4.4.7—Eutrophication and ecosystem services

Syllabus
First assessment 2026
Objective
4.4.7
Level
HL

Turn Ecological Change into Service Loss

Pollution becomes a social cost when an ecological change removes food, recreation, health protection or cultural services.

Low oxygen lowers fish survival; turbidity reduces recreation; toxic blooms threaten drinking water and livestock; treatment and monitoring costs rise. Identify who experiences each loss.

A fishery closure protects health but removes income from fishers, while residents may gain safer water.

Services distribute costs and benefits unevenly; one measure cannot represent all impacts.

An ecosystem service is not only a market price; health, culture and recreation also count.