The rice-shrimp cultivation system in the Mekong Delta has proven to be sustainable and adaptable to climate change, bringing farmers greater economic efficiency than monoculture production. However, unless this farming system is maintained in a scientific and rigorous manner, it risks collapsing.
The risk of a collapse of the shrimp-rice cultivation system
On July 2, Kien Giang Agricultural Extension Center, in cooperation with Binh Dien Fertilizer Joint Stock Company and Ho Quang Tri Company – Ong Cua Rice Brand, coordinated the organization of a seminar “Improving the Value of Rice – Shrimp” to provide solutions to increase of productivity and quality of ST rice varieties grown on shrimp farms in Kien Giang. The workshop took place in An Bien and An Minh (Kien Giang) districts with the participation of local authorities, agricultural cooperatives, rice shrimp farmers and companies in the price chain. Treatment of rice shrimp.
Delegates attending the workshop visited the agricultural material stalls. Picture: Trung Chanh.
dr Le Van Dung, deputy director of Kien Giang Agricultural Extension Center, said that Kien Giang province has the peculiarity of being hit by both flooding and salt water intrusion from the sea in the flood season from the Mekong River. In the past, when the province mainly produced monocultures of rice or rice-freshwater fish, saltwater intrusion was always a major challenge for production. However, from the year 2000, in the transition to the rice-shrimp model, salt water is the advantage for the development of brackish water aquaculture, the crop rotation in paddy fields, resulting in higher economic value for farmers.
According to Mr. Dung, Kien Giang province had about 60,000 hectares of rice shrimp production in 2010, but now it has grown to 102,400 hectares, accounting for almost 50% of the acreage under this model in other provinces. Coastal provinces in the Mekong Delta.
After more than 20 developments, farmers have found many creative ways to transform the rice shrimp model from a tree to an animal (growing rice and raising black tiger shrimp) to a multi-tree, multi-child model. The rice and shrimp model has now become a rice and shrimp cultivation system. In addition to rice, farmers in areas of high salinity grow saltwater grass (mainly reed grass) to substitute and extract raw materials for making handicrafts. About the shrimp: From the beginning, only black tiger shrimp were farmed, now there are also white leg shrimp, giant freshwater shrimp, sea crab, cockle…
Thanks to the shrimp rice model, high-quality rice has been produced that meets strict standards, especially organic rice for export. Picture: Trung Chanh.
However, rice shrimp production in Kien Giang is still unsustainable, with about 40,000 hectares of farmers still not replenishing rice crops every year. Year-round aquaculture will disrupt the farming system and lose the superiority and sustainability of the model. Therefore, there is a need to find solutions that will help farmers replant the rice crop, improve the environment and support effective shrimp farming.
As part of agricultural restructuring, Kien Giang Province continues to plan and convert another 20,000 hectares of coastal rice land south of National Highway 80 from Hon Dat to Kien Luong to expand the acreage according to the rice cultivation system. – Shrimp, helping to improve rural income.
Produce early to avoid El Nino
According to the forecast, the El Niño phenomenon will return around June this year and last until the dry season of 2023-2024. Drought and salinity will increase, which poses a major challenge for model rice production. Rice – shrimp due to the threat of freshwater shortages at the end of harvest. Therefore, it is necessary to ensure a reasonable crop, sow the seeds earlier than each year, and use salt-tolerant rice varieties to limit potential damage.
The shrimp-rice model has confirmed its superiority and sustainability, but the fact that farmers in the model forgo rice cultivation in order to produce year-round aquatic products risks disrupting this farming system. Picture: tsp.
Mr. Le Van Khanh, head of the Ministry of Agriculture and Rural Development of An Minh District, said farmers in the district have switched their production to the rice-shrimp model for over 20 years, from 2001 to now. The district has a well-organized production planning from the beginning. So far, the rice shrimp production model is stable and provides a good source of income. At present, the whole district has an aquaculture area of more than 47,000 hectares, of which 39,000 hectares are devoted to the production of rice shrimp models, the acreage for rice cultivation is over 25,000 hectares.
In recent years, effective rice production has helped the rice-shrimp model become more and more effective and sustainable. In aquaculture, the farming method was gradually extended to improved shrimp – rice combined with giant freshwater shrimp or sea crab. As for the rice production, the 2022-2023 crop alone was planted and harvested on a large area of almost 25,580 ha, with an average yield of 5 tons/ha, with a production of 130,370 tons, with ST varieties accounting for 30% of that The rest are seasonal rice varieties and some other high-yielding rice varieties.
In particular, to implement the rice-shrimp value chain, many companies have made agreements with agricultural cooperatives in the district to invest in nearly 1,000 hectares of certified organic rice production and link up with rice production. More than 2,000 hectares of shrimp cultivation area. Cooperatives in the region also have rice consumption contracts with companies like the Dai Duong
After each shrimp breeding culture, the field environment creates many favorable conditions for the growth of rice plants. Picture: tsp.
Prof. Dr. Nguyen Bao Ve (Can Tho University) said at the workshop that rice plays a very important role in the rice shrimp farming system, helping to clean the environment and balance the ecosystem. field thai. In the dry season, we need to bring salt water to the field to create a brackish water environment for shrimp farming. When it rains, the salt needs to be expelled to create a sweet environment for growing rice.
Only brackish water can be bred for shrimp, in addition to breeding in the field, rearing can be done in ponds and lakes with rubber tarps. However, in addition to fresh water, rice plants also need a soil environment that is not contaminated with salt, alum, etc.
Therefore, the stage of soil salinity is very important to effectively replant the rice crop. Do not let the soil dry out during cultivation, otherwise salt water can penetrate deep into the soil. It is necessary to plow the topsoil to wash the saline alum and dig ditches to create conditions for the saline alum to drain. At the same time it is necessary to fertilize with calcium and organic to remove salt from the soil…
Engineer Ho Quang Cua – the “father” of ST rice varieties, such a sad reality: Currently, ST rice varieties are often counterfeited, for example, in the district of An Bien (Kien Giang), the rice and shrimp harvest is mediocre. Miss it on 60-70%.
ST rice related to the rice-shrimp production model is considered an excellent specialty, but also faces challenges due to the problem of inferior ST varieties, which are difficult to control.
The shortage of ST rice varieties for production is due to an increase in production area, while ST25 rice has won the Best Rice in the World award, so “piracy” is happening everywhere, in the US, Australia and even in Vietnam Plenty of time to protect. The more ST rice varieties attract goods, the more counterfeiting occurs. Not only the rice seeds are packed in white bags, but also the packaging is imitated, the farmers are deceived and deceived. Damage caused by inferior rice varieties.
The rice shrimp cultivation system is a very ideal environment for organic rice production as it is less polluted by chemicals. Thanks to the rice-shrimp rotation, the isolation and harvest pause time is very long, eliminating the source of disease transmission from the previous crop to the next crop.
After the shrimp harvest, the remaining organic matter in the soil serves as a nutrient source that supports the growth of the rice plants, thereby reducing fertilizer costs. On the contrary, rice will purify the environment for shrimp farming, and the decomposed straw and straw will create an environment for the growth of many species of organisms, thus providing food for extensive shrimp farming.
“In the coming period, Kien Giang Province will focus on reorganizing production, investing in the development of shrimp farming toward organic, ecological shrimp, and investing in infrastructure to expand rice shrimp farming area.” Le Van Dung, deputy director of Kien Giang Agricultural Extension Center said.