Brian Jeffrey
In Vietnam, the rice cultivation industry spans 7.1 million hectares, making it a major global rice producer with an annual yield of about 41-43 million tons. This output not only meets local demand but also supports the export of 7-8 million tons of rice annually.
Rice farming is the primary source of CO2 emissions in Vietnam’s agriculture, contributing 39.1% of the 90 million tons of CO2 emitted each year. Dr. Minh Hai Tran from the School of Public Policy and Agricultural Development states that emissions in rice farming result from the use of fertilizers, pesticides, irrigation practices, and particularly the management of straw.
Burning straw depletes soil nutrients, reduces biodiversity, and pollutes the environment, while burying straw in wet fields increases greenhouse gas emissions, especially methane, which is more potent than CO2.
The Mekong Delta, Vietnam’s leading rice-producing region, generates approximately 24 million tons of straw per year, with only 30% or about 7 million tons being collected and utilized. The remaining 17 million tons are often burnt or buried, leading to wastage of agricultural by-products and environmental pollution.
To tackle this issue, the Ministry of Agriculture and Rural Development, in partnership with local governments, is initiating a project to develop 1 million hectares of high-quality, low-emission rice farming linked to green growth in the Mekong Delta by 2030.
The project aims to reduce emissions by decreasing seed, fertilizer, and pesticide use, implementing alternate wetting and drying irrigation methods, and managing straw to minimize emissions, resulting in substantial reductions in methane and other greenhouse gases.
Initial pilot results show positive outcomes. Seed usage has decreased from 140kg to 60kg per hectare, fertilizer application has been reduced from 3-4 times to twice per crop, and inorganic fertilizer use has dropped by at least 20%. Pest problems and post-harvest losses have also decreased, with rice from these models fetching a higher price compared to conventionally grown rice.
Instead of burning or burying straw, farmers are now rolling and removing it from the fields, selling it for 400,000 VND per hectare. This practice not only enhances soil health and boosts farmers’ income but also opens up opportunities for straw reuse in various applications.
The pilot models have demonstrated a decrease in greenhouse gas emissions, cutting emissions by 2-6 tons of CO2 equivalent per hectare compared to traditional fields.
Efforts are underway to measure, report, and verify greenhouse gas reductions in rice farming, with plans to eventually trade carbon credits for economic benefit.
Collaboration with the Transformative Carbon Asset Facility aims to price carbon credits at 20 USD per credit, enabling farmers to reduce emissions by 30%, equivalent to two carbon credits, resulting in a monetary advantage of 960,000 VND.
Viewing straw as a valuable input for various industries in a circular economy, its uses range from livestock feed to mushroom growth substrate, offering additional income opportunities for farmers.
By utilizing straw for mushroom cultivation or organic fertilizer production, farmers can significantly increase their income per hectare, showcasing the economic potential of proper straw management.
Properly managing straw not only lowers greenhouse gas emissions but also enables farmers to earn extra income through carbon credits, straw sales, and its utilization in various applications.
On the contrary, continuing to bury straw in wet fields will lead to increased emissions and missed income opportunities for farmers.
