IB Environmental Systems: Water & Aquatic Systems Revision

Water & Aquatic Systems is a core part of IB Environmental Systems. Revise the key concepts and common mistakes below, then lock them in with the free games.

Key concepts

Hydrological cycleEvaporation, transpiration, condensation, precipitation, runoff, infiltration, groundwater flow.

AquiferPermeable rock storing groundwater; recharged by infiltration; over-abstraction lowers water table.

Maximum sustainable yieldLargest catch that can be taken indefinitely; in the logistic model it is reached by holding the stock at half the carrying capacity.

EutrophicationNutrient enrichment causes algal blooms, decomposition, hypoxia; collapse of aquatic ecosystem.

AquacultureFarmed fish/shellfish; ~50% of fish consumed (FAO 2020); concerns about effluent and disease.

Cod collapseNewfoundland Grand Banks cod fishery collapsed 1992; moratorium imposed; lesson in overfishing.

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Water & Aquatic Systems

Key concepts

Practise Water & Aquatic Systems — free games

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