IB Biology HL 4.2.6 Sustainable resource harvesting Question Bank
Practise IB Biology SL/HL 4.2.6 by applying sustainable resource harvesting concepts to exam-style questions.
- Syllabus
- First assessment 2025
- Course
- Biology HL
- Level
- HL
Practise IB Biology SL/HL 4.2.6 by applying sustainable resource harvesting concepts to exam-style questions.
The diagram shows levels of DDT, a pesticide, in an aquatic food web in Lake Kariba, Africa. Numbers represent ppm (parts per million) of DDT in fat tissue.

Discuss the impact of overfishing in Lake Kariba and how sustainable harvesting of resources can be assessed.
Impact: [2 max]
a. overfishing can disrupt food chains/webs/ecosystems;
b. named example from the diagram;
c. decrease biodiversity / OWTTE;
Assessing: [2 max]
d. monitoring/measuring that the rate of harvesting of species is lower than the rate of replacement of species/OWTTE;
e. monitoring/enforcing application of regulations;
f. monitoring population size (over time)
OR
monitoring biodiversity (over time);
e. Accept monitoring of regulations, e.g., size/age of fish, number in a catch,
mesh size of nets, quotas, etc., but not setting of regulations.
4
Marking guidance:
max