ESCI 430: Limnology
Fall Quarter

Course Outline

  1. Limnology: Introduction - background and history, and areas of research
  2. Geomorphology of lakes: lake districts; fate of lakes
    1. Lake-forming processes and examples
      1. Glacial
        1. Lakes associated with existing glaciers; glacial and subglacial pools
        2. Lakes formed near glaciers: periglacial frost-thaw basin; permafrost; ice-wedge casets; pingo
        3. Lakes formed where glaciers existed: glacial drift (outwash and moraine)
        4. Ice block, kettle or pit lakes
        5. Morainic impoundment: lateral moraine; terminal moraine
        6. Glacial scour lakes
        7. Cirque lakes (tarns) / paternoster lakes
      2. Tectonic lakes: graben; epeirogenesis; earthquakes
        1. Landslide lakes
        2. Volcanism: crater lakes; lava depressions
      3. Solution lakes: limestone and salt karst
      4. Fluviatile lakes
        1. Flood plain lakes: levee lakes; oxbow lakes; evorsion (pothole) lakes
      5. Aeolian lakes
      6. Biological agents: bog plants; coral reefs; pitcher plants and bromeliads; water filled tree holes; alligators; beavers; humans: intentional and accidental
      7. Extraterrestrial and unknown: meteorite impact; Carolina Bays
      8. Relict and intermittent lakes; playas
  3. Lake morphology:
    1. Surface dimensions: l; fetch; b; A; L; DL
    2. Subsurface dimensions: z; zm; cryptodepression (zc); V; hypsographic curve; mean z; Thienemann's boundary (18m)
  4. Solar radiation
    1. Heat
      1. Metabolic rate
      2. Thermal stratification: epilimnion; hypolimnion; metalimnion; thermocline; Ainverse thermal stratifications
        1. Annual cycle: amictic; monomictic; dimictic; polymictic; holmictic; meromictic
        2. Chemical meromixis: monimolimnion; mixolimnion; chemocline
          1. Ectogenic
          2. Endogenic: biogenic; cryogenic
        3. Thermal bar
        4. Hypolimnion heating and cooling: solar heating; upwelling; hypolimnetic entrainment
      3. Heat storage capacity: latent heat of fusion
        1. Birgean heat budget: summer heat income; winter heat income; annual heat budget
        2. Sediment heat storage
    2. Light
      1. Aquatic food chain
      2. Measurement: pyrheliometer; spectral discrimination; Secchi disk
      3. As energy: intensity and wavelength; reflection (albedo); refraction; scattering; absorption and transmission; extinction coefficient; PAR
      4. Lake color
  5. Water movement
    1. Surface movements: traveling surface waves; wavelength; wave height
    2. Surface currents: wind; Langmuir circulation
    3. Internal water movements: meta- and hypolimnetic entrainment; surface seiches; internal seiches; under ice
  6. Dissolved oxygen
    1. Solubility: altitude; temperature; salinity; relative saturation; supersaturation
    2. Sources: atmosphere (diffusion); photosynthesis; Photosynthetic quotient
    3. Losses
      1. Respiration: sediment-water microzone; winter ice and snow cover; winterkill; blooms and death of algae
      2. Chemical oxidation: hypolimnion
    4. Lake typology: orthograde curve; clinograde curve; positive heterograde curve; negative heterograde curve; horizontal variation and diel cycles
    5. Productivity
      1. Areal Hypolimnetic Oxygen Deficit (AHOD)
      2. Light-dark bottles; carbon 14
    6. Primary production: light-dark bottle method; diel changes
    7. Production rates: maximum rate: in upper epilimnion, no distinct maximum, epilimnetic and metalimnetic peaks, meta- or hypolimnetic peak; photoinhibition
  7. Redox potential: Eh
    1. O2 link
    2. Electroreactive elements: iron; nitrogen; sulfur; carbon
    3. Monimolimnia; bogs; Mortimer's SRP
  8. Utilization of inorganic carbon
    1. Sources: free CO2, H2CO3, HCO3, CO3
    2. Relation to pH
    3. Daily and seasonal cycles
    4. Carbon and productivity; marl formation
    5. Competition with colloids
  9. Phosphorus
    1. Forms: inorganic and organic; orthophosphate; particulate versus soluble; adsorption and colloids
    2. Distribution: epilimnion vs. hypolimnion
    3. Measurement: total reactive phosphate (TRP); total phosphorus; total soluble phosphate (TSP); biologically available phosphorus (BAP); relation of TSP and BAP in eutrophic waters; relation of TRP and BAP in oligotrophic waters
    4. Cycle: terrestrial and aquatic; solubility; transport in insoluble forms; effect of oxygen; sediment exchange
      1. Vertical distribution: pelagic recycling; internal loading; external loading; sedimentation and chemical precipitates; seasonal variation in concentrations; turnover time; Mortimer's Sediment Releasing Phenomenon (SRP)
      2. Availability: sediment water exchange; macrophytes; benthos
  10. Nitrogen
    1. Forms: dissolve organic compounds, N2, NO2, NO3, NH3/NH4+
    2. Mobility: soil and substrate, vegetation
    3. Availability to plants
    4. Effects of forms on organisms: toxicity and supersaturation
    5. Cycling: nitrification, denitrification, ammonification, mineralization, fixation
    6. Sources: precipitation, runoff, photochemical, electrical
    7. Losses: outflow, reduction, sedimentation
    8. Seasonal pattersn
    9. Vertical distribution in water and sediment of stratified eutrophic and oligotrophic lakes
  11. Trophic state
    1. Carlson's Trophic State Index
    2. Wollenwider's criteria - phosphorus loading vs. depth
  12. Biological zonation
    1. Major regions: littoral zone, pelagic or limnetic zone, profundal zone, benthic zone
    2. Communities in each, e.g. aufwuchs and periphyton, epibenthos and infauna
  13. Limnetic communities
    1. Seston: plankton and tripton; size vs. productivity
    2. Trophic levels
    3. Trophic cascade: top-down vs. bottom-up
    4. Phytoplankton
      1. Major groups
      2. Standing crop versus productivity; inverted biomass pyramids
      3. Adaptations to three basic problems
      4. Seasonal patterns: blooms
      5. Vertical and horizontal patterns
      6. Phosphates: luxury consumption
      7. Silica
        1. SiO2 in diatom frustules
        2. Cycle: sources; recycling
      8. Iron
        1. chelation; Cyanobacteria and siderophores
        2. cycles with phosphate
    5. Zooplankton
      1. Four major groups - rotifers, cladocera, copepods, protozoa
      2. Biomass and production
      3. Trophic levels of major groups
      4. Cyclomorphosis
      5. Parthenogenesis, amictic and mictic females, and diapause
      6. Diel vertical distribution and horizontal distribution (shoreline avoidance)
  14. Benthos
    1. Epibenthic and infauna
    2. Life cycles
    3. Below profundal zone
      1. Major groups of organisms
      2. Adaptations to physical and chemical conditions
      3. Heterogeneous distribution; food and seasonal feeding cycles
    4. In littoral zone
      1. Major groups of organisms
      2. Macrophyte function and adaptation
      3. Species diversity, density, productivity
  15. Littoral zone
    1. Macrophytes
      1. Kinds (major ecological groups)
      2. Characteristics: e.g. heterophylly
      3. Productivity
      4. Adaptations to environmental conditions
      5. Reproduction and proliferation: turions
      6. Daily and seasonal cycles of productivity
        1. CO2 and pH
        2. Marl formation
    2. Gradients in temperature and DO
    3. Competition with other primary producers
    4. Invertebrate roles
  16. Fish
    1. Trophic levels: relation to whole-lake production
    2. Ecological role - guilds
    3. Life cycle, areas of feeding, and concept of ecologically distinct organisms
    4. Types and methods of feeding: planktivorous, piscivorous, detritivorous/benthivorous, herbivorous; opportunism
    5. Biomanipulation and the trophic cascade
  17. Lake ontogeny
    1. Photosynthesis to respiration ratio: eutrophic and oligotrophic vs. dystrophic
    2. Succession and bog formation
    3. Ecological characteristics of wetlands
      1. Primary production vs. Heterotrophy
      2. Rheotrophic vs. Ombrotrophic
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