Bodies of water are home to a plethora of natural biodiversity, seen across flora and fauna. This is particularly true for coastal regions and brackish waters, some of which can also act as large carbon stores and sequester carbon dioxide.
Undoubtedly, coastal biodiversity and carbon stores are linked and have unfortunately been significantly depleted over the last century. Therefore, in order to protect our “Life Below Water”, we need to unite in conserving both aquatic biodiversity and our greatest natural carbon stores.
Wellers Impact and its partner, Water Unite, understands the importance of SDG 14 “Life Below Water” and is committed to solving this long term issue through impact investment.
Mangroves act as an important carbon store worldwide and are an important feature of aquatic life that often form a link to different water systems, including marine life. In Africa, Kenya, alongside Tanzania, Madagascar, the Democratic Republic of Congo and Nigeria have important mangrove swamps, the last of which has the largest concentration of mangroves in Africa which spans approximately 10,500km2 (Onyena and Sam 2020).
Alongside sequestering carbon, mangrove trees have ecosystemic roles such as providing habitats for aquatic life, often in areas of high biodiversity and protecting coastlines (Martin et al. 2019). Microplastics and plastics can pollute these brackish water environments which can have numerous devastating ecological effects.
Firstly, microplastics do not decompose naturally in the environment and so are taken up into their environments and are passed through nutrient cycles and food chains. Due to the high levels of biodiversity in brackish environments which contain mangrove trees, this has a ripple effect on a multitude of species.
As mangrove areas are often linked to other aquatic environments through the path of the water, the spread of these pollutants is on a very large scale, which is amplified by the fact that time is not a factor as they do not decompose in the short term.
Although some research has indicated that mangrove swamps can act as filters for macroplastic debris thus preventing it from reaching marine waters, this would result in the mangrove swamps themselves becoming over-polluted by plastics and microplastics. It is by this mechanism that mangrove swamps can become sinks for macroplastics (Martin et al. 2019).
Secondly, mangrove plants act as a natural habitat to much aquatic life, including fish, insects and other small vertebrates. Large plastic debris disrupts these habitats, which can prevent the full use of these habitats for animals and alters the interactions that they have in their environment.
Furthermore, the animals can become trapped in the debris which may restrict their movements, meaning that they could be unable to feed or breathe. Larger predators may accidentally ingest plastic material which can cause suffocation and can lead to anthropogenic-driven death.
Thirdly, microplastics would not be filtered out by mangroves and can be easily ingested by a variety of aquatic life. Studies have indicated that the absorption or ingestion of microplastics is harmful to their health, primarily causing neurotoxicity (chemical-based damage to the nervous system) and oxidative damage (free radicals that can cause damage to cells) (Barboza et al. 2020).
This effect would be seen downstream from the mangrove swamps and would be observed in marine life. Microplastics can also affect the photosynthetic abilities of algae. Algae play a vital role in controlling and monitoring the levels of organic pollutants.
Microplastics are an inorganic pollutant that can prevent the filtering role of algae and prevent its photosynthetic role which would increase the concentration of carbon dioxide in the water, as well as increasing the number of organic pollutants found in addition to the presence of inorganic microplastics.
These characteristics give mangrove swamps a key role in preventing or slowing down natural and inorganic pollution.
However, the risks that microplastics pose through toxicity and the related increase in the concentration of other pollutants will alter the effectiveness and health of mangroves (Martin et al. 2020), causing even sub-lethal effects (Gall and Thompson 2015) and can alter the concentration of carbon dioxide in the natural environment, thus contributing to global warming.
These ecological catastrophes can be mitigated. Preventing as much plastic as possible from settling in these environments is key to protecting our “Life Below Water”.
Water Unite is actively playing a role in controlling the plastic pollution found in Kenya, India and Mozambique.
Their programme in Kenya, called Gjenge Makers, employs local people as plastic pickers who pick up discarded plastic debris, which is recycled to be used as sustainable and affordable construction materials for buildings and houses.
This directly removes the plastic from the environment and prevents many negative chain reactions involving plastic pollution, which can easily spread to other aquatic life due to the nature of the connectivity between water systems.
Furthermore, this programme offers employment to people who may not have otherwise had an income, which supports SDG 1 “No Poverty” and SDG 8 “Decent Work and Economic Growth”.
When considering “Life Below Water”, it is important to recognise the value of water reserves to people within communities who may not have access to safe drinking water or have very limited access to water.
For example, Cape Town suffered a severe drought between 2015 and 2018 as a result of an El Niño event, resulting in three dry winters. This led to diminished watersheds, as Cape Town’s dam levels fell from 71.9% (2014) to 21.4% (2018).
Not only did this largely impact aquatic life, including fish, other vertebrates, and the invertebrate population, it impacted 4 million people (40% of whom live below the poverty line), which increased the divide between different economic classes.
The agricultural and tourism industries particularly suffered due to the reliance of both on-water supplies for crops and marine life, which also led to an inflation of the price of food (The Nature Conservancy 2016) (TIME 2020).
Water Unite partnered with The Nature Conservancy in order to help to address this issue and to create a blended financing strategy to raise the required funds to help tackle this issue.
This led to the establishment of the Cape Town Water Fund, a water governance structure. Furthermore, The Nature Conservancy tackled this problem from an ecological perspective as they removed non-native trees domestically which used up a significant amount of the available water. This allowed the natural environment to flourish.
To find out how you can invest to make a difference, contact us for more details.
Wellers Impact is a UK-based, FCA-Regulated Impact Investment Manager which works to unlock community-focused impact through SDG-focused impact investing. Through innovative investment models that utilise fair economics, Wellers Impact originates investment opportunities across three core business activities; real estate developments in partnership with local land-owning not-for-profits in East Africa, financial support for agriculture firms and supply chains globally through sustainable development finance and direct investment into private water, sanitation and plastics recycling firms globally. Investment involves risk. Suitable for Sophisticated, Professional and High Net Worth Investors only.
Barboza, L., Lopes, C., Oliveira, P., Bessa, F., Otero, V., Henriques, B., Raimundo, J., Caetano, M., Vale, C. and Guilhermino, L., 2020. Microplastics in wild fish from North East Atlantic Ocean and its potential for causing neurotoxic effects, lipid oxidative damage, and human health risks associated with ingestion exposure. Science of The Total Environment, 717, p.134625.
Gall, S. and Thompson, R., 2015. The impact of debris on marine life. Marine Pollution Bulletin, 92(1-2), pp.170-179.
Kinsey, D. and Hopley, D., 1991. The significance of coral reefs as global carbon sinks— response to Greenhouse. Global and Planetary Change, 3(4), pp.363-377.
Martin, C., Almahasheer, H. and Duarte, C., 2019. Mangrove forests as traps for marine litter. Environmental Pollution, 247, pp.499-508.
Martin, C., Baalkhuyur, F., Valluzzi, L., Saderne, V., Cusack, M., Almahasheer, H., Krishnakumar, P., Rabaoui, L., Qurban, M., Arias-Ortiz, A., Masqué, P. and Duarte, C., 2020. Exponential increase of plastic burial in mangrove sediments as a major plastic sink. Science Advances, 6(44), p.eaaz5593.
Onyena, A. and Sam, K., 2020. A review of the threat of oil exploitation to mangrove ecosystem: Insights from Niger Delta, Nigeria. Global Ecology and Conservation, 22, p.e00961.
TIME.com. 2020. 'I Knew We Were In Trouble.' What It's Like To Live Through Cape Town's Massive Water Crisis. [online] Available at: <https://time.com/cape-town-south-africa-water-crisis/>.
The Nature Conservancy, 2016. Sub-Saharan Africa's Urban Water Blueprint. [online] Nairobi, Kenya: The Nature Conservancy. Available at: <https://www.nature.org/content/dam/tnc/nature/en/documents/Urban_Water_Blueprint_Region_Africa_Aug2016.pdf>.
Onyena, A. and Sam, K., 2020. A review of the threat of oil exploitation to mangrove ecosystem: Insights from Niger Delta, Nigeria. Global Ecology and Conservation, 22, p.e00961.
TIME.com. 2020. 'I Knew We Were In Trouble.' What It's Like To Live Through Cape Town's Massive Water Crisis. [online] Available at: <https://time.com/cape-town-south-africa-water-crisis/>.
The Nature Conservancy, 2016. Sub-Saharan Africa's Urban Water Blueprint. [online] Nairobi, Kenya: The Nature Conservancy. Available at: <https://www.nature.org/content/dam/tnc/nature/en/documents/Urban_Water_Blueprint_Region_Africa_Aug2016.pdf>.