Quick questions on Sustainability and Indigenous land management: HSC Earth and Environmental Science Module 8

The ecological footprint estimates the area of productive land and sea needed to supply a person's or nation's resource use and absorb their waste. It is a useful communication tool: it shows that if everyone consumed like an average Australian, several Earths would be needed, highlighting overconsumption. Its limitation is that it is an estimate based on broad assumptions and treats very different impacts as a single area figure, so it indicates scale rather than precise impact.

Life cycle assessment evaluates the environmental impact of a product across its whole life, from raw-material extraction through manufacture, use and disposal (cradle to grave). It prevents misleading conclusions: an electric vehicle has no exhaust emissions but its battery requires mining and energy to make, so a full assessment is needed to compare it fairly with alternatives. Its strength is comprehensiveness; its limitation is that it is data-hungry and depends on the assumptions and boundaries chosen.

The traditional economy is linear: take, make, use, dispose. A circular economy keeps materials in use through reuse, repair, remanufacturing and recycling, designing out waste so that the output of one process becomes the input of another. Australia's container deposit schemes (such as Return and Earn in New South Wales) and growing recycling and product-stewardship requirements move in this direction. The circular economy reduces both resource extraction and waste, though it requires design changes, infrastructure and behaviour change to work at scale.

Explain why life cycle assessment gives a fairer comparison of two products than looking at their use stage alone. [3 marks]

Evaluate the contribution of Aboriginal cultural burning to sustainable land management in Australia. [4 marks]