Once again, the world is celebrating World Environment Day (WED) 2021 on June 5. This year WED promotes #GenerationRestoration tagline aiming to enhance our generation to support peace with nature through ecosystem restoration. Quoting Geneva Environment Network, ecosystem restoration means assisting in the recovery of ecosystems that have been degraded or destroyed, as well as conserving the ecosystems that are still intact. One of the most highly damaged ecosystems that need to be restored is coastal ecosystems which has huge roles in absorbing and storing carbon.

Based on the 6th ASEAN Energy Outlook (AEO6), energy-related Green House Gas (GHG) emissions in ASEAN countries were about 1,686 Mt CO₂-eq in 2017. In the Baseline Scenario, they reach 2,228 Mt CO₂-eq by 2025, then almost double again to 4,171 Mt CO₂-eq by 2040. If there are no significant effort in reducing GHG emissions which accelerate climate change, economic losses could appear up to 11% of GDP by 2100. Also, climate change can increase global temperature and raise risk of natural disasters such as storms, floods and droughts. The impacts of climate change include decrease of agricultural productivity, increase demand for energy and other resources, damage to coastal ecosystems, loss of terrestrial forest cover and biodiversity, increase risk of death from heat and diseases transmitted through water or other vectors, and loss of labour productivity. Therefore, it is important to develop efforts in reducing GHG emissions one of which is enhancing the capability of ecosystems to sequester and store carbon through restoration of degraded ecosystems.

Blue carbon is a term that refers to the carbon that is absorbed, stored, and released by coastal and marine ecosystems. Coastal blue carbon ecosystems (mangroves, seagrass beds and brackish marshes) have an important role in carbon sequestration and storage in the long term, thereby helping to mitigate the impacts of climate change. Measured within the same area, coastal ecosystems are more efficient at storing carbon than most terrestrial forests. Mangrove forests are able to absorb up to four times more carbon and store up to ten times more carbon than terrestrial forests. Around 726 tonnes of coal emissions are offset by one hectare of mangrove. On the other hand, the destruction of mangrove forests can release large amounts of carbon dioxide due to the loss of mangrove trees and the breakdown of soil carbon.

Mangrove forests in Southeast Asia region were lost at an average rate of 0.18% per year between 2000-2012. Mangrove loss in Myanmar mostly driven by rice agriculture, while oil palm expansion is the main cause in Malaysia and Indonesia. Moreover, the exponential increase of world population growth has led to increase in land demand. The phenomenon of unsustainable land use change is also a major driver of deforestation and forest degradation. Changes in land use, especially those related to agricultural intensification for economic purposes, are known to cause changes in the type of cover and spatial structure of vegetation.

Efforts in restoring mangrove forests have been done in many Asian countries such as Indonesia, Bangladesh, Sri Lanka, and Vietnam. However, there are often errors in restoration implementation. For example, planting of seedlings in naturally bare mudflats or hydrologically inappropriate area. Furthermore, the local communities have not included in project planning and implementation in many of the mangrove restoration projects in Asia, whereas engagement from local communities is crucial for the success of large-scale restoration projects in heavily populated areas. Failures in Asian mangrove restoration efforts caused by biophysical and social factors. Also, better restoration policies are essential to conserve mangrove ecosystems.

It is our time to stand up and act to save our coastal and marine ecosystems by keeping our coasts and oceans clean and support local restoration project. As a #GenerationRestoration we must protect our ecosystems to ensure the quality of its environmental services in order to enhance not only the wellbeing of our generation, but also the future of our children.

References

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Lee, S., Hamilton, S., Barbier, E., Primavera, J., Lewis III, R. 2019. Better restoration policies are needed to conserve mangrove ecosystems. Nature Ecology & Evolution volume 3, pages870–872 (2019).

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Spalding M, McIvor A, Tonneijck FH, Tol S and van Eijk P. 2014. Mangroves for Coastal Defence; Guidelines for Coastal Managers & Policy Makers. Wetlands International and The Nature Conservancy. 42 p

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