BEHIND THE WHITE SMOKE: THE “SILENT” AGENT OF AIR POLLUTION

When it comes to air pollution, we often think of car smoke, smoke from factory chimneys, or dust from construction projects,… However, behind that conspicuous white smoke, there is a “silent agent” that is quietly covering the atmosphere, which is the burning of straw harvested after each harvest. This seemingly harmless activity produces large amounts of PM2.5 fine dust, toxic gases, and greenhouse gases,… are factors that contribute to the deterioration of air quality, threaten public health, cause economic losses, and hinder efforts to respond to climate change.

Why do farmers still burn straw?

Some habits go deep into the subconscious, when the picture of memories in the countryside throughout Vietnam has piles of straw, all waiting after harvest to burn the straw. Many children wait until this time to have fun in the fields, playing with smoke as a habit and as an idyllic childhood beauty. Every child grows up like this; families involved in agricultural production have such a habit, and even if the smell of smoke is unpleasant, it is very rare for anyone to notice it.

In many localities, farmers still apply straw burning because it is fast, convenient, cheap… 

The consequences of burning straw, causing dense smoke to spread, deteriorate urban air quality, especially in adverse weather conditions. Studies estimate that the majority of rice straw in Vietnam is still burned in the fields, creating significant emissions. According to Mr. Le Hoai Nam – Deputy Director of the Department of Environment, Ministry of Agriculture and Environment, the winter from October to April is the time of the most serious impact due to pollutants that are difficult to diffuse. The burning of rice straw produces PM2.5, CO, NOx, and PAHs,… are the causes of respiratory and cardiovascular diseases and increase the rate of premature death.

Farmers still keep the “traditional” habit of burning straw, despite the ban

Mr. Hoang Duong Tung, Chairman of the Vietnam Clean Air Network also said: The current regulations and management plans are not strong enough, while the monitoring capacity at the local level is still weak. Therefore, despite the ban, farmers still burn straw because of the lack of viable alternatives. This situation is not only in Vietnam but also common in India and many other agricultural countries.

A feasible solution, not just banning, is done

According to a report by the Indian Institute of Agricultural Research, the recommendation to disseminate machinery such as cultivators, straw presses, plows,… to reduce the need for incineration, at the same time, take advantage of straw as bioenergy, processed animal feed, or decompose directly in the field to supplement soil nutrition, along with subsidy policies and support for the implementation of technology dissemination models,  machine leasing, centralized leasing,… will be more effective than applying “no burning” measures.

Similarly, Vietnam has also applied a number of policies to support renting machinery and equipment, buying straw, supporting farming conversion, etc. However, to promote effectiveness, the policy needs to be stabilized for a long time because agricultural equipment has a high price and is difficult to access for low-income farmers. In parallel, it is necessary to combine satellite monitoring technology to detect fire points and flexible sanctioning mechanisms, but more importantly, there must be a parallel livelihood solution for people.

Experts in the GAHP Project come to evaluate the green agriculture model of farmers 

In Vietnam, in addition to programs aimed at reducing emissions, there are also many foreign partners participating in supporting Vietnam in solving problems of air pollution, reducing greenhouse gas emissions, developing a carbon exchange market, etc. Among them, there is an international initiative that is supporting the solution to reduce emissions from burning straw that causes air pollution, which is the Global Alliance on Health and Pollution (GAHP), funded by DEFRA (UK), in collaboration with the Vietnam Association for the Protection of Nature and Environment (VACNE). This program focuses on research, piloting intervention models, and raising public awareness to reduce air pollution, improve the rural environment, and move towards “green” and sustainable agricultural farming.

Models successfully piloted

A typical model implemented by the GAHP Project from 2023 in Song Ray commune (Cam My commune, Dong Nai) has helped farmers be instructed to use microbial preparations to treat rice straw instead of burning it. The straw after microbiological treatment helps reduce ghost rice, increase yield, reduce fertilizer, help improve soil, reduce smoke, and shorten the decomposition time to 14-15 days. If in the past, in 1 season, farmers used 40kg of fertilizer for one application, now only 30kg is used.

Rice straw, after being used by farmers, has increased productivity and increased income for farmers

Or another typical example is the household of Mr. Nguyen Thanh Ha (An Giang), taking advantage of straw to grow mushrooms. After a while, the family’s income reached more than 20 million VND/month, significantly higher than rice cultivation alone. In particular, the model in Chau Thanh commune (An Giang) has shown that an integrated approach can create significant changes. Here, 12 households were supported by GAHP, VACNE, and partners to implement the following models: Composting rice straw into organic fertilizer (scale 8-20m3, 25-80 straw rolls); Composting straw with urea for animal feed; Growing straw mushrooms indoors (scale 20 – 300m2, using 40-500 straw rolls),… After deducting the initial investment costs, each crop participant will have an additional income of 3-5 million VND.

After one crop, households increase their income by 3-5 million VND from the composting model and 3-12 million VND from the mushroom cultivation model. In addition, the straw rolling service brings an additional 500,000 VND/ha and significantly reduces the amount of straw burned. Residents also receive technical training, provision of microbiological preparations, cost assistance, and community communication to amplify impact.

Farmers use microorganisms in a project funded by DEFRA/GAHP to help increase rice yield efficiency 

ASS. Dr. Phung Chi Sy – Vice Chairman of the Vietnam Association for the Protection of Nature and Environment said: “One of the outstanding results in the project has been the research, development, and pilot application of alternative technologies to reduce open burning, sustainable agricultural practices, and the circular economy. Along with that, the project has selected a short list of 12 technological processes to be evaluated according to scientific criteria and in accordance with Vietnamese practice.

With 6 types of alternative technologies selected, the type of alternative technology to be piloted within the scope of the project from previous years such as: Mushroom cultivation using post-harvest straw; developing the process of collecting and composting straw for organic fertilizer at households using Trichoderma probiotics; processing straw with urea for fodder; raising worms on rice straw that has been cultivated with mushrooms; compost rice straw as fertilizer right in the field to use and use multi-strain and multi-functional biological products developed by the Institute of Agricultural Environment; the process of making organic fertilizers adapted to rice farming right in the field, using probiotics developed and produced by Nguyen Tat Thanh University”.

Farmers need to be aware of changing the behavior of “open burning” to protect health and the general environment

The models implemented by GAHP and its partners have in common that they are easy to adopt, low-cost, have clear outputs, and are supported by hands-on techniques. And turning rice straw from a “waste product” into a real source of income has helped reduce straw burning, improve air quality, as well as build a circular agriculture model.

If replicated with appropriate support policies, clear technical solutions, and sustainable market mechanisms, farmers can completely switch from the habit of burning straw to a green and environmentally friendly farming model. This is also an important step to help Vietnam both protect public health, contribute to reducing greenhouse gas emissions, and effectively adapt to climate change.

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