Chelatable iron in the sub-tropical Lake Kinneret : Its seasonal variation and impact on carbon uptake by natural algal assemblages and monoalgal cultures

• Published in: Aquatic sciences Vol. 60; no. 2; pp. 157 - 168
• Main Authors: PARPAROVA, R, YACOBI, Y. Z
• Format: Journal Article
• Language: English
• Published: Heidelberg Springer 1998
• Subjects: Animal, plant and microbial ecology; Aphanizomenon ovalisporum; Applied ecology; Biological and medical sciences; Ecotoxicology, biological effects of pollution; Fresh water environment; Freshwater; Fundamental and applied biological sciences. Psychology; Peridinium gatunense; Asia; Israel; Israel, Kinneret L; Freshwater environment; Seasonal variation; Algae; Lakes; Phytoplankton; Iron; Bioavailability; Concentration; Photosynthesis; Thallophyta
• ISSN: 1015-1621; 1420-9055
• DOI: 10.1007/s000270050032

The concentrations of chelatable iron in Lake Kinneret, defined as the fraction bound by 8-oxyquinoline (oxine) ranged in the euphotic zone between 0.24 and 2.36 mu g l super(-1). This iron species represented an average of 8.1 and 5.0% of dissolved ionic (Fe sub(i)) and total iron (Fe sub(t)), respectively. Removal of the chelatable iron by oxine additions to lake water samples reduced super(14)C uptake by up to 87% of the control value. The impact of oxine addition was low when the lake phytoplankton was dominated by the dinoflagellate Peridinium gatunense and particularly high when the cyanophyte Aphanizomenon ovalisporum was the most abundant phytoplankton. The impact of oxine was most prominent near the water surface and declined with depth. Experiments showed that cultures of Peridinium and diatoms were significantly less sensitive to oxine iron binding than chlorophytes and cyanophytes, thus matching the findings with natural assemblages.