Explain two conflicts that may arise as a result of aquaculture.

“The disposal of waste in the oceans is causing serious harm to people and places.” Discuss this statement.

In each case, award [1] for an identification of the conflict and a further [1] for a development/extension of the conflict.

For example: There may be conflict between aquaculture operators and environmentalists [1] owing to the large volume of fish pellets needed to feed the farmed stock [1]; it takes 2–5 kg of fish pellets to produce 1 kg of farmed salmon [1].

Other possible conflicts may include:

• local/national fishermen/the fish industry due to the introduction of exotic species, eg Atlantic salmon into the Pacific
• environmental health agencies may be worried about the leaking of steroids/faeces/chemicals into surrounding waters, damaging local ecosystems/water sources.

Waste disposal includes radioactive material, oil and chemical waste. Chemical waste includes SO₂ and NO_x (acidification), nitrates (eutrophication/dead zones), plastics (garbage patches), effluent from ships, oil pollution, heavy metals.

Disposal of waste may lead to reduced biological productivity. On the other hand, increased productivity in the short term is associated with nitrates, increased risk of diseases and fatality, reduced growth rates, reduced survival rates. Waste disposal may lead to death of people, falling incomes through reduced fish yields, increased cost of clean-up, unemployment, reduced tourist revenues.

However, the opposing view could be that not all waste causes serious harm to people and places, eg some waste may be disposed of far from populated areas or may be treated/of low toxicity and therefore not especially harmful to ecosystems. For companies involved in clean-up operations/repairs, there may be increased opportunities, rather than any harm.

Good answers may progress beyond a simple description of the problems associated with waste disposal. Good answers may discuss:

• the scale of pollution
• how the impacts vary from place to place and on different types of people
• whether pollution is serious (perspectives may differ)
• whether it is a global problem or a localized one
• whether pollution is a greater problem in different types of ocean (open ocean versus partly enclosed)
• whether management strategies are effective.

At band D, expect some description of waste disposal and the harm that it is causing to people and places.

At band E, expect either a more detailed explanation of waste disposal’s impact on people and places or a structured discussion of the statement that questions the idea of severity and harm.

At band F, expect both of these elements.

Marks should be allocated according to the markbands.