Project “Improving the stability of shrimp-rice farming system in the Mekong Delta” has been implemented in Thi Tuong, Hoa My, Cai Nuoc, Ca Mau province and showed positive effects on extensive, commercial shrimp farming and rice growing. This sustainable farming system may be the answer to climate change.
Commercial shrimp farmer Ngo Van Su is among the most successful farmer when following the project which starting work with six crops, only two failure ones. With four crops, he earns a high profit of VND 70 million per crop. According to Su, rice creates green and clean water environment and finally boosts shrimp production.
The project has been started since 2013 with farms that meet these such requirements: must have fresh water reservoir, pond banks should be reinforced without leaks. Firstly, a total of 12 shrimp farms were divided into two experimental groups with six trial farms and six control farms. During experimental period, significant differences were observed in productivity between two groups. Six trial farms has higher productivities than the others. Ngo Van Su explained that because of a proper washing salt process, rice grows well again in shrimp ponds.
Through research on soil nutrition, salinity and pH, the scientists have found solutions to fertilization and salt washing. The initial paddy rice fertilization during dry season has produced a successful rice crop whilst shrimp ponds surrounding. Six trial farms following these practices earn a higher profit than themselves previously.
Currently, there are 18 farms adopt green water technique, earning a high profit of VND 150 – 200 millions per ha. One project member, Nguyen Cong Thanh at Minh Hải Seafood Institute said that, the use of green water technology in semi-extensive and extensive shrimp farming with low density was proven to be the most functional.
>>Thanks to clean shrimp farming environment with water from paddy rice and low stocking density of 15 PL / m2 (tiger shrimp) and 20 – 30 PL/15 m2 (white-leg shrimp) , shrimp grow rapidly and suffer less from diseases. Two stocking density of 8 PL / m2 shrimp ponds can produce shrimp of 40-50 size after 120 day growth, Ngo Van Su earns some millions VND.