HCM CITY — As profits rise from shrimp-rice rotation models, Kiên Giang Province’s Vĩnh Thuận District plans to expand the cultivation area to a total of 10,000ha.

Under the highly profitable model, farmers use the same field to grow blue-legged prawns and white-legged shrimp in the dry season, while rice is cultivated in the rainy season.

Phạm Văn Hậu, vice chairman of the Vĩnh Thuận District People’s Committee, said that breeding prawns lasts for six months and shrimp three months.

With such a schedule, farmers can harvest three crustacean crops and one rice crop a year.

The model provides an average profit of about VNĐ300 million (US$13,200) per ha per year, he said.

The district plans to expand the model in Vĩnh Bình Nam, Vĩnh Bình Bắc and Bình Minh communes, which are located along the Cái Lớn River, and in Tân Thuận Commune.

The shrimp bred under this model is considered “clean” because farmers do not use chemicals. In addition, the quality of the field soil improves and provides natural food for the shrimp.

Also, farmers no longer have to worry about selling their products as traders come to their fields to buy the shrimp.

Võ Văn Sữa, who has 3ha of land in Vĩnh Bình Bắc Commune, said he earns a profit of more than VNĐ900 million ($36,600) a year from shrimp and rice. In the past, his family bred black tiger shrimp and did not always earn a profit.

To enhance efficiency, the district will expand the market for blue-legged prawns as farmers are more willing to switch to the model when there is a stable outlet.

“Under the district’s agricultural restructuring plan, the district is developing the rotation model, but many farms are still breeding only shrimp,” he said. This could lead to polluted water resources and soil degradation, which could damage farms.

This year, the district will register a collective brand for its blue-legged prawn and rice planted under the shrimp-rice rotating model, he said.

Shrimp and rice are two key agricultural products in the Cửu Long (Mekong) Delta district of Vĩnh Thuận, where the soil is affected by aluminum and saltwater intrusion.

The district’s blue-legged prawns are sold domestically and also exported to Cambodia. 

Last year, the district bred about 23,880ha of various kinds of shrimp with a total yield of about 12,580 tonnes, up 20 per cent against 2016.

Of the figure, blue-legged prawn accounted for 5,551 tonnes, and white-legged shrimp and black tiger shrimp the rest. — VNS