Stable isotope analysis of food webs in wetland areas of Lake Balaton, Hungary abb;5
Tátrai, István; Mátyás, Kálmán; Korponai, János; Paulovits, Gábor; Pomogyi, Piroska; Présing, Mátyás
published: Sep 16, 1999
ArtNo. ESP141014601006, Price: 29.00 €
Stable carbon (δ13C) and nitrogen (δ15N) isotopes were used to analyze the source and transformation of organic matter in the food web of the Kis-Balaton Water Protection System (KBWPS). The extent of the isotopic shift between trophic levels deviated significantly from typical values of 1 ‰ for carbon and 3.5 ‰ for nitrogen. The δ13C enrichment factor in food chain benthos > cyprinid prey fish > predatory fish (pike-perch, pike) was over 2 ‰ in the KBWPS. Variability in δ13C in the KBWPS reservoir would be dampened because of the high ratio of dissolved inorganic carbon and also it may reflect inputs of terrestrial organic carbon through the main inflow. The trophic fractionation of 15N appears to be more pronounced in fish than in invertebrates. The isotopic shift in the food web of the reservoir proved to be lower than 3.5 ‰ and was 2.9 ‰. Our isotope evidence indicated that there might be strong competition for food resources between bream and prussian carp on the one hand and between common carp and roach on the other. Pike-perch and pike depended on omnivores such as bream and prussian carp as food.