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CH3041
EUTROPHICATION
• Eutrophication “well nourished”
- refers to the condition of a lake
or reservoir where there is excess
algal growth which leads to
deterioration of the body of water.
• Step 1: Input of excess nutrients
(N, P, K) from watershed or sewage.
• Step 2: Large surface biomass produced.
• Step 3: Dead biomass accumulates at the
    bottom where nutrient recycling occurs.
• Step 4: Bottom fills in & swamp develops.
• Normally P is limiting, this is the major initiator of Step1
T oC
DO mg/L
Torrens Lake (Adelaide) sediment trap which has phosphate at dramatic levels sufficient to trigger
Blue-green algae outbreaks. Lake is periodically flushed (2005).