Conserving and restoring Mekong’s wetland ecosystems

Photo: Thanapon Piman, SEI Asia. 

Globally, over 80% of wetlands have disappeared since the 1700s, with over 35% of these lost only in the past five decades.

The Ramsar convention has been at the forefront of developing, generating, and delivering new knowledge on wetlands since its inception in 1971.

The Mekong Basin’s wetland ecosystems form the heart of the Indo-Burma biodiversity hotspot, the world's third most biodiverse river system, and one of the most biologically important regions, encompassing over 383,000 km². The Mekong wetlands comprise high-altitude wetlands in the Lancang River headwaters in China, extensive floodplain wetlands in in Lao PDR, Cambodia, Thailand and coral reefs, mudflats, mangroves, and seagrass beds along the coastal Viet Nam Delta.

An estimated 2,843 wetland-dependent species thrive in the inland wetlands of Mekong, many endemic to the region. With climate change and urban development threats, many species face the elevated risk of extinction. Almost half of the region's waterbird populations are experiencing a decline.

Urban sprawl continues to fill in and convert inland wetlands for infrastructure development, further compressing floodplains. In contrast, the area of human-made wetlands (such as rice paddies, ponds for aquaculture, and reservoirs) has expanded significantly over time.

Saving the Mekong wetlands

Wetland ecosystem services such as human health, well-being, and security are estimated to be worth US$ 47.4 trillion¹. The Mekong Region’s rich wetland ecosystem provides benefits to nearly a quarter billion people across five countries. These wetlands sustain livelihoods, and many generations have relied on their ecosystem services, which include, but are not limited to fisheries, climate regulation, food, and water.

Hydropower dams, unsustainable fishing, and extensive pollution are the major drivers of change for the wetlands of Mekong. Based on the recently published Indo-Burma Wetlands Outlook (2022)⁴, most indicators of wetland biodiversity and ecosystem services show a negative trend. On the contrary, non-heterogeneous environments such as paddy fields, aquaculture ponds, and hydropower dams have increased dramatically and are associated with negative tradeoffs that ultimately impede the other indicators.

The need is to scale up efforts to conserve the remaining wetland ecosystems while restoring floodplain connectivity wherever possible. To slow down or halt the degradation of wetlands, the following aspects are critical for Mekong countries to focus on and build upon:

1. Setting up action on wetlands conservation, management and restoration backed by science and supported by local people with effective wetland governance mechanisms and special focus on integrated wetlands management.
2. Promoting the agenda of wise use of wetland ecosystems, which supports local communities dependent on wetland ecosystems while preserving the overall health and functionality of these ecosystems in accordance with the Ramsar Convention
3. Increasing the budget for wetland conservation and restoration at all levels within climate finance policies to sustain green growth.
4. Satellite-based wetland inventory and monitoring can support better decision making in the Mekong countries and support identification regional conservation and restoration of wetlands.
5. Bridging the divide between science and people, to enhance the use of wetland system as component of large scale, nature-based solutions.

Researchers at SEI Asia  through its Water Beyond Boundaries Initiative (WBBI) are currently collaborating with Thailand's Department of Water Resources, Ministry of Natural Resources and Environment, and Nakhon Phanom Provincial Office of  Natural Resources and Environment to develop and enhance the knowledge base to promote resilient communities and wetland ecosystems in the Lower Songkhram Basin (a Ramsar site). Through co-developing tools using remote sensing and modelling techniques, efforts are continuing to monitor and assess wetland health and potential impacts of water resources development, land use and climatic changes to support better informed decisionmaking at provincial and national scales.

References

1. Davidson, N. C., van Dam, A. A., Finlayson, C. M. & McInnes, R. J. Worth of wetlands: Revised global monetary values of coastal and inland wetland ecosystem services. Mar Freshw Res 70, 1189–1194 (2019).

2. Thorslund, J. et al. Wetlands as large-scale nature-based solutions: Status and challenges for research, engineering and management. Ecol Eng 108, 489–497 (2017).

3. Mitsch, W. J. & Gossilink, J. G. The value of wetlands: importance of scale and landscape setting. Ecological Economics 35, 25–33 (2000).

4. IBRRI. Indo-Burma Wetland Outlook. (2022).

5. Li, D., Long, D., Zhao, J., Lu, H. & Hong, Y. Observed changes in flow regimes in the Mekong River basin. J Hydrol (Amst) 551, 217–232 (2017).

6. Intralawan, A., Wood, D., Frankel, R., Costanza, R. & Kubiszewski, I. Tradeoff analysis between electricity generation and ecosystem services in the Lower Mekong Basin. Ecosyst Serv 30, 27–35 (2018).