At the Southern end of Vietnam lies the Mekong Delta. It’s Vietnamese name, Cuu Long means “Nine Dragons,” referring to the nine rivers that come from six countries, and meet there, ending a journey of several thousand kilometres to the sea. The Mekong Delta is the most fertile area in Vietnam, and also the most fragile. It is the country’s rice bowl, and it is now slowly sinking into the sea. Kannicker Petchkaew
The Mekong Delta is one of Earth’s most fertile areas for agriculture. The land is carpeted with lush green vegetation with rice paddies and fruit trees that feed a third of the nation and in addition, provides 60 percent of its shrimp and fish. Like all river deltas, the Mekong brings minerals from upstream and deposits them across the delta. The river delta provides tons of all the minerals and elements that a food crop needs to grow, it can grow more plants per acre than regular soil, which is limited in nutrients.
The Mekong Delta is the only place in the entire river basin where rice can be grown and harvested 7 times a year. But climate change and other human activity has begun to turn this oasis into a waste land. The delta is rapidly urbanizing and that is requiring more extraction of groundwater to provide for the needs of a burgeoning population. The water extraction projects have caused many local waterways to sink and dry up providing seawater an entry way into the delta poisoning the rich soil. Meanwhile, erosion and drought is affecting productivity while leaving homes and infrastructure to collapse.
Alex Chapman and Van Pham Dang Tri of The Conversation note that a 2015-2016 drought (the worst drought in a century) caused salt water to intrude 50 miles inland and destroyed at least 160,000ha of crops. The rice paddies are the first to go with hardy tropical fruits, including saltwater tolerant coconut close behind. The drought has caused shrimp and fish ponds to dry up. These changes in combination have caused a migration of 1.7 million people out of the delta in the past 10 years.
One relatively low profile article by Vietnamese academics may be a vital piece of the puzzle. The study, by Oanh Le Thi Kim and Truong Le Minh of Van Lang University, suggests that climate change is the dominant factor in the decisions of 14.5% of migrants leaving the Mekong Delta. If this figure is correct, climate change is forcing 24,000 people to leave the region every year. And it’s worth pointing out the largest factor in individual decisions to leave the Delta was found to be the desire to escape poverty. As climate change has a growing and complex relationship with poverty, 14.5% may even be an underestimate.
There are a host of climate-linked drivers behind migration in the Delta. Some homes have quite literally fallen into the sea as the coast has eroded in the Southwestern portion of the delta – in some places 100m of coastal belt has been lost in a year. Hundreds of thousands of households are affected by the intrusion of salt water as the sea rises and only some are able to switch their livelihoods to salt-water tolerant commodities. Others have been affected by the increased incidence of drought, a trend which can be attributed in part to climate change, but also to upstream dam construction.
Governments and communities in developing countries around the world have already begun taking action to manage climate change impacts through adaptation. Our recent research in Vietnam flags a warning about how this is being done. We show that a further group of people are being forced to migrate from the Mekong due to decisions originally taken to protect them from the climate. Thousands of kilometres of dykes, many over four metres high, now criss-cross the delta. They were built principally to protect people and crops from flooding, but those same dykes have fundamentally altered the ecosystem. The poor and the landless can no longer find fish to eat and sell, and the dykes prevent free nutrients being carried onto paddies by the flood.
All this demonstrates that climate change threatens to exacerbate the existing trends of economic migration. One large scale study of migration in deltas has found that climate factors such as extreme floods, cyclones, erosion and land degradation play a role in making natural resource-based livelihoods more tenuous, further encouraging inhabitants to migrate.