By Xinhua writers Sun Zhiping, Li Binian and Liu Huaipi

ZHENGZHOU, March 18 (Xinhua) -- In 1855, the Yellow River, China's mother river, changed its course again.

The loss of the vital water source left the land barren with thousands of moving dunes threatening to swallow the grain-growing plain near the old river course in Shangqiu City, central China's Henan Province.

Since Minquan Forest Farm was established in Shangqiu in 1950 to combat the moving sand dunes, local people have taken 67 years to extend 4,600 hectares of "green barriers" to stop the sand encroaching.

Tong Chaoran, 80, came to Minquan Forest in 1962 after graduating from the Beijing Forestry University, and has worked there ever since.

"In spring, we planted trees day and night in the farm without going home. We hid in a cellar that we dug in the sand to stay overnight, and ate nothing but dried sweet potatoes and radish," he said.

By then, nothing could be harvested due to sweeping sandstorms. Houses and farm fields could be buried in sand overnight.

With incessant tree planting, the farm has achieved annual growth of forest averaging 17,000 cubic meters in the past years. The forest now has a total area of 187,000 cubic meters, said Wang Wei, director of the farm.

There are more than 100 varieties of plants in Minquan Forest Farm. Wardens have spotted more than 180 kinds of animals in the forest, with 16 listed as state protected animals.

The trees can preserve wetland and lakes. The ecosystem is able to protect 80,000 hectares of farmland, and absorb 22,500 tonnes of carbon dioxide a year.

Because of the ecological transformation, an area of 2,877 hectares on the farm was turned into a national ecological park in 2015, with the approval of the State Forestry Administration.

Flowers and rare birds, as well as picking grapes, pears, apples and walnuts in the forest helped the county's tourism. In general, the forest business increases people's income by 696 million yuan (109 million U.S. dollars) a year.

A plan to plant another 2,400 hectares of forest along the old Yellow River course is on the government agenda.

The government launched bidding in 2017 to invite contractors to plant trees in an area of 1,282 hectares and maintain 16,500 trees already planted.

"We put emphasis on green development, and attach equal importance to protection and development. The forest in the future is for our delight and health," said Ji Maichang, Party Chief of Minquan County.