New rice irrigation methods: Many benefits, easy to replicate.

Three trial production cycles have shown that the alternating wet-dry irrigation technique in rice cultivation in Hai Duong has great potential for expansion and brings many benefits.

Officials from the Center for Organic Agriculture (Vietnam Academy of Agriculture) inspect greenhouse gas measuring equipment at a rice cultivation model using alternating wet-dry irrigation techniques in Tan Quang commune (Ninh Giang).

Ensuring productivity and saving costs.

During the 2023-2024 winter-spring crop season, the Hai Duong Department of Agriculture and Environment, in collaboration with the Vietnam Academy of Agriculture and Green Carbon Japan Vietnam Co., Ltd., launched a pilot model for rice cultivation that reduces greenhouse gas emissions through irrigation water management on an area of ​​3 hectares in Tan Phong commune (Ninh Giang district). The model will continue to be implemented in the same commune on the same scale during the 2024 crop season.

For the 2024-2025 winter-spring crop season, this model will be further expanded to three communes: Tan Phong, Tan Quang (Ninh Giang district), and Ngu Hung (Thanh Mien district), covering a total area of ​​nearly 1,000 hectares.

Ms. Luong Thi Kiem, Deputy Director of the Department of Agriculture and Environment of Hai Duong province, said that the technique of reducing greenhouse gas emissions in rice cultivation through alternating wet and dry irrigation is not complicated and is very easy to implement.

During the tillering stage of rice, farmers maintain a stable water level of 1.5-2 cm in the field. When the rice finishes tillering, they drain all the water from the field to help the rice roots develop deeper and stronger, to keep the field well-ventilated, and to reduce pest and disease damage.

From the heading to flowering stage, continue supplying water to the rice field to nourish the grains. After the rice has finished flowering, drain the water to allow the rice to ripen quickly, the field surface to dry, and harvesting to proceed smoothly.

"The inspection and evaluation results show that this year's winter-spring rice crop in the models is estimated to yield about 70 quintals/hectare, higher than the province's average yield by 2-2.5 quintals/hectare. More importantly, the alternating wet-dry irrigation technique in rice cultivation brings many other benefits," Ms. Kiem said.

Rice yields in the 2024-2025 winter-spring season in Hai Duong province, using alternating wet-dry irrigation techniques, are higher than the province's average yield.

Mr. Pham Cong Dung from Xuan Tri village, Tan Quang commune, who participated in the model, shared: "Applying this technique, there were times when the rice fields were so dry that they cracked, so at first we were worried. But later, we saw that the rice plants were strong, had fewer pests and diseases, and didn't fall over during the recent heavy rains, while the yield remained stable, so we are very happy."

Studies estimate that rice cultivation consumes approximately 34-43% of agricultural irrigation water, contributing up to 48% of greenhouse gas emissions and 75% of _CH4 emissions in agriculture...

According to expert assessments, cultivation techniques that reduce greenhouse gas emissions, such as alternating wet and dry irrigation, significantly reduce the amount of water used for rice cultivation and irrigation costs for farmers, while increasing tillering capacity, leaf area, and dry matter accumulation. Rice cultivated using this technique also helps reduce pests and diseases, especially brown spot disease, thereby reducing production costs for farmers.

In particular, this farming method has significantly reduced emissions compared to traditional flooded rice farming (50.2%), equivalent to 7.6 _tCO2 e/ha (a unit of greenhouse gas measurement), creating carbon credits and contributing to the national goal of sustainable rice farming and greenhouse gas emission reduction.

Continue to expand

Dr. Vu Duy Ngoc (second from the left), along with leaders from the Department of Agriculture and Environment, all agree that Hai Duong province and Hai Phong city currently have many favorable conditions to expand the area of ​​rice cultivation applying the alternating wet-dry irrigation technique.

Dr. Vu Duy Hoang, Deputy Director of the Center for Organic Agriculture (Vietnam Academy of Agriculture), said that the alternating wet-dry irrigation technique applied to reduce greenhouse gas emissions has been implemented in Vietnam since 2003 in several provinces and cities.

Previously, these models primarily focused on water conservation and increased productivity. In recent years, as the world has become more concerned about climate change, emission reduction, and carbon credit creation, rice production using these techniques has become more widely adopted.

The Vietnam Academy of Agriculture has researched, developed, and perfected the alternating wet-dry irrigation technique and implemented it in many provinces and cities, including Hai Duong and Hai Phong.

Authorities assess that Hai Duong currently has great potential to replicate this model, as the annual rice cultivation area consistently remains at around 53,000 hectares, the land is flat, the soil quality is generally good, and the irrigation system is quite comprehensive, making it favorable for cultivation.

The alternating wet-dry irrigation method requires flexible water management according to each stage (illustrative image).

Hai Phong currently has approximately 41,000 hectares of rice cultivation land. In a short time, when Hai Duong province and Hai Phong city merge, the total area of ​​rice cultivation land will increase even further. If the alternating wet-dry irrigation technique is applied uniformly, it will contribute to a significant reduction in CH4 emissions, which can then be converted into carbon credits and potentially participate in the carbon credit market mechanism, increasing farmers' income.

According to Ms. Kiem, to sell carbon credits from rice production, it is necessary to maintain cultivation on at least 10,000 hectares applying the alternating wet-dry irrigation technique. The province's goal is to continue expanding these models to many other localities in subsequent rice seasons. This is not too difficult because the technique is easy to implement. However, to expand the model, it is necessary to change the mindset and farming habits of farmers.

Dr. Vu Duy Hoang believes that to replicate the model, agricultural service cooperatives need to continue disseminating information so that farmers understand and agree to participate. During implementation, the Organic Agriculture Center is ready to cooperate and provide hands-on guidance to farmers. After just one season, farmers will grasp the techniques and gradually develop new farming habits.

Besides ensuring productivity, the alternating wet-dry irrigation technique in rice cultivation also contributes to reducing emissions, creating carbon credits, and providing additional income for farmers if widely implemented.

On January 24, 2025, the Prime Minister signed Decision No. 232/QD-TTg approving the Project on establishing and developing a carbon market in Vietnam. Along with related policies soon to be implemented, the alternating wet-dry irrigation technique in rice cultivation can be widely adopted.

TIEN MANH

Source: https://baohaiduong.vn/tuoi-lua-kieu-moi-nhieu-gia-tri-de-nhan-rong-414862.html