Three ways wetlands can influence climate change

By Isis Palay

In 2015, villagers living around Myanmar’s Irrawaddy delta watched the storm clouds roll in. Cyclone Komen triggered some of the worst flooding the region had ever seen, submerging the delta and affecting its delicate ecosystems and biodiversity. The rains altered the makeup of the delicate wetland ecosystem impacting villagers’ food supply, and increasing the risk of flooding.

Wetlands, which cover six percent of the worlds’ surface and are biodiversity hotspots, are under threat from climate change. Climate change could change wetlands forever, but in turn, wetlands can also help to mitigate the impact of climate change.

• Wetlands regulate, capture and store greenhouse gases. Their dense vegetation, algal activity and soils can regulate processes such as decomposition which generate greenhouse gases (GHG). In addition, some types of wetlands might be more efficient at capturing atmospheric carbon than rainforests. The world’s largest tropical wetland in the Pantanal, South America is also one of the most important terrestrial carbon sinks. But, with deforestation, forest fires, construction and agricultural drainage, these precious carbon stores are being degraded with a resulting increase in carbon emissions.
• Wetlands can release carbon dioxide too. A key concern is that if the huge amounts of carbon that are stored in wetlands are released as a consequence of human activities, it will contribute to global warming. This is indeed what is happening through the destruction of peatlands in Indonesia. Also, the warming of soils in wetlands can emit methane, a gas that is 25 times more potent than carbon dioxide in terms of greenhouse effect. Warmer soil temperatures are one of the factors that aggravate methane release, which is a concern when we consider global warming is causing temperature rise.
• Wetlands provide natural protection and can help communities with climate mitigation and adaptation. Some wetlands provide a buffer, and other coping strategies to protect against storm surges and flooding, which, thanks to climate change, are now more frequent. Urban wetlands can help absorb excess rain fall, protecting cities from storms and surges, while mangroves are a natural coastal barrier; their roots knit together, trapping sediment and preventing coastal erosion which strengthens the shoreline. Some wetlands may reduce the devastating impact of floods, while others may help to supply water during droughts. Wetlands also provide other services that may boost local livelihoods and help communities adapt to climate change. With the melting of glaciers, they can become an important source of freshwater, since the plants and microorganisms that live in wetlands may help purify water from pollutants and excess nutrients. In addition, many wetlands sustain local communities by supporting fisheries, agriculture, livestock and the production of fuel, and are therefore part of the solution to the food security issues that climate change will catalyze in the coming decades.

As a signatory to the Ramsar Convention on wetland protection, IWMI believes in the importance of wetlands for climate mitigation and adaptation strategies. Through its research, IWMI works on several fronts, encouraging and promoting better management and governance practices of wetlands around the world. Through irrigation infrastructure improvements in Myanmar, new community governance frameworks for wetlands, and research on wetlands’ potential for agriculture in Africa, IWMI is helping to develop new ways to better protect these key ecosystems.

With improved resource stewardship, and with higher awareness levels on the importance of key ecosystems such as wetlands, efficient climate mitigation and adaptation strategies can be adopted, and communities and their environment can thrive.