World Aquaculture Magazine - June 2020

WWW.WA S.ORG • WORLD AQUACULTURE • JUNE 2020 19 were conducted on the perceptions of farmers using different aquaculture systems in the Mekong Delta about the impacts of climate change and saltwater intrusion, as well as methods of adaptation and suggestions, give a very informative picture about the need for further and urgent actions (Anh 2014, Mai 2016). Aquaculture and fisheries are a top priority for development in the Mekong Delta. Promoting coastal aquaculture with various species, different farming systems in specific areas are of dynamic and significant solutions to adapt to climate change and saltwater intrusion in the region. More supportive activities for further development of the industry are needed. In the last decade, many national strategies, plans, actions, decisions, resolutions on climate change and saltwater intrusion were issued and carried out. The Vietnam Government Resolution No. 120 NQ-CP (dated 17 Jan 2017) put aquaculture and fisheries as the top priorities for agri-aquaculture production structure for sustainable development of the Mekong Delta under climate change. Shrimp Culture Shrimp culture is one of the most important socioeconomic sectors in Vietnam. The history and development of the shrimp industry is well documented (Quynh 1992, Hai 2015). Currently, shrimp aquaculture is conducted in 736,000 ha, from which 762,000 t are produced, of which 632,000 ha and 298,000 t are for tiger shrimp and 104,000 ha and 464,000 t are for whiteleg shrimp. The Mekong Delta has 90 percent of the total shrimp culture area and 70 Introduction World aquaculture has reached total production of more than 82 million tons, and Vietnam stands as the fourth largest aquaculture producer in the world with a total production of 4.124 million tons (FAO 2020). Aquaculture is increasingly diverse and innovative, with different species, water environments, culture systems, and levels of intensification to meet typical needs and conditions. However, aquaculture is now also challenged by environmen- tal pollution, diseases, markets and especially climate change and saltwater intrusion. The concerns of climate change, saltwater intrusion and its impacts as well as solutions for adaptation in aquaculture around the world have been studied and are well document- ed (Cochrane et al. 2009, Shel- ton 2014, Barange et al. 2018). In Vietnam, especially in the Mekong Delta, with 70 percent of the aquaculture area of the country, climate change and saltwater intrusion are major concerns (ADB 2013, MONRE 2019). Vietnam, especially the Mekong Delta is one of the most vulnerable places in the world. Scenarios of climate change and sea level rise indicate that, by the end of 21st century, temperate in Vietnam will increase by 1.6-3.5 C, rainfall will increase by 2-10 percent and sea level will rise by 49-95 cm, depending on scenario. If sea level rises by 1 m, 39 percent of the natural area of the Mekong Delta will be inundated (MONRE 2012). In recent years, the Mekong Delta has been challenged by saltwater intrusion. During the dry season, especially in 2016 and 2020, brackish water initially affected inland areas of up to 55-100 km from the coastline, causing issues in production and socioeconomics (SIWRR 2016, SIWRR 2020). Several surveys Promoting Coastal Aquaculture for Adaptation to Climate Change and Saltwater Intrusion in the Mekong Delta, Vietnam Tran Ngoc Hai, Nguyen Thanh Phuong, Nguyen Van Hoa, Le Quoc Viet, Ly Van Khanh, Chau Tai Tao, Nguyen Thi Ngoc Anh, Ngo Thi Thu Thao and Patrick Sorgeloos ( C O N T I N U E D O N P A G E 2 0 ) World aquaculture has reached total production of more than 82 million tons, and Vietnam stands as the fourth largest aquaculture producer in the world with a total production of 4.124 million tons. Aquaculture is increasingly diverse and innovative, with different species, water environments, culture systems, and levels of intensification to meet typical needs and conditions. FIGURE 1. Rotational rice-shrimp farming system with shrimp culture in the dry season.