It was her husband's last wish: to continue planting trees. 

Niu Yuqin was only 17 when she married Zhang Jiawang in the poor farming village of Jinjisha, located near the Maowusu Desert in China's northwestern Shaanxi Province. Making ends meet in the remote region had been a challenge, let alone the harsh terrain and weather conditions that keep devouring their crops and land.

"It (the desert) kept advancing on our farmland little by little, inch by inch. We starved because of poor harvests," Niu explains. 

By trial and error, when they realized that trees could survive in deserts, the couple borrowed 4,000 yuan from a bank in 1984 to hire workers and buy saplings for planting. They even sold off personal valuables to continue financing their initiative.

Four years later, Zhang succumbed to bone cancer, leaving Niu behind to fend for their three young sons and his elderly parents.  

Niu soldiered on with the tree-planting project, at times, taking on extra jobs to meet financial needs. In 1998, Niu opened her own company to breed trees and livestock.

Three decades on, more than 28 million trees along with various types of crops, vegetables, and fruits cover some 7,300 hectares of once barren lands.

Niu's achievements in desert control along with subsequent contributions to society have been lauded both at home and abroad.  

Hailed as the "Sand Hero," Niu has won dozens of local and national honors. In addition, the UN Food and Agriculture Organization gave her an award for Outstanding Accomplishment in the Conservation and Use of Genetic Resources in 1993.

Nowadays, Niu's third and youngest son, Zhang Liqiang leads the anti-desertification initiative. As the CEO of Luyuan Desert Control Co. Ltd., Zhang constantly upgrades tree-breeding and farming practices. He uses solar-powered or photovoltaic water pumping systems for irrigation. Also, he flies a high-tech drone to survey the desert conditions and crop yields. 

"I try to be a role model for our children, so that they will voluntarily continue the fight against desertification," Zhang says.  

Among those likely to take over the family tradition is Zhang's son who is currently majoring in forestry.

"The barren lands have been turned into an oasis," Niu tells us proudly, adding that their homeland will only flourish in the future.

Niu, now 70, still tries to walk 20,000 steps every day. And everywhere she goes, she carries a small bell, a gift from her late husband, in lieu of a wedding ring. Seeing her smile while ringing the bell was a heartwarming reminder of how an individual's labor of love for her family can inspire and impact the lives of millions of people. 

(CGTN's Dai Piaoyi contributed to the story)