Wetlands are biodiverse ecosystems that provide a wide range of services from food security, climate change mitigation. Healthy and functioning wetlands are crucial for humans through ecosystem services. However, human activities can impact the quality of a wetland’s drainage pattern, pollution concentration, and disrupted flow regimes. Wetlands are estimated to cover a global area almost as large as Greenland, but their area is declining extremely fast. With over 35% losses since 1970, this puts wetland plants and animals in crisis, where a quarter of species are endangered and at risk of extinction (Gardner et al., 2015).
Despite all the ecological benefits wetlands provide, these ecosystems are often neglected and have received little attention from policy-makers, conservationists, and scientists when discussing climate change and biodiversity protection. Many areas globally, such as the mangroves of South-East Asia, the marshlands of South America, and the swamps of Central Africa, are being drained and dammed at higher rates.
The 26th UN Climate Change Conference of the Parties (COP26) took place in Glasgow last fall. All parties involved agreed to accelerate action towards the goals of the Paris Agreement and the UN Framework Convention on Climate Change. Nations lined up to pledge an end to deforestation, and the leaders of more than 100 countries with approximately 85% of the world’s forests agreed to end deforestation by 2030. This agreement is a type of re-signing of a few equivalent promises for ending wetland loss. According to a statement by Achim Steiner, executive director of the United Nations Environment Programme, in over 100 years, human activities have contributed to destroying 50% of the world’s wetlands. A report published by Nick Davidson indicates that wetland loss may have totaled to 87% since 1700 (Davidson, 2014). There has been a much faster rate of wetland loss during the 20th and early 21st centuries, with a loss of 64–71% of wetlands since 1900 (Davidson, 2014). This loss occurs at a faster rate than for any other major ecosystem.
In a paper supported by Intergovernmental Panel on Climate Change (IPCC), author, Hans Joosten, highlights the importance of wetlands as highly space-effective carbon stocks. For instance, peatlands cover approximately 3% of the global land area, but contain more carbon than the entire forest biomass of the world (Joosten, 2015). Drainage of these areas leads to carbon and nitrogen release as greenhouse gases to the atmosphere. Statistical data shows that as a result of 15% of the peatlands that have been drained, the global anthropogenic CO2 emissions were increased by 5% (Joosten, 2015). Additionally, the destruction of these ecosystems decreases the peatlands’ capacity for water purification, flood control, and habitat provision for specialized biodiversity. This only highlights peatlands’ vital role in national climate change mitigation policies.
Wetlands have the ability to store water and release it to maintain river flows after rain events. This sponge-like feature protects us from floods and disastrous storm events. In mid-July 2021, the Kyll river close to the German-Belgian border over-flowed into neighboring towns (Madgwick, 2022). The flooding took more than 220 lives and cost an estimated $40 billion for repairs. The rainstorm that caused the flooding was unparalleled, but there is another hidden contributor to the floods. Land use across Europe has been dramatically changed, and the destruction of natural wetlands limits the capacity to absorb heavy rains, leaving river-side towns vulnerable to flooding events (Madgwick, 2022).
Another unique ability of wetlands is protection against wildfires. Healthy peatlands have the natural ability to hold decaying moss and water to support a living rug of a unique fire-resistant moss called sphagnum. This feature enables these areas to act as a fire break and prevent fires from spreading across a wetland.
Ultimately, all water systems need protection and restoration. It would not be compelling enough if we focused on wetlands rehabilitation alone. These systems work in concert with each other and must be considered in all policies geared towards climate resilience and ecosystem protection.
Sources:
Davidson, N. C. (2014). How much wetland has the world lost? Long-term and recent trends in Global Wetland Area. Marine and Freshwater Research, 65(10), 934–941. https://doi.org/10.1071/mf14173
Gardner, R., Barchiesi, S., Beltrame, C., Finlayson, M., Galewski, T., Harrison, I., Paganini, M., Perennou, C., DE, P., Rosenqvist, A., & Walpole, M. (2015). State of the world’s wetlands and their services to people: A compilation of recent analyses. Ramsar Briefing Note No. 7. Gland, Switzerland: Ramsar Convention Secretariat. Retrieved from: http://dx.doi.org/10.2139/ssrn.2589447
Joosten, H. (2015). Peatlands, climate change mitigation and biodiversity conservation. Nordic Council of Ministers. Retrieved from: https://www.ramsar.org/sites/default/files/documents/library/ny_2._korrektur_anp_peatland.pdf
Madgwick, J. (2022). Opinion: Germany needs to invest in nature to defend against floods: Deutsche Welle. Retrieved from https://www.dw.com/en/opinion-germany-needs-to-invest-in-nature-to-defend-against-floods/a-60607186