleksandar ; Mihaljević, Zlatko ; Previšić, Ana ; Žganec, Krešimir ; Kerovec, Mladen

Vrsta, podvrsta i kategorija rada
Sažeci sa skupova, sažetak, znanstveni

Izvornik
Book of Abstracts of the 5th international Symposium on the ecology and management of Shallow Lakes "Shallow Lakes in a changing world"(Shallow Lakes 2005) / Boers, Paul - Dalfesn, 2005, 102-103

Skup
International Symposium on the ecology and management of Shallow Lakes "Shallow Lakes in a changing world" (5 ; 2005)

Mjesto i datum
Dalfsen, Nizozemska, 05.06.2005. - 09.06.2005

Vrsta sudjelovanja
Poster

Vrsta recenzije
Međunarodna recenzija

Ključne riječi
macrozooplankton; macrozoobenthos; shallow urban lakes

Sažetak
The macrozoobenthos and macrozooplankton communities of four shallow urban lakes in the centre of Zagreb were investigated from March to December 2003. The lakes are influenced by human activity because they are a part of a big recreational park Maksimir. All lakes share the same drainage area, but three of them are directly connected through the feeding stream Bliznec. Macrozooplankton was collected in each lake, at the deepest point with pulling the plankton net (80 µ ; ; m) in vertical haul from the bottom to the surface. Abundance and biomass were calculated from these quantitative samples. Quantitative samples of macrozoobenthos were collected at two stations in each lake using an Ekman grab (sampling area 0.01 m2). Physico-chemical parameters (dissolved oxygen, oxygen saturation, biological oxygen demand, temperature, pH, total dissolved solids, conductivity, nitrate, nitrite, ammonium, orthophosphate, chlorophyll a and transparency) were also measured. Bliznec stream flows through populated village and city area collecting untreated wastewater from the households. That makes Bliznec the main source of organic and inorganic pollution, which influence benthos and plankton community especially in two shallower lakes (max. depth app. 2 m). Species Bosmina longirostris and some small detritivorous cladocerans dominate macrozooplankton. They are most abundant during summer. Macrozoobenthos is at the same time characterized by large numbers of Tubificidae (70-90% of macroinvertebrate community) especially species Limnodrilus hoffmeisteri, Potamothrix bavaricus, and P. hammoniensis. The other two lakes are deeper (max. depth app. 5-7 m). Copepod Eudiaptomus gracilis and cladoceran Daphnia longispina dominate the plankton community. Portion of Tubificidae family in benthos community is reduced (35-50%). Diversity of Naididae family increased from one to six species, and dipteran families Chironomidae and Chaoboridae make a large part of macroinvertebrate community (28-40%). Chemical parameters especially nitrate and phosphate had high values in two shallower lakes confirming their higher trophic state. These lakes are surrounding the city ZOO, and large flocks of waterfowls are living there and feeding on food thrown from visitors. The other two, deeper lakes, are slightly isolated deeper in the park and surrounded by forest, as an additional source of organic matter.

Izvorni jezik
Engleski

Znanstvena područja
Biologija

POVEZANOST RADA