Preservation, Conservation and Restoration of Ecosystems

Preservation: keeping ecosystems undisturbed

Preservation means protecting an ecosystem in its natural, original state with as little human interference as possible. Areas set aside for preservation, such as national parks and totally protected forest reserves, are kept free from activities like logging, hunting, and development so that the ecosystem remains as close as possible to its untouched condition.

Conservation: sustainable management of resources

Conservation means managing and using natural resources wisely so that they remain available for both present and future generations, rather than leaving them completely untouched. Examples include selective logging, where only mature trees of a certain size are harvested, controlled fishing quotas, and licensed hunting seasons that allow limited, sustainable use of a resource.

Restoration: rehabilitating degraded ecosystems

Restoration means actively repairing an ecosystem that has already been damaged or degraded, bringing it back towards its original, functioning state. Examples include reforestation programmes that replant native tree species on cleared land, rehabilitating polluted rivers, and captive breeding programmes that reintroduce endangered species into a recovered habitat.

How this is examined

SPM questions frequently ask you to distinguish between preservation, conservation, and restoration, since students often confuse the three. A useful way to tell them apart is to ask: is the ecosystem being left alone (preservation), used sustainably (conservation), or actively repaired because it is already damaged (restoration)?

You may also be asked to classify a described action, such as gazetting a forest reserve or replanting mangroves, into the correct category.

Environmental problems these approaches respond to

Preservation, conservation and restoration are responses to real pressures on ecosystems. Deforestation and unsustainable logging destroy habitats and reduce biodiversity, which is why totally protected reserves are gazetted for preservation.

Overfishing and unregulated hunting can wipe out a population entirely, which is why conservation relies on quotas and licensed seasons that keep resource use within sustainable limits. Excess fertiliser running into rivers and lakes causes eutrophication, a build-up of nutrients that triggers algal blooms, depletes dissolved oxygen and kills fish, and restoring an affected waterway usually means cutting the nutrient input and physically removing the algal mass before the ecosystem can recover its original balance.

Sustainability and long-term planning

All three approaches serve the wider goal of sustainability, meeting the needs of the present generation without compromising the ability of future generations to meet their own needs. Burning fossil fuels and clearing forests both raise the concentration of greenhouse gases such as carbon dioxide in the atmosphere, intensifying the greenhouse effect and driving global warming; sustainable practices such as reforestation and controlled resource use help offset these emissions and keep ecosystems functioning for the long term.

Worked exam-style question

Question. A district report describes three actions taken over one year: (i) a 200-hectare area of primary rainforest was gazetted as a wildlife reserve where no logging or hunting is allowed; (ii) a fishing cooperative agreed to a monthly quota limiting the number of fish caught from a nearby lake; (iii) volunteers planted 5,000 native mangrove saplings along a stretch of coastline that had been cleared for aquaculture ponds. For each action, (a) name whether it is an example of preservation, conservation or restoration, and (b) give one reason for your answer.

Model answer. (i) Preservation, the reserve is kept entirely free from logging and hunting, protecting the rainforest in its natural, undisturbed state. (ii) Conservation, the fishing quota allows continued, regulated use of the fish population so that the resource remains available in the future, rather than banning its use altogether.

(iii) Restoration, mangrove planting actively rebuilds an ecosystem that had already been degraded by clearing, bringing it back towards its original, functioning state.

Practice question

Try this. A river that had been heavily polluted by factory waste for years is now the site of a rehabilitation project: engineers have stopped the waste discharge, and biologists are reintroducing native fish species that had disappeared from the river. Identify which of the three approaches this project represents, and explain your answer.

Exam tip

Key terms

These terms describe the environmental pressures that preservation, conservation and restoration all respond to:

• Eutrophication, the build-up of excess nutrients in water, causing algal blooms and oxygen depletion, which restoration projects often have to reverse.
• Greenhouse effect, the trapping of heat by gases in the atmosphere, intensified by deforestation and fossil-fuel burning.
• Global warming, the long-term rise in the Earth's average temperature, linked to a strengthened greenhouse effect.
• Sustainability, meeting present needs without compromising the ability of future generations to meet their own, the goal that conservation practices aim for.

Source:SRC-DSKP-EN

Frequently asked questions

More for Environmental Sustainability