Restoring Ecosystems (DP IB Biology): Revision Note

Restoring Ecosystems

• Human activities, such as deforestation and overharvesting of resources, can destabilise ecosystems

• Conservation efforts at the ecosystem level aim to improve ecosystem stability by restoring natural ecosystem processes

  • This type of ecosystem restoration project is sometimes known as rewilding

• Restoration strategies may involve

  • Species reintroductions

    • Reintroduction of apex predators will control populations of herbivores and allow the restoration of habitat vegetation; this can increase the diversity of plant species, which will in turn boost overall biodiversity

    • Reintroduction of keystone species can alter the structure of an ecosystem

  • Improving habitat connectivity

    • The establishment of wildlife corridors, e.g. by planting hedgerows throughout farmland, can connect small pockets of habitat

    • When habitats are connected organisms can roam over larger areas; this gives access to more resources and allows populations to increase in size

  • Limiting human influence

    • This may involve preventing the harvesting of resources by, e.g. logging, fishing, or agriculture

    • Ecological management techniques, e.g. controlled grazing or burning, may be used to restore a habitat

Restoration of Hinewai Reserve, New Zealand

• Hinewai Reserve was once farmland, but is now privately owned, with the aim of restoring the natural ecosystem of the area

• Some initial human intervention was involved, with the removal of non-native species, but the area is now managed with minimal human intervention to allow native communities to be restored by succession

• Human activities are limited in the area, though the public can enjoy walking in the Reserve 

 CC BY-SA 4.0, via Wikimedia Commons

Hinewai Reserve in New Zealand is considered to be a an example of successful rewilding