Climate Impacts of Rewilding

By Izzy Williamson

What is rewilding?

As a contemporary form of conservation and ecological restoration, rewilding has gained heightened attention and critical discussion in recent years. In being defined by Rewilding Europe as “letting nature take care of itself, enabling natural processes to shape land and sea, repair damaged ecosystems and restore degraded landscapes”1, rewilding aims to restore what has been lost and protect what is left. More specifically, the rewilding concept orients upon the ‘three C’s’, also known as:

  • Cores: core protected areas where human activities are curtailed.
  • Corridors: protected wilderness areas which are connected to allow migration and movement.
  • Carnivores: large predators or keystone species which regulate the ecosystem and ensure stable relationships throughout the food chain.
Climate Impacts of Rewilding

Where is rewilding done?

  • Geographically: Although first originating in North America, rewilding has recently expanded to Europe, Asia, Africa, and South America. Europe and North America still remain key hotspots however.
  • Locally: In being applied at local, regional, and national scales, rewilding tends to be located in areas where the ecosystem has been perturbed in some way. This might include environments where biodiversity has diminished, or land has been left unprotected or abandoned over time.

How is rewilding done?

Although approaches to rewilding differ cross-contextually, most projects tend to involve species reintroduction and passive management. Usually, this requires human intervention at the beginning to help kickstart and facilitate the rewilding process. These actions may include:

  • Protecting, expanding, and connecting ancient woodlands
  • Dyke/dam removal
  • Ground preparation
  • Direct seeding
  • Species reintroduction
  • Nesting protection
  • Reducing high populations of grazing animals
  • Removing fishing pressures and increasing marine protection
  • Restoring wetlands and introducing beavers
  • Connecting habitats

As well as the above ecological support, technical support is often provided to help existing and potential businesses adapt to the landscape change. This can include planning, training, finance, and marketing expertise.

Climate Impacts of Rewilding

Why do rewilding?

Ecological value
In developing self-sustaining ‘mosaic landscapes’ which host a diverse array of species, rewilding can help environments build resilience towards ecological risks – such as pollution and climate change. Rewilding helps do this through:

  • Protecting and reintroducing endangered species. This includes a focus upon those higher up the food chain, such as beaver, elk, ibex, wild horses and wolves. Their introduction can trigger multiplier effects throughout the entire ecosystem.
  • Protecting, restoring, and creating new woodlands. Trees not only provide habitats for wildlife, but also sequester atmospheric carbon through photosynthesis, which reduces air pollution locally, while also helping mitigate anthropogenic climate change.
  • Developing peatbogs and marshlands. These areas provide a wetland habitat for animals and also form a natural flood defense.
  • Creating natural ‘corridors’ between environments. As climate zones shift northwards, natural corridors will enable species to migrate and habitats to adapt, serving to support species resilience within changing climatic conditions.

Socio-economic value

  • Tourism. Nature tourism can create jobs, which through generating income for locals, can trigger multiplier effects for entire communities – including the potential for sustainable economic development. This can prove especially consequential in remote locations which are less prosperous or attractive for investors.
  • Entrepreneurship. Rewilding can provide locals the opportunity to create and sell cultural products. While this can provide income, it can also educate and engage visitors with regard to local heritage and the importance of conservation.
  • Natural resilience. In providing clean air and water, natural flood defenses, and an active carbon sink, rewilding offers a form of protection against climate change, including extreme weather events. This in itself represents immense socio-economic value given the associated risks to infrastructure and livelihoods.
Climate Impacts of Rewilding

Human health and wellbeing

  • Health. Human connection with wild nature has proven health benefits to both physical and mental wellbeing, and is seen as a way to help overcome ‘nature-deficit disorder’ in children and adults1.
  • Wellbeing. Reconnecting communities with nature – both urban and rural – can cultivate a shared sense of pride and care for the environment. Such engagement can sponsor positive attitudes towards wildlife protection and conservation, representing potential to spillover into everyday behavior.

What are the concerns?

As a relatively recent concept, with most projects still in infancy, questions over where, how, and if, rewilding should be done has been a topic of intense debate. The largely unproven benefits, and difficulties over monitoring have exacerbated these concerns. Key points of contention include:

  • Ecological risk. Introducing (non-native) species potentially from abroad, risks bringing in disease or unintended interactions within local environments.
  • Socio-economic cost. In preventing the development of productive farmland, rewilding represents an opportunity cost for farmers and landowners. This also raises environmental concerns given this could increase reliance upon carbon-intensive imports to feed a growing population in the UK.
  • Commerciality. If the rewilded land is used for commercial activity such as tourism and local business, there is the risk that incentives begin to deviate. This could involve greenwashing and unsustainable business practice.
  • Conflict. Land management projects tend to involve a wide-range of stakeholders, including tourists, farmers, environmentalists, hunters, entrepreneurs, and local residents. Competing interests can cause socio-political issues in discussions upon application and monitoring.

Where next for rewilding?

Going forwards, rewilding organizations aim to scale up projects as quickly as possible. In the UK, Rewilding Britain aims to rewild at least 5% of total land. To achieve this ‘amplification process’, experts intend to:

  • Educate. Provide support, knowledge, and expertise to landowners and foresters.
  • Network. Develop global networks with scientists, academics, and policymakers via the Rewilding Network.
  • Communicate. Develop communications and marketing material to engage the public, government, and private sector.
  • Pressure. Target the European Commission to develop legislation which advocates and supports rewilding processes.
Climate Impacts of Rewilding

Rewilding and Tree Planting Health

Opposing or complementary?

There are varied perspectives as to if and how rewilding and tree planting should interact. Some environmentalists perceive the two as opposing conservation techniques given that tree planting can be considered to curtail the natural dynamics within a wild space, and in doing so, limit ecosystem diversity and richness . However, most environmental organisations consider tree planting as a complementary, and often necessary support mechanism to rewilding, especially at early stages of development . While natural regeneration is often a sustainable way to build ecosystem resilience, structural support from tree planting and vegetation clearing can be highly beneficial to facilitating and maintaining healthy woodland growth.


Tree planting

Rewilding
Type of coverage Forest/woodland. ‘Mosaic landscape’ including native woodland, peatbogs, scrub, heaths and grasslands.
Human involvement ‘Anthropocentric’ approach to conservation where humans are external to nature and in control of it. ‘Biocentric’ approach to conservation where humans are situated within nature and co-exist.
Time scale & size Shorter-term, and often smaller-scale projects involving species-focused management. Longer term, large-scale projects which take a more holistic view of the landscape.
Approach Active planting, management and maintenance of chosen trees. Self-regulation is encouraged and natural resilience is developed over time.
Cost Greater cost per area due to more human intervention and resources required. Cheaper and technically easier option as nature is left to its own devices[1].
Carbon sequestration Woodland/forest has the largest carbon sequestration rate – both above and underground.

The Woodland Carbon Code has estimated sequestration rates for differing tree species[2]. Listed below are some tree species and their total carbon sequestration rate over the course of 20-25 years.
Estimates are made for non thinned high yielding species:
– Corsican Pine – 480 tCO2e/ha
– Douglas Fir – 655 tCO2e/ha
– Hybrid Larch – 437 tCO2e/ha
– Norway Spruce – 394 tCO2e/ha
– Oak – 448 tCO2e/ha
– Mixed Conifer – 394 tCO2e/ha

Average mixed woodland: 18.5tCO2e/ha/year.

Rewilded areas provide less effective carbon sequestration as natural regeneration can be unpredictable and slow. This is due to poor dispersal and colonisation abilities of some species. Early successional native tree species such as birch and willow are typically the first colonisers – which have comparatively lower sequestration rates[3].
It is also more difficult to measure carbon stock in rewilding projects due to species diversity and mixed land use. Rewilding Britain estimates that through supporting native woodland, re-establishing grassland, as well as restoring peatbogs and heath, sequestration would average at:
7.83 tCO2e/ha/year[4].

A Graphical Perspective5

Finding a balance

In some locations, rewilding can encourage resilience to disease, diversify ecosystems, and promote long-term carbon sequestration. In other locations however, managed tree planting can be a more effective and efficient mechanism through which to sequester carbon. This is especially relevant in areas where rewilding is unlikely to occur, such as urban parks or grasslands which are far from natural seed sources .

Given that greenhouse gas emissions are growing exponentially, and the associated ecological and human repercussions are now increasingly visible, the speed and scale at which conservation happens needs to be re-addressed. Both tree planting and rewilding offer invaluable ways to help achieve our ambitious climate targets, and potentially prevent us from climate chaos.

Climate Impacts of Rewilding

For more information about the Forest Canopy Foundation, visit the website by clicking the button to the right.

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Bibliography

  1. Lewis et al (2019) Restoring natural forests is the best way to remove atmospheric carbon. Available at: ttps://www.nature.com/articles/d41586-019-01026-8
  2. Woodland Carbon Code (2021) Available at : https://woodlandcarboncode.org.uk/standard-and-guidance/3-carbon-sequestration/3-3-project-carbon-sequestration
  3. Barsoum, N. and Henderson, L. (2016) Converting planted non-native conifer to native woodlands: a review of the benefits, drawbacks and experience in Britain. Available at : https://www.forestresearch.gov.uk/research/converting-planted-non-native-conifer-to-native-woodlands-areview-of-the-benefts-drawbacks-and-experience-in-britain/
  4. Rewilding Britain (2021) Why we need rewilding. Available at : https://www.rewildingbritain.org.uk/explore-rewilding/what-is-rewilding/why-we-need-rewilding
  5. Lewis (2016) The Paris Agreement has solved a troubling problem. Available at: https://www.nature.com/articles/532283a

Further References

  • https://www.rewildingbritain.org.uk/
  • https://rewildingeurope.com/
  • https://truenaturefoundation.org/what-is-rewilding/
  • https://treesforlife.org.uk/into-the-forest/rewilding/
  • https://www.annualreviews.org/doi/pdf/10.1146/annurev-environ-102014-021406
  • https://lcon.org.uk/2020/02/03/missing-the-wood-for-the-trees-tree-planting-vs-rewilding/
  • https://www.sciencedirect.com/science/article/abs/pii/S0016718514002504
  • https://science.sciencemag.org/content/364/6438/eaav5570.abstract
  • https://s3.eu-west-2.amazonaws.com/assets.rewildingbritain.org.uk/documents/Rewilding-and-Climate-Breakdown-a-report-by-Rewilding-Britain.pdf
  • https://ww2.rspb.org.uk/Images/Forestry%20and%20climate%20change%20report%20Feb%202020_tcm9-478449.pdf
  • Barsoum, N. and Henderson, L. (2016). “Converting planted non-native conifer to native woodlands: a review of the benefits, drawbacks and experience in Britain.” Forest Research, https://www.forestresearch.gov.uk/research/converting-planted-non-native-conifer-to-native-woodlands-areview-of-the-benefts-drawbacks-and-experience-in-britain/
  • http://publications.naturalengland.org.uk/publication/5419124441481216
  • Marrs, R. et al, 2019: ‘Experimental evidence for sustained carbon sequestration in fire-managed peat moorlands’, Nature Geoscience, 12, 108-112. https://www.nature.com/articles/s41561-018-0266-6
  • Lamb, A. et al, 2016: ‘The potential for land sparing to offset greenhouse gas emissions from agriculture’, Nature Climate Change, 6, 488-492 https://www.nature.com/articles/nclimate2910, Supplementary Info, p. 15