(2020) ZCR Calculations 5 ZCR = [S (Metabolism f(size, T°C) + Production f(size, T°C))]/AE i = 1 where i = size fractions, AE = absorption efficiency (0.70) Mean Day/Night size-fract biomass from upper 150-200 m, mean T°C of EZ Migrant (Night–Day) size-fract biomass, ½ day at mean T°C of 300-500 m This produces MesoZoo with mean GGE = 23.6% MesoZoo GGE Synthesis = 26% (Straile 1997) Special Circum. [...] protistan GGE (Straile1997) ZCR estimates for different systems BATS and HOT data divided into quartiles of lower to higher PrimProd, averaged The quartiles capture the ~2X seasonal and ~2X secular MesoZoo biomass increases observed in each system SEM uncertainties are plotted but smaller than the symbols ZCR estimates for different systems Three subtropical experimental sites are added to the BAT. [...] (2011) Net µ AMBIENT MicroZoo contribution to ZCR Most experiments show that MicroZoo consume a high percentage of daily Prim Prod Exceptions: Coastal upwelling sites, Salp bloom MicroZoo overwhelmed, controlled by predators Full data average = 70.0 ± 3.6% Calbet & Landry (2004) = 67% MicroZoo contribution to ZCR 70% transfer loss Full data average = 70.0 ± 3.6% Full data average = 58.7 ± 4.0% Cal. [...] In general: Bact Prod ≈ 10% Prim Prod Half lost to viruses One trophic transfer = 1.5% Prim Prod Two trophic transfers = 0.45% Prim Prod Williams (1981) Other contributions to ZCR: Carnivory 6 Gulf of Mexico 5 4 % Carnivore DW <1 mm = 13 ± 1% A >1 mm = 69 ± 4% 3 0.2-0.5 0.5-1 1-2 2-5 5+ mm MesoZoo Size Fraction (mm) In a balanced system, carnivory cannot exceed MesoZoo production = 23.6% of ZCR, a. [...] d15 15Nδ (pNpt) Conventional interpretation explains trophic support of MesoZoo Poor systems Bloom systems greater MicroZoo greater MesoZoo contribution contribution Five meet or MicroZoo exceed MesoZoo 100% ZCR with only Micro and MesoZoo Others meet ZCR with carnivory Summary Points Liberal assumptions Healthy, actively growing zooplankton Metabolism = 1.5 X Ikeda (1985), with organic excret.
Authors
- Pages
- 22
- Published in
- Canada
Table of Contents
- M.R. Landry M. Décima M.R. Stukel 1
- Conventional understanding one heterotrophic step of microzooplankton 2
- Can conventional understanding of food web structure explain MesoZoo biomass variability 3
- Data Sources 4
- MesoZoo biomass relationship to system PrimProd 5
- Zoopl Carbon Requirements ZCR for metabolism and growth 6
- Assumptions 6
- ZCR Calculations 7
- ZCR Metabolism size TC Production size TCAE 7
- Special Circumstance 7
- Salp Bloom Experiments SP 7
- ZCR 3X Metabolism size TC0.70 7
- ZCR estimates for different systems 8
- ZCR estimates for different systems 9
- ZCR estimates for different systems 10
- ZCR estimates for different systems 11
- ZCR estimates for different systems 12
- Can grazing rate estimates satisfy ZCR 13
- Same net tows and size fractions as biomass. Measured as Phaeo x Gut Turnover Rate TC to get Chl consumed d converted to C measured Phyto CChl . 13
- Graz gut Chl size-binned individuals 13
- Arabian Sea MesoZoo grazing by C method incubation 13
- Six of 8 process studies resolved 1 steady-state balances of phyto growth and grazing or 2 showed experimental rates consistent with 14
- MicroZoo contribution to ZCR 15
- MicroZoo contribution to ZCR 16
- MesoZoo contribution to ZCR 17
- MesoZoo contribution to ZCR 18
- Other contributions to ZCR Bacteria via Microbial Loop 19
- Other contributions to ZCR Carnivory 20
- Conventional interpretation explains trophic support of MesoZoo 21
- Five meet or exceed 100 ZCR with only Micro and MesoZoo 21
- Others meet ZCR with carnivory 21
- Summary Points 22
