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NotesESS HLUnit 4
IB ESS HL · Unit 4 of 8

Unit 4: Water

Unit 4 of IB Environmental Systems and Societies covers Water. This unit contains 4 topics and 20 sub-topics. Below you'll find free study notes, flashcards, and exam preparation resources for every topic in this unit.

4 topics20 sub-topics
ESS FlashcardsExam technique guide

What Unit 4 covers

HL Unit 4 extends water systems with quantitative water quality analysis, BOD calculations, and more complex evaluation of aquatic food production and water management strategies. HL students must demonstrate greater analytical depth when assessing water resource challenges.

Topics in Unit 4

4.1

Water systems

6 sub-topics

4.2

Water access, use and security

5 sub-topics

4.3

Aquatic food production systems

4 sub-topics

4.4

Water pollution

5 sub-topics

Study tip: Work through the topics in order — each builds on concepts from the one before. Start with notes, then reinforce with flashcards and practice questions.

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Unit 3Unit 5