Climate Change's Impacts on Vietnam Aquaculture Sector

From AquacultureHub - Posted by Ha Thu on December 22, 2011 at 10:00am


            Vietnam mangrove forest before 2000 (left) and now (right)

According to a report by the World Bank (2009), Vietnam is one of the five countries predicted to be among the most affected by climate change due to its long coastlines, the high concentration of population and economic activity in coastal areas, and a heavy reliance on fishery and aquaculture sectors, which accounted for 6.6 percent of GDP in 2008. Climate change has been growing in both of its intensity and frequency, causing a rise in seawater level, aquaculture farms, the mangrove area, - home to more than 5 millions of habitats and thousands of species of fresh and saline water creatures. The consequential fluctuations of earth temperature are expected to cause death for both natural and kept aquatic animals. Its appearance in the form of floods and severe typhoons is causing heavy lost in both human lives and infrastructure constructions, aquaculture farms, fishing boats/equipments.

A closer look on this issue would somehow bring us a clearer picture of the impacts of Climate change, which is more and more affecting to us all, to our next generations. This look, however, is not a core of the blog, but the call for the awareness of the whole world takes this part, because the picture is far larger than this (not only Vietnam, but the whole world have been under this phenomenon; not only aquaculture but agriculture, and food security are also in vulnerable condition). Should us, each individuals and organizations, once recognize the issue, don't just give “a nod”, but a share of responsibility to save the best for last, because whence we are global inhabitants, the responsibility portions are equally shared among us?

1) The importance of fishery to Vietnam economy

 Vietnam’s fishery and aquaculture sectors’ production accounted for 6.6% of the national GDP (2008), subsistence to 58% of coastal population, in which 700 fishermen and 10,000 workers in processing factories and 2,140 service suppliers.

  • Viet Nam has a coastline of 3,260 km that crosses 13 latitudes, from 8°23'N to 21°39'N
  • The continental shelf has a surface area of some 700,000 km-, with an Exclusive Economic Zone (EEZ) of more than 1 million km2
  • Vietnam has over 4,000 islands and the coast has more than 400,000 hectares of mangrove stands
  • There are four main fishing areas: Gulf of Tonkin, shared with China; Central Vietnam (the Southern Mainland Shelf); Southeastern Vietnam (Northern Sunda Shelf and part of the Central Sunda Shelf); and Southwestern Vietnam (part of Gulf of Thailand), shared with Cambodia and Thailand.

EXPORTS IN 2003 - Main Products

[Source: VASEP ]

  • Total fisheries production in 2003 reached 2,536,361 MT, of which the marine catch was 1,426,223 MT and aquaculture and inland catches totaled 1,110,138 MT
  • It is estimated that only half of the area suitable for aquaculture in Vietnam is being used at present, and approximately 800,000 ha can be developed for use by this sector
  • Vietnam has 332 seafood processing plants, of which 70 percent are located in the southern region; 24 percent in the central region and 6 percent in the north
  • 100 plants have qualified for exporting to the European Union, more than 200 are applying HACCP * Ho Chi Minh City has about 50 seafood companies
  • Many state-owned enterprises are converted into joint stock companies, or in other ways changed their ownership structure
  • Exports of sea products in 2003 were US$ 2.240 billion, a 10.74 percent increase over 2002

2) The impacts of climate change on Vietnam agriculture and its severe results                     

A. Climate change causes rises in temperature, sea level, and rainfalls

a) Sea level rises: There are number of studies predicted sea level raise and its impact in Vietnam. For instance, the sea level increased 10 – 20cm in the last 50 years based on the reports of Vietnam Ministry of Natural Resources and Environment (MONRE 2008). Some models predict sea level would increase by about 5cm per decade, in a total of about 69cm in 2070 and up to 100cm relative to 2100(Thanh et al.,2004). "Sea levels are expected to rise 1m by the end of this century which will flood up to 12 per cent of Viet Nam," said Dr Hoang Nghia Son, director of the Institute of Tropical Biology. One study estimates that a 100cm rise in sea level by 2100 would affect approximately 9.3 percent of Vietnam’s land area and 10 percent of the population (Dasgupta et al.,2007). Other studies project faster sea level rises and, consequently, that larger parts of the country are submerged (Bahuet, 2008). Also associated with sea level rise is saltwater intrusion. In 2004, saltwater introduced into 30-50km in the Red river and 60-70km in the Mekong river (Thank et al,.2004), resulting in more than 1.7 million ha of impacted land.

b) Temperature changes: Currently, global average temperature is higher 0.74oC compared to it in the year of 1850 and is estimated to increase 1.4 - 6.4oC in 2100, and estimated as the highest temperature recorded over the past 10,000 years.

c) Rainfall rises: Climate change will increase annual total rainfall everywhere in Viet Nam. According to the A2 high emissions scenario, average rainfall is estimated to increase by an average of 6.6 percent during the 21st century, and will increase by as much as ten percent in the Red River Delta area, especially in the wetter months (June to November). The probability of extreme rainfall events and flooding will also increase, especially in northern regions including cities such as Hanoi (which suffered from unusual and extreme rainfall in November 2008), and increased risks of landslides in mountainous areas. In contrast, during the dry months (December to May), average rainfall will decrease by about 20 percent, especially affecting the southern regions including the Mekong Delta. Decreasing rainfall in dry months will lead to increased drought risks, which is also because of higher temperatures that increase evapotranspiration.


Impacts to the natural environment:

  • Coastal wetlands will be heavily affected, especially in HCM City and the Cuu Long (Mekong) Delta provinces of Tra Vinh, Soc Trang, Bac Lieu and Ca Mau, home to many important wetland areas plus eight national parks and 11 nature reserves will be flooded, killing many species of flora and fauna (Dr Hoang Nghia Son, director of Vietnam Institute of Tropical Biology). "In addition, rising sea levels will mess with the ecosystem and threaten flora through salination, erosion and high tides. Said Dr Le Anh Tuan of Can Tho University's Natural Resources and Environment Department.
  • Rises in temperature and rainfall will cause death to salt water bottom – layer creatures – which are feeds to some kept important aquatic animals in semi-intensive and intensive methods that base almost on natural conditions.

  • Rises in temperature and rainfall are also expected to play and important role in the spread of harmful species including apple snails and mimosa pigra.
  • To saline and brackish water shrimp aquaculture, the most important factor of breeding environment that affects the growth of shrimp is the salinity, which will decrease when rainfall rises, once reaches beyond shrimp’s resistance will cause stress and shock to death or Slow Growth Syndrome” Mr. Giang, a shrimp farmer said. In the first eight months of 2011, Ca Mau (southern province of Vietnam) has encountered death cases of 25—40 percent of total cultivated area, equivalent to 12.300ha of shrimp farms, most of which are using improved extensive method. The same situation has also found in some coastal districts such as Cau Ngang, Duyen Hai, Tracu, Chau Thanh with the damage of 23 percent over 1.74 billion of breeding shrimp in 23,000ha of shrimp farms.

Pic 2 - Shrimp death in a Tien Giang shrimp ponds

  • Viet Nam has 5,000 km of river dykes and 3,000 km of sea dykes that need expansion and reinforcement. Much of Viet Nam’s 3,200 km coastline is or should be protected by mangrove forest, which mitigates against the impact of typhoons and storm surges. For example, it was estimated that in Kien Thuy District, a four-meter high storm surge resulting from storm number 7 in 2005 (typhoon Damrey) was reduced to a 0.5 m wave by restored mangrove forests16. (UN facts)


Vietnam Mangrove ecosystem - home to more than 5 millions of habitats and thousands of species of fresh and saline water creatures provides both goods and services for coastal community, helps to improve livelihood options and protect them from natural disaster by providing variety of environmental support. Mangroves play an important role for maintaining the coastal ecosystem and provide a variety of environmental supports. It serves as a protection for a myriad of juvenile aquatic species, functioning as a habitat for a variety of terrestrial fauna and a source of nutrients that helps to sustain many complex food chains.

  • Fishing communities along the Mekong River produce over 1 million tons of basa fish annually and livelihoods and fish production will suffer from saltwater intrusion resulting from rising sea level and dams.

Impact on human lives:

  • Sea level rise are estimated to cause homeless to more than....
  • The Climate Change Vulnerability Index (CCVI) evaluates 42 social, economic and environmental factors to assess national vulnerabilities across three core areas, including (1) exposure to climate-related natural disasters and sea-level rise; (2) human sensitivity, in terms of population patterns, development, natural resources, agricultural dependency and conflicts; and (3) future vulnerability considering the adaptive capacity of a country’s government and infrastructure to address climate change effects. The countries most at risk are characterized by high levels of poverty, dense populations, exposure to climate-related events; and their reliance on flood and drought prone agricultural land1. [source: UN facts].
  • Climate change keeps the coastal community in risk and destroys property. Facilities of sanitation, home and drinking water are damaged. Food crisis arise and disease out break.
  • Fishers, fish farmers and coastal inhabitants will bear the full force of these impacts through less stable livelihoods, changes in the availability and quality of fish for food, and rising risks to their health, safety and homes. Many fisheries-dependent communities already live a precarious and vulnerable existence because of poverty, lack of social services and essential infrastructure.
  • Social stresses. Changes, particularly reductions, in income and employment may contribute to a wide variety of family and community stresses. 
  • Political conflict. Changing relative harvest levels can upset the political balance in agreements over allocation of mixed-stock fisheries and transregional or transnational fisheries. Changes in costs and opportunities due to changes in weather and ice conditions.
  • With increased rainfall in June to November in Viet Nam as well as other riparian countries of the Mekong and Red rivers, there is a strongly increased risk of river flooding. River floods are already being exacerbated by deforestation in the upstream reaches of these rivers. Examples include the devastating river floods that hit the Mekong Delta in 2000 and 2001 – some of the worst in living memory. In 2000 and 2001, respectively 481 and 393 people perished – the majority being children. About 900,000 houses were damaged in 2000 and 350,000 in 2001. Increased damming and diversion of water from the Mekong and Red rivers for hydroelectricity, agriculture, industry and household use may reduce the risks of peak floods in the wet season, but the net effects of existing and future dams and climate change is not yet clear. Water diversion in upstream parts of the river basins is increasing and, notably, many dams are being planned in the mainstream of the Mekong river (in China, Laos, Cambodia), which is highly likely to reduce the dry season water flow and negatively affect water supply and agriculture downstream.

Impacts on fishery in general (economy and infrastructure in fishery sector):

  • Those logistic infrastructure constructions such as fishery ports, anchorages

    • Climate change causes vulnerability of the aquaculture value chain (Losses in fishery harvest cause scarcity in breeding resources for farmers and raw materials for processing factories) – leading to reduction in aquaculture business productivity.
    • Economically, climate change and its effect could include changes in prices. Fisheries markets are highly sensitive to supply. Changes in harvests tend to have opposite effects on prices. Changes in fishing and processing income and profits. Changes in harvest volumes, prices and costs combine to affect income and profits earned in both fish harvesting and fish processing. Changes in local and statewide tax revenues. Fisheries business taxes, aquaculture enhancement taxes, and fisheries marketing assessments are directly tied to the ex-vessel value of harvests.
    • Because changes in climate are likely to increase harvests of some species while reducing harvests of other species, it is unlikely that the relative magnitude of the change in total exvessel or wholesale value, as well as other economic effects, would be as great as the relative magnitude of the change in value for individual species.
    • Changes in the physical environment, such as weather and ice conditions, may affect where and when fishing is physically possible as well as the costs of fishing. In the short term, to the extent that changes in harvests are not offset by changes in prices, the value of current harvest.
    • Without major action such as dyke reinforcements and improved drainage, a one-meter rise in mean sea levels along the coast of Viet Nam would cause an estimated threat of inundation to 17,423 km2 or 5.3% of Viet Nam’s total land area. Of that total, nearly 82% is in the Mekong Delta, 9% in the Red River Delta and over 4% each in the North Central Coast and South East regions. The latter includes Ho Chi Minh City and includes land along the Saigon/Nha Be river.
    • For example, transportation infrastructure is often damaged or destroyed by storms and floods. During the period of 2001-2005, extreme weather events cost the transportation sector VND 2,571 billion in damage19. If mean sea level rises by one metre, 11,000 km of roads could be submerged. The total length of national highways threatened by inundation in the country will be 695 km and in the Mekong Delta alone 495 km, without measures taken. [Source: UN facts].

B. Climate change increase the severity of natural disasters such as storms and whirlwinds, typhoons

  • Viet Nam has 5,000 km of river dykes and 3,000 km of sea dykes that need expansion and reinforcement. Much of Viet Nam’s 3,200 km coastline is or should be protected by mangrove forest, which mitigates against the impact of typhoons and storm surges. For example, it was estimated that in Kien Thuy District, a four-meter high storm surge resulting from storm number 7 in 2005 (typhoon Damrey) was reduced to a 0.5 m wave by restored mangrove forests. [Source: UN facts].
  • Storms and whirlwinds will devastate coastal zones, destroying forests, degrading water quality and killing unestimated aquatic species.
  • Viet Nam experiences an average of 6-8 typhoons annually14. During El Niño years typhoons appear to be more frequent, stronger, and with landfall over a wider area. Past observations do not bear out a structural change in the typhoon pattern or in intensity in the Western Pacific / Southeast Asia as a result of climate change, but intensification of hurricanes (=typhoons) has been observed in the Southern Atlantic / Caribbean region. Nevertheless, the possibility of gradual intensification of tropical storms and typhoons exists, according to an update of the IPCC’s fourth assessment of 200715, also in Southeast Asia. Furthermore, damage potential from tropical storms and typhoons appears to increase as a result of increasing population density in exposed areas and higher value economic infrastructure in these areas. [Source: UN facts].
  • Changes in fishery seasons emerging from climate change cause heavy economy losses to fishermen - those who base mostly on this subsistence. Consequently, fishermen have to change their traditional means of living; the fishery picture has lost a major raft.

Pic 3 - Fishermen in Duc Trach province dismount their fishing boat to change their means of living

3. Breakthrough at Durban Climate Change Conference (Source:

The Minister for Climate Change and Energy Efficiency Greg Combet has welcomed the outcome of the Durban climate change conference which has made a significant breakthrough in tackling global warming.

The historic Durban agreement opens the way to bring all of the world's major greenhouse gas emitters - including the United States and important developing economies like China, India and Brazil - into a new international legal framework for reducing carbon pollution.

In addition, the 194 countries represented at the United Nations conference adopted a package of measures which will consolidate and build on the extensive actions already under way around the world to reduce emissions.

These Durban outcomes are good news for the environment.

They set the world on a path of long-term action to tackle climate change through a regime with wide global coverage and strong environmental effectiveness.

They will complement Australia's carbon price mechanism by boosting confidence in global mitigation efforts, providing a sound basis for investment in clean energy and stimulating growth in carbon markets.

The Australian Government went to Durban with three key objectives: building on emissions reduction pledges made at last year's UN conference in Cancun; taking the next steps towards a legal framework to cover all major emitters; and promoting market mechanisms to cut emissions in the lowest cost.

Durban has delivered on each of these objectives.

Firstly, it has built on the decisions made in Cancun where 90 countries representing 80 percent of global emissions made pledges to reduce carbon pollution by 2020 as part of a goal of keeping average temperature increases to 2 degrees Celsius above pre-industrial levels.

In Durban, countries ensured further progress on this agenda by agreeing to:

    * Improved transparency and better monitoring, reporting and verification of countries' emissions reduction actions;

    * Governance arrangements, which will establish a new Green Climate Fund to help developing countries reduce emissions and adapt to climate change;

    * Progress the REDD+ mechanism which will reward developing countries for reducing emissions from deforestation and forest degradation;

    * Develop new market mechanisms to drive opportunities for low cost greenhouse gas abatement;

    * An Adaptation Committee to help developing countries adapt to the impacts of climate change;

    * Rules for a new Technology mechanism to speed up transfer of low pollution technologies to developing countries.

These initiatives will add momentum to the extensive climate change action already under way around the world and provide a strong foundation for reducing emissions through to 2020. The transparency measures are especially welcome because they will ensure countries deliver on their emissions reduction pledges.

The second achievement at Durban was the adoption of a mandate for parties to the UN Framework Convention on Climate Change to negotiate a new legal agreement by 2015. The new agreement would take effect from 2020.

A central element of this mandate is that the new agreement will establish for the first time a common legal framework applying to both developed and developing countries.

This is an important first step towards a comprehensive agreement covering all major economies.

If the agreement is concluded it will see developing countries take on obligations, allowing the world to move on from the Kyoto Protocol's unsustainable divide between developed and developing countries and ensuring all nations do their fair share to cut global emissions.

4. Conclusion

Climate change is a global environmental challenge which can only be solved with global action. With such severe impacts that Vietnam and especially its aquaculture sector has been through, and with the results of the recent Durban Climate change Conference, a question which has been raised, that “If Vietnam and especially other developing countries, if we and our next generations can believe in a brighter future for this world?" still be left unanswered. But it leaves the goal for analysts continues to be laying out and assimilating information that improved management of fisheries and of marine ecosystems can undoubtedly play an important role in adapting to the impacts of climate change, it leaves the goals for us to feel the responsibilities among us are now called to share.

howdy folks