Vietnam seeks solution to re-use rice straw
Việt Nam is wasting millions of tonnes of straw every year, which can instead be used to make useful fertilisers and protect the environment
According to report by International Rice Research Institute (IRRI), some 44 million tonnes of straw in the country are disposed or burnt every year, which can be used to produce an environment-friendly fertiliser to enrich the soil, fertilise other crops and plant mushrooms.
“Burning of straw can increase greenhouse gases two to three folds compared to fertilisers,” said Bùi Quang Đăng of the Vietnam Academy of Agriculture Sciences. “Even if just half of the straw is burnt, 100 million tonnes of CO2 will be released in the environment every year.”
According to Đăng, a tonne of fertilised straw contains 10kg nitrogen, 9.5kg phosphorus and 21kg potassium.
Therefore, 44 million tonnes of straw that are being wasted in Việt Nam every year can produce 20 million tonnes of organic fertilisers, including 200,000 tonnes of nitrogen, 190,000 tonnes of phosphorus and 460,000 tonnes of potassium, Đăng said.
According to him, if farmers sell the straw instead of using it for their crops, they will suffer a loss as their next season of crops is unlikely to thrive without the straw, and the monetary gain from the sale of the straw is not worthwhile either.
He added that organic fertilisers were more effective than chemical fertilisers as the former dissolved into the soil much slower, benefiting the plant.
A straw managing project by BMZ-IRRI has been deployed since February 2016 to aid farmers on the straw-collecting process and related business. The project has raised the collected straw by half in Cửu Long (Mekong) River Delta, thus reducing the burning of straw by 50 per cent.
The project will be developed further to produce biogas and Urea straw for cattle as well as to plant mushrooms, with an estimated profit of US$50-100 per tonne. Other positive effects will include eco-friendly technological applications and sustainable agriculture.
IRRI’s Martin Gummert, head of the project, said after two years of implementation, the project helped solve problems in increasing the value chain, connectivity among parties in rice production, by-products and value of sustainable rice production.
Đăng, however, mentioned many drawbacks, such as difficulties in collecting the straw, transport process and investments needed for fertilising machines.