What is Ecological Restoration?

  Zoe Poulsen     2023-05-28

Written by Zoë C Poulsen. Photos by Caitlin von Witt and Ceinwen Smith

Last year, the United Nations launched the UN Decade on Ecosystem Restoration. Led by El Salvador alongside 70 other countries, a ten-year goal was set to build a global restoration movement to prevent, halt and reverse the degradation of ecosystems worldwide.

But what is ecological restoration? How can it play an integral role in conserving threatened fynbos ecosystems as well as improving biodiversity and sustainability across Cape Town and in other urban areas?

Ecological restoration for healthy ecosystems

Above: Revegetation of Peninsula Granite Fynbos by FynbosLIFE in an urban riverine greenbelt. Photo: Caitlin von Witt

According to the Society of Ecological Restoration (SER), ecological restoration is defined as “the process of assisting the recovery of an ecosystem that has been degraded, damaged, or destroyed”.

Ecological restoration initiates or accelerates the processes involved in recovery of an ecosystem. This is done by creating the conditions necessary for the living components of the ecosystem including plants, animals and microorganisms to recover themselves.

For example, this may include reintroducing species that may have been lost from the ecosystem, clearing alien invasive plants, or mitigating soil erosion.

Passive restoration vs active restoration

Above: A selection of plants for a wetland rehabilitation project. Photo: Caitlin von Witt

Ecological restoration can be divided into passive restoration and active restoration. Passive restoration is usually the method followed when an ecosystem still has seeds that have survived in the ground, which is known as the ‘soil seed bank.’

In this case, the source of disturbance that has been degrading the ecosystem is removed from the system. For example, this may be by putting up fencing to manage grazing livestock or harvesting an alien pine plantation and conducting an ecological burn. The ecosystem is then left to recover naturally.

However, sometimes an ecosystem may have been degraded to the point that other ecological restoration interventions are required. In this case, any species that may have been lost from the ecosystem or have been depleted in numbers through ongoing ecosystem degradation are reintroduced or their numbers at the site are increased.

Above: FynbosLIFE staff Hassan Allabi (left) and James Deacon (right) on a collecting trip for the Tokai SOS Rapid Response restoration project. Photo: Caitlin von Witt

This may be done by collecting and planting seeds from locally indigenous plants. Alternatively, new plants may be grown in cultivation from cuttings or seeds collected from wild plants in nearby natural areas. The new plant babies are then planted out into the restoration area.

Special permits always need to be obtained to collect cuttings and seeds from indigenous plants in natural areas, especially for collecting and growing any threatened plants.

The ecological restoration continuum

Above: Site visit to Haasendaal Nature Reserve to assess restoration potential. Photo: Ceinwen Smith

The resources that are invested into undertaking ecological restoration in a specific area is strategically dependent on the extent to which the site has been degraded and the proportion of species that have been lost from the ecosystem.

We use the ecological restoration continuum as a guideline for determining what restoration interventions should be implemented under what specific circumstances.

In an area where all the indigenous biodiversity has been lost from the ecosystem through, for example, urban development or ploughing fields for growing crops, then the main goal is to reduce the impacts of disturbance on the area, such as by cleaning polluted waterways or addressing soil erosion.

Above: Propagation of material for ecological restoration by FynbosLIFE after a collection trip. Photo: Caitlin von Witt

At the other end of the scale, a site that still has seeds from a range of different plants in the soil seed bank, is large enough for natural ecosystem processes to take place and has recently been designated as a protected area, may be selected for a more comprehensive ecological restoration programme.

The term ‘restoration’ is generally used when a landscape is returned to its original topography, also known as the ‘shape’ of the landscape, as well as having its original species composition.

However, sometimes a new landscape or ecosystem is created that is not the same, such as in post-mining landscapes. In these cases, the terms ‘remediation’, ‘reclamation,’ or ‘rehabilitation’ may be used interchangeably.

Growing locally indigenous

Above: One of the greenhouses at FynbosLIFE used for growing plants for our ecological restoration projects and retail nursery. Photo: Caitlin von Witt

One of the things that makes each ecosystem unique is the groupings of species from plants to insects that live together within it. This is something that varies between ecosystems and even between different sites with the same vegetation type depending on other factors such as altitude, rainfall, or soil type.

In ecosystems with such high biodiversity as the fynbos, this variation occurs at a far higher level, with an extraordinary range of different environmental conditions for plants to grow even in relatively small areas.

Above: Restoration of a threatened species, Steirodiscus tagetes (red-listed as Vulnerable), to a strandveld rehabilitation site. Photo: Caitlin von Witt

The plants from one specific species are genetically different at different sites within the same vegetation type.

This means that when we carry out ecological restoration of an ecosystem, seeds or cuttings from any plants that are reintroduced should be sourced from the nearest natural population to the site.

This is particularly important when there are still some individuals from the species being reintroduced at the site so that the unique genetic makeup of the plants from the site is conserved with the next generation of plants.

Catalysing community action

Above: Schoolchildren learning in a locally indigenous garden through FynbosLIFE’s FundaFynbos programme. Photo: Caitlin von Witt

Restoring an ecosystem and supporting its recovery is a complex process that is informed by scientific research and practice that is undertaken in accordance with national and international policies.

However, some of the most successful ecological restoration programmes are initiated and driven by communities and community groups. Research has shown that biodiverse ecosystems in our backyards in urban areas have a greater ability to support wellness and happiness in our communities.

The educational value of home garden spaces cannot be overestimated as a means to inspire future conservationists.

Working in partnership with an organisation such as FynbosLIFE, you can begin and grow your ecological restoration project in your local park, greenbelt, or protected area. Or you can join hands with us to volunteer at our regular planting events to help bring back biodiversity to our urban spaces.

Further information

Society for Ecological Restoration: https://www.ser.org

UN Decade on Restoration: https://www.decadeonrestoration.org