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Phytoplankton Entrainment and distribution in the Pelagic C. Reynalds, Chapter 2 Ecology of Phytoplankton. Paul Simonin John Bisgrove. Higher density Higher viscosity Higher melting point Higher boiling point Lower compressibility Polar molecule Aquo polymers High specific heat.
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Phytoplankton Entrainment and distribution in the PelagicC. Reynalds, Chapter 2Ecology of Phytoplankton Paul Simonin John Bisgrove
Higher density Higher viscosity Higher melting point Higher boiling point Lower compressibility Polar molecule Aquo polymers High specific heat Density is greatest at 3.98 Celsius Rate of density change increases as heated above Physical Properties of Water
Viscosity and Turbulence • Turbulent Intensity • Product of root mean squares of time averaged fluctuations (u*)2 • Turbulent velocity (u*)
Turbulent Dissipation • Environmental grain • The size and velocities decrease with transfer Wind Velocities must equal or create heat Total volumes must equal
Regulation of Density • Densities of cellular components • Proteins ~1,300 kg m-3 • Carbohydrates ~1,500 kg m-3 (cellulose) • Nucleic acids ~1,700 kg m-3 • SiO2 ~2,600 kg m-3(diatom walls) • Lightest lipids ~860 kg m-3 • Average cell density is rarely less than ~1050 kg m-3
Sinking and Entrainment in Natural Turbulence • Tendency to sink or float (ws) • Propulsion (us) • Velocities of the water • Horizontal motion increases distance traveled during fall
Loss of Sinking Particles from Turbulent Layers • 95% elimination te/t’=3.0 • 99% elimination te/t’=4.6
Mixing Largest eddy size Resistance to mixing Robustness of gradient
Vertical Structure in the Pelagic • diurnal time-scale • wind time-scale • seasonal time-scale • compare to euphotic zone • mixed layer • thermocline
Spatial Distribution of Phytoplankton - Vertical • non-motile, negatively buoyant planters • positively buoyant plankters • neutrally buoyant plankters • motile plankters
Spatial Distribution of Phytoplankton – Langmuir circulation
Sampling Issues Ecological Reasons In fisheries patchiness leads to very reduced zones of high growth potential (Hobbie, 2000) Small scale patchiness Langmuir circulation Small lake basins Drift interrupted by shallows, margins, islands Basin scale conveyer current Drift of buoyant organisms Patchiness as inverse function to wind speed Large scale patchiness Horizontal mixing time Diffusivity Population change Horizontal Spatial Distribution of Phytoplankton - Patchiness
Additional resources • General concepts: Inland waters and their ecology, by I. A. E. Bayly and W. D. Williams; Textbook of limnology, by Gerald A. Cole; Wetzel texts… • United States. Environmental Protection Agency. Ecological research series ; EPA-600/… • Ecology of harmful algae, by E. Graneli, J.T. Turner (eds.) • The Algae and their life relations; fundamentals of phycology, by Tilden, Josephine E (1935) • Local resources: ESF theses such as:The distribution and density of phytoplankton of Jamesville Reservoir, by Pingel, Patricia A. • Estuarine Science: A Synthetic Approach to Research and Practice Edited by John E. Hobbie, Island Press, Washington, D.C. (2000)