Article written by Georgina van Biljon and edited my Prof. Patricia Holmes 28-02-2025
Like painting something green, there are many shades to choose from. What colour will you choose, and will it serve its purpose?
In this article I discuss a practical example of environmental damage and different scenarios that may be implemented as a response to this. The aim of this article is to guide landowners in making appropriate decisions with regards to ecological repair and stimulating further thinking on this topic.
Where to start?
One needs to consider what outcome (goal) or, in other words, the level of environmental repair you want to achieve.
The following are potential scenarios, based on goals of increasing levels of environmental repair:
Senario 1: Prevent further destruction
Senario 2: Repair the damage so that the river bank looks similar to it's pre-flood condition.
Senario 3: Improve the ecosystem functioning so that erosion can be prevented in the future similar floods, thus decreasing future risk.
Senario 4: Improve the ecosystem over time, so that it resembles a near natural ecosystem that delivers ecosystem services and other benefits (eg. water filtration)
Which ecological repair scenario to choose?
First let’s understand what is meant by “ecological restoration”. According to the Society for Ecological Restoration (SER): ”ecological restoration is the process of assisting the recovery of an ecosystem that has been damaged, degraded, or destroyed”. By contrast, ecological rehabilitation seeks to reinstate a level of ecosystem functioning. The various levels of repair may be depicted as a continuum, as illustrated in the schematic diagram below (Gann et al. 2019).
Restoration practitioners facilitate the process of ecosystem repair by creating the conditions needed for plants, animals and other organisms to carry out the work of recovery themselves. (https://ser-rrc.org/what-is-ecological-restoration/).
Let’s look at the restorative continuum below to help us understand this concept better. This tool was developed by the Society for Ecological Restoration (SER) and includes a range of activities and interventions that can improve environmental conditions and reverse ecosystem degradation and landscape fragmentation. For more tools check: https://www.ser.org/page/Standards-Tools
As one moves from left to right on the continuum, ecological health and quality and quantity of ecosystem services increase.
Practically how to implement the repair scenario?
Scenario 1: To halt destruction and reduce future flood impacts, build berms, gabions, weirs or other protective mechanisms. (REDUCED IMPACTS)
Scenario 2: To repair to pre-flood condition, re-create the riverbank slope or berm that was washed away in the flood. (REMEDIATION)
Scenario 3: To decrease future risk and improve ecosystem functioning, additional actions may include adding further structures to stabilise banks and planting vegetation. The level of improvement depends on how degraded your system is and how much repair is needed to buffer future harmful events. Different methods can be used focusing on the goal and adapted to local conditions. (REHABILITATION)
Scenario 4: To restore towards a near-natural condition, the aim would be to return the ecosystem towards a previously healthy state, or a reference [P M1] ecosystem condition, to provide additional services such as clean water, biodiversity and pollination services (RESTORATION).
Before implementing Scenario 4 interventions, it is advisable to consider the conditions in the wider landscape, i.e., the subcatchment area as a whole that could impact on your planned repair treatments. This is because river systems are complex, especially in lowland areas, supporting multiple users and landowners, with river sections in varying states of degradation.
Higher restoration goals could be leveraged through collaboration with adjacent landowners. For example, sections where the river could benefit from widening of its flood plain to make room for it to flow, connecting corridors of indigenous vegetation from riparian to terrestrial areas, increasing sediment deposition by slowing down the speed of flows, reshaping of river banks, planting/seeding of local indigenous plants, removal of invasive plants from upstream areas and working downstream in the catchment, and fencing off areas to prevent over grazing.
Photo above: River restoration project in Tulbagh, which is returning to a near natural state (+-10years from initial planting).
Some more questions to consider:
What is your long-term goal?
Do you want a quick fixup job or do you want to decrease risk and improve the ecosystem in the long term to provide benefits over many years? When considering rehabilitation goals, one needs to consider that the investment costs may exceed the benefits in the short term. Ecological systems take time to restore before yielding benefits. What are the benefits of restoration? As in having a healthy body, which is an asset that builds resilience against disease. When you are sick, you rest or take some medicine. But that does not keep your body healthy: one also needs to eat healthy food and exercise. Input and management is required for an ecosystem to be healthy and become an asset.
What is the target state I want to work towards?
REDUCED IMPACTS, REMEDIATION, REHABILITATION or RESTORATION.
What are the degradation drivers?
I.e. What is causing the destruction during flood events? What is causing the higher water velocity that leads to bank undercutting and erosion– is it due to channelisation (forcing the river into a narrower, straighter channel)? Once you have understood the cause of the destruction, you can focus your energy and resources in solving the problem.
What are the legal restrictions?
Contact your local irrigation board, CapeNature or restoration specialist[P M1] to see what the legal restrictions are with regards to rehabilitation.
Who is the best person to help with restoration?
One can involve a group of people with a variety of specialities (freshwater specialist, geomorphologist, landscapers, botanists) or a restoration practitioner. There are a few rehabilitation specialists/practitioners in the Western Cape of South Africa. Each has different specialisations and experience. Ask: “What do you specialise in and how much experience do you have?”.
A rehabilitation practitioner or specialist is usually a person who has a whole tool kit of skills (a bit of a jack of all trades in the environmental sector): knowledge in ecological rehabilitation science (ecology, botany, soil science, etc.), has some landscaping background (important for earthmoving and planting), horticulture is a benefit (and having a nursery that grows local indigenous plants that you may not find in other nurseries) and has practical experience with managing teams on site.
Requirements for rehabilitation practitioners and rehabilitation standards are not set in South Africa. This can make it challenging, as you do not know what to expect as an end product. For example: some practitioners may use a variety of plants and inputs, while some only use local indigenous plants. Each action will have a different result (positive or negative) depending on your restoration goal and unique circumstances.
The following standards are overarching restoration standards that are being used globally: https://www.ser.org/page/SERStandards and can guide you in understanding these concepts further.
River rehabilitation is more complicated due to the ever-changing/dynamic nature of the force of water. A riparian (river) rehabilitation practitioner also needs to understand geomorphology and hydrology. If you are rehabilitating fynbos you need a specialist in the Fynbos biome.
Will the proposal serve its purpose?
How does one know that the rehabilitation practitioner’s advice/product quoted for will work on my site? This is not always easy to answer, as each site is unique. Ask the practitioner questions – Have you had success with this rehabilitation method in the past? Please show me an example of this. How is that situation different to mine and how are you going to deal with that? Are any of the methods we are using have risk involved? Please can you try quantifying this risk? What plant survival success rates are you expecting and how can we reduce plant mortality? How can I help make this project a success?
Restoration is a developing field in South Africa. Each site has specific factors that need to be considered (one does not always have the information at hand – like soil health or chemistry) and site factors are driven by ecological processes which are unpredictable by nature. It is a learning process and needs to be adaptive in its management.
Please note that this article’s purpose is to stir interest and stimulate thinking rather than to provide advice on a specific situation. We endorse that decision-making is best guided by on-site consultation by experts in the field. This article was written as part of project: ‘Increasing rehabilitation uptake in the Western Cape SWSA’ funded by WWF South Africa.
For more information or queries, you are welcome to look at our website www.greenintaba.co.za or contact me at: georgina@greenintaba.co.za and if I cannot help, I will try direct you to someone else that may.
References:
Gann GD et al. 2019 International principles and standards for the practice of ecological restoration. Second edition, Restoration Ecology, Volume 27, pp 7-46.
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