Ecosystems in the Greater Mekong: past trends, current status, possible futures

Posted on May, 02 2013

The Greater Mekong Subregion (GMS: Myanmar, Thailand, Cambodia, Laos, Vietnam, and Yunnan and Guangxi in China) is undergoing unprecedented changes. Many of these are positive, reflecting political stabilization and economic growth following decades of poverty and conflict. But the rate and type of development is also threatening critical natural resources, particularly native forests, the Mekong River and its tributaries, and many wild plant and animal species. The GMS faces a critical choice: it can either continue with unsustainable development and see many of its unique natural resources disappear forever or switch policies and choose a more sustainable path into the future. This report gives an overview of what is happening, and provides key recommendations for how natural resource management can be made more sustainable.

The core of the report is a series of maps, developed by WWF, describing the historical trends, current status and future projections of forests in the GMS excluding China. Future projections for the period 2009 to 2030 contrast two scenarios; an unsustainable growth scenario, which assumes deforestation rates between 2002 and 2009 continue, and a green economy scenario, which assumes a 50 per cent reduction in the annual deforestation rate relative to the unsustainable growth scenario, and no further losses in key biodiversity areas.

Recent changes: between 1973 and 2009, the GMS (excluding China) lost just under a third of its forest cover (22 per cent in Cambodia, 24 per cent in Laos and Myanmar, and 43 per cent in Thailand and Vietnam) according to WWF’s analysis. In official statistics for tree cover across the whole of the GMS, these losses are partially masked by large-scale plantation establishment in Vietnam and China, where there has been a gradual replacement of natural forests by monoculture plantations. Myanmar accounted for over 30 per cent of total forest loss in the GMS over this period. At the same time, forests became far more fragmented: large areas of intact forest (core areas) declined from over 70 per cent of the total in 1973 to only about 20 per cent in 2009.

Projections: by 2030, under the unsustainable growth scenario, another 34 per cent of GMS forests outside China would be lost and increasingly fragmented, with only 14 per cent of remaining forest consisting of core areas capable of sustaining viable populations of wildlife requiring contiguous forest habitat. Conversely, under the green economy scenario, core forest patches extant in 2009 would remain intact, although 17 per cent of GMS forests would still be converted to other uses. Regardless of scenario, deforestation “hotspots” include the margins of large forest blocks remaining in Cambodia, Laos and Myanmar. The model suggests that deforestation in Vietnam will be distributed in small pockets across the country, although the greatest losses are anticipated in parts of the Central Highlands and northern provinces. This report also contains a map, constructed from historical patterns, of likelihood of conversion of any particular forest block, based on the distances from roads, non-forest areas, water, cities, and new and planned mines, along with elevation and slope.

The Mekong river basin contains one of the most productive and diverse river systems on Earth. Its connectivity and natural variability of flows support exceptional productivity, while sediments and nutrients sustain the landforms, agriculture, and marine fisheries of the Mekong Delta. The Mekong river system supports the world’s largest known fish migration. Thirteen unique, yet connected, ecosystems exist. Despite long-term intensive human use, the freshwater system has maintained connectivity between 11 of the 13 ecosystems in about 60 per cent of the system by area. The growing need for energy in the GMS has led to an unprecedented rate of dam building, impacting on freshwater ecosystems, the river’s connectivity and flow, and the people that rely on these. Eleven dams are planned on the Mekong main stem. Main stem dams:
● Cause ecosystem collapse and biodiversity loss;
● Hinder movements of fish up and down the river system to grow or spawn;
● Harm wild fisheries in Laos, Thailand and Cambodia;
● Reduce sediments and nutrients that build and feed the delta’s productivity;
● Degrade the functionality of the whole interconnected ecosystem.

Other major river systems in the region face similar challenges, but there are opportunities to benefit from lessons learned from experience in the Mekong basin.

Wild species
The report maps the enormous decline in range of several important and iconic species of the region: the tiger, elephant, Irrawaddy dolphin and endemic saola, along with the historical range of the Javan rhino, now extinct in mainland SE Asia since April 2010. All the species described face the same fate as the rhino unless conservation becomes more effective.

Drivers of change
WWF identifies four key drivers of change of the region’s ecosystems:
1. Human population growth and increasing population density, along with worsening income inequality;
2. Unsustainable levels of resource use throughout the region, increasingly driven by the demands of export-led growth rather than subsistence use;
3. Unplanned and frequently unsustainable forms of infrastructure development (dams, roads and others);
4. Government policies, along with lack of integrated planning, poor governance, corruption and wildlife crime on a massive scale.

The report outlines ten recommendations, which WWF believes will enable GMS countries to achieve their aspirations of building greener economies:

1. Halt impacts to ecological patterns and processes that are at their breaking point. Key actions in this regard include:
• Preventing further conversion of primary forest in the GMS;
• Preventing the construction of dams on the main stems of major rivers, and supporting only sustainable hydropower projects on select tributaries;
• Implementing species-specific conservation and recovery actions for endemic species; and
• Ceasing the illegal wildlife trade.
2. Significantly increase the level of integration, the spatial scale, and the timeframe of planning.
3. Commit sufficient and sustainable financing for conservation.
4. Incorporate the values of ecosystems and the services they provide into decision-making.
5. Insist on greater responsibility of companies operating in or purchasing from the GMS.
6. Improve regional and international consultation and cooperation.
7. Empower communities and civil society to more significantly and effectively participate in decision-making.
8. Enforce existing laws, policies, and regulations.
9. Ensure effective and representative protection of the region’s natural heritage.
10. Restore natural capital in strategic areas.

Report cover - Ecosystems in the Greater Mekong: past trends, current status, possible futures
© WWF-Greater Mekong