Smart rice farming slashes over 3.7 tonnes of carbon/ha

Reduced costs, reduced emissions

In 2025, the Thai Nguyen Sub-Department of Plant Production and Protection, in coordination with Net Zero Carbon Company and the Hop Thanh Commune People's Committee, implemented a smart rice cultivation model spanning 12 hectares. This model employs Alternate Wetting and Drying (AWD) irrigation to reduce methane emissions and aims toward developing agricultural carbon credits.

Farmers participating in the model cultivate rice using the Alternate Wetting and Drying (AWD) irrigation technique and the System of Rice Intensification (SRI) method. Farmers transplanted young seedlings (2 leaves), used sparse planting, planted single tillers, practiced intermittent water drainage, and applied fertilizer early and at the correct time. Rice growers actively monitored and calculated the precise timing for using plant protection products to manage pests and diseases, and applied Integrated Plant Health Management (IPHM) in the rice crop.

Unlike traditional cultivation, which usually maintains continuous flooding, the AWD technique involves keeping the fields flooded only four times (4, 22, 40, and 64 days after transplanting), followed by natural drainage and drying the fields. This practice of draining water and drying the fields helps supply oxygen to the roots, promoting better respiration and nutrient absorption. It also encourages the rice plant roots to penetrate deeper into the soil in search of water and nutrients.

Drying the fields allows the rice root system to develop robustly and spread widely, giving the plant greater resistance to adverse conditions such as drought, waterlogging, or strong winds. Furthermore, applying AWD helps reduce methane (CH4​) emissions, a potent greenhouse gas, which typically results from the anaerobic decomposition of organic matter in continuously flooded rice paddies (a condition of oxygen deficiency).

Mr. Hoang Thanh Binh, Deputy Director of the Thai Nguyen Sub-Department of Plant Production and Protection, stated: The smart, Alternate Wetting and Drying cultivation model demonstrates superiority in agronomic indices. Across all growth stages of the rice plant, indicators related to roots, stems, leaves, and tiller count in the model fields showed better development compared to the conventionally cultivated control fields. The rice yield achieved by applying this low-emission cultivation method was 15% higher than conventional farming.

"Seed costs were reduced by 50%, nitrogen fertilizer by 20%, plant protection product costs by 30%, and irrigation water use was estimated to decrease by 40%. Due to the higher yield and reduced costs, the profit for smart rice farmers increased compared to traditional farming. Additionally, farmers gain extra profit from the circulation of straw, which is used as on-site organic fertilizer, and from transactions based on emission reduction reports," Mr. Binh added.

According to the research unit implementing the project, the 12 hectares of low-emission rice cultivation in Hop Thanh commune successfully reduced carbon emissions by over 44.5 tons, averaging more than 3.7 tons per hectare.

Given these positive results, the smart, alternative wetting and drying, methane-reducing rice cultivation model, which aims to develop agricultural carbon credits, aligns perfectly with the strategic direction of advancing low-emission crop production, adapting to climate change, increasing income, improving sustainable livelihoods, and gradually forming an ecological agriculture.

Adding support policies for farmers

In the coming period, the Thai Nguyen agricultural sector will continue to scale up the model in areas with suitable production conditions, while assessing its effectiveness as a basis for wider replication across the province.

Based on practical experience, Mr. Hoang Thanh Binh, Deputy Head of the Thai Nguyen Sub-Department of Plant Production and Protection, proposed the development of additional policies to support farmers with microbial products for treating agricultural by-products, the cultivation of indigenous microorganisms, and the use of bio-fertilizers, microbial fertilizers, as well as secondary and micronutrient fertilizers for crops. He also emphasized that the province should promote the adoption of single-variety fields, with uniform sowing schedules and consistent farming practices, to improve efficiency.

During the pilot model implementation, several challenges also emerged. Irrigation and drainage systems in small, fragmented cultivation areas are difficult to operate effectively. Regulating water using the alternate wetting and drying method requires precision and synchronization with the crop calendar, which is challenging in fields with scattered, small-scale irrigation infrastructure, limited control over water supply and drainage, or in low-lying areas with poor drainage.

In addition, differences in awareness, access to information, and traditional farming practices, along with farmers’ reluctance to change, have led to inconsistent adoption of cultivation methods, making large-scale implementation difficult within a short timeframe.