caa a22 4500 465762174 CHVBK 20180323111902.0 cr unu---uuuuu 170327e19900601xx s 000 0 eng 10.1007/BF00902376 doi (NATIONALLICENCE)springer-10.1007/BF00902376 Pelagic food web interactions and hypolimnetic oxygen depletion: Results from experimental enclosures and lakes [Elektronische Daten] [Asit Mazumder, D. McQueen, W. Taylor, D. Lean] Large lakes enclosures were used to examine the influence of nutrient (P, N) enrichment and planktivorous fish (1 + yellow perch) predation on hypolimnetic oxygen depletion. Results were compared to similar data for lakes with high (Lake St. George) and low (Haynes Lake) abundances of planktivorous fish. In both the unfertilized and fertilized enclosures, fish predation on large cladocerans increased the biomasses of pico- and nanoplankton (0.2-20 µm), phytoplankton (chlorophyll a) and total phosphorus (TP), reduced sedimentation, water clarity, and hypolimnetic oxygen concentrations (AHO). Fertilized enclosures without fish had highest TP and sedimentation rates, but the AHO were low. The high planktivore lake had higher pico- and nanoplankton, higher chlorophyll a, reduced water clarity, and lower AHO than the low planktivore lake. Areal hypolimnetic oxygen depletion (AHOD) rates were strongly related with Secchi depth and plankton size-distribution (r 2 = 0.77, and 0.79, respectively), but not as strongly with TP, chlorophyll a, and sedimentation rates (r 2 = 0.25, 0.53, and 0.02, respectively). Such observations are useful in forming a generalized hypothesis that lakes with low planktivory and high water clarity have lower oxygen depletion because 1) plankton that are settling are larger and spend less time in the hypolimnetic water column before reaching the sediment, and therefore undergo less decomposition, and 2) the euphotic depth extends into the hypolimnion and production of oxygen can take place. Birkhäuser Verlag, 1990 Pelagic food webs nationallicence hypolimnetic oxygen depletion nationallicence lake restoration nationallicence water clarity nationallicence predation and fertilization nationallicence enclosure experiment nationallicence Mazumder Asit National Water Research Institute, P.O. Box 5050, L7R 4A6, Burlington, Ontario, Canada aut McQueen D. Department of Biology, York University, M3J 1P3, North York, Ontario, Canada aut Taylor W. Department of Biology, University of Waterloo, N2L 3G1, Waterloo, Ontario, Canada aut Lean D. National Water Research Institute, P.O. Box 5050, L7R 4A6, Burlington, Ontario, Canada aut Aquatic Sciences Birkhäuser-Verlag 52/2(1990-06-01), 144-155 1015-1621 52:2<144 1990 52 27 https://doi.org/10.1007/BF00902376 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/BF00902376 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Mazumder Asit National Water Research Institute, P.O. Box 5050, L7R 4A6, Burlington, Ontario, Canada aut NATIONALLICENCE 700 1- McQueen D. Department of Biology, York University, M3J 1P3, North York, Ontario, Canada aut NATIONALLICENCE 700 1- Taylor W. Department of Biology, University of Waterloo, N2L 3G1, Waterloo, Ontario, Canada aut NATIONALLICENCE 700 1- Lean D. National Water Research Institute, P.O. Box 5050, L7R 4A6, Burlington, Ontario, Canada aut NATIONALLICENCE 773 0- Aquatic Sciences Birkhäuser-Verlag 52/2(1990-06-01), 144-155 1015-1621 52:2<144 1990 52 27 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer