Organic farming plants bring hope for green future

Photo taken on Jan. 13, 2022 shows a recycling station of organic waste in Liangzhou District, Wuwei City, northwest China's Gansu Province. [Xinhua/Fan Peishen]

LANZHOU -- With tomato seedlings growing half a person high, biogas manure like a black snake reached the deep roots of the green branches in a zigzag stream from a plastic vat at the door of a solar greenhouse.

For farmer Han Dengping, biogas manure is a novelty. When a recycling station in his hometown in Liangzhou District, Wuwei City, northwest China's Gansu Province, offered to provide biogas fertilizer free of charge last November, Han decided to give it a try with a grain of salt.

"There has been no yellowing at the top of tomato seedlings so far, showing they are growing well," he said.

Xin Yixi, a farmer in Liangzhou's Huangyang Village, however, has taken one step ahead of Han and bid farewell to his long-kept planting habits years ago.

For convenience, Xin and his fellows used to dump the cattle and sheep manure into the cornfield as one of the fertilizer sources.

"It indeed saved a lot of effort, but the problems of soil hardening, maize pests and diseases brought by the feces of animals were very worrying," Xin said.

A panacea that could help the farmers get the best of both worlds came in 2016 when the recycling station was built up in Liangzhou District, aiming to collect organic wastes including food residue, rotten vegetable leaves and livestock manure to produce marsh gas and biogas manure, among others.

"We are trying to transform the waste into treasures," said Guo Wei with the company operating the recycling station.

The station can process more than 80,000 tonnes of organic waste annually and generate 6.5 million kilowatt-hours (kWh) of electricity a year, according to Guo.

To arouse farmers' enthusiasm, Guo's team adopted a barter system in 2018, in which local farmers can take cattle and sheep manure and maize straws to the station in exchange for biogas fertilizer.

"Considering the different planting habits and land conditions of each farmer, we distribute customized biogas fertilizers after technicians conduct a sample analysis on their soil and scientifically add corresponding components to the biogas manure," Guo said.

Living only one km away from the recycling station, Xin was among the first batch of villagers in great haste for the service in 2018.

In the following year, the seedling emergence rate of Xin's cornfield had increased by 20 percent, and he also saved about 5,000 yuan (about 789 U. S. dollars) in fertilizer expenses.

"It's like magic," Xin said.

Besides the recycling station near Xin's home, Liangzhou District is now home to a total of five recycling stations, processing 291,000 tonnes of organic waste, producing 13.5 million cubic meters of biogas and generating 19.27 million kWh of electricity annually.

"Changing farmers' planting habits is one of the keys to achieving low-carbon and green development, as the country aims to peak its carbon dioxide emissions before 2030 and achieve carbon neutrality before 2060," Guo said.