1. The seasonal dyanamics of the phytoplankton in lakes Temperature adaptations of different algal groups Thermal stratification, sinking rates and nutrient dynamics Food-web interaction—effects of grazing zooplankton mid-summer low biomass community shifts to inedible forms

2. Early spring—diatoms dominate--under cold temperatures and low light conditions plenty of nutrients in the well mixed water column Summer—lake warms up, thermocline forms diatoms fall out of the mixing layer—low viscosity and low mixing depth Asterionella the only diatom that can still hang in. Mid-summer—nutrients lost from mixed layer (sedimentation of algae), warm temperatures favour green algae, and zooplankton herbivory is high favouring fast growing small species eg Chlorella Late summer—herbivores eliminate edible species, large colonial cyanobacteria dominate eg. Microcystis Fall—water cooling, thermocline breaks up, mixing depth increases, nutrients increase, diatoms dominate Winter—low light and cold temp low biomass

3. Cyclotella:centric diatom (around 20 microns) and Stephanodiscus (around 50 microns) Usually abundant in spring plankton

4. colonial diatom—elongate cells joined at the base to form stellate colonies Fairly large for planktonic diatoms, each cell 50-70 microns Commonly found in dense blooms during May, prior to the onset of thermal stratification Asterionella

5. Chlorella: a unicellular non-flagellated green algae

6. Copepods Copepod Larvae--Nauplius Cladocera Rotifers Lake Zooplankton

7. Anabaena: cells in large colonies (filaments) with no gelatinous matrix, coiled or straight, heterocysts and akinetes usually present, cells 3-5 microns

8. Colony of Microcystis A common bloom forming cynabacterium that sometimes can be highly toxic Colonial growth pattern—cells embedded in a gelatinous matrix Microcystis: cells in large colonies irregularly arranged within a gelatinous matrix (3b)