When he was 66, he went to the Hua'e Mountain, the highest in the northeastern part of Sichuan where the environment had deteriorated.

"Many trees were being felled, and wild animals were being hunted. I decided to protect the mountain and slowly restore its environment," Zhou said.

At first, the villagers disliked Zhou because he told them not to cut down trees or hunt animals for money.

"I promoted conservation education among villagers, and they realized their mistakes. Finally, they pledged not to cut down trees or hunt," Zhou said.

He used his own savings and raised funds to pay villagers to plant trees. His efforts have paid off as the mountain is now green and lush.

To restore the mountain's environment, Zhou spent more than 10 years living in thatched cottages that he had bought.

Once, when he was 78, he fell when he was patrolling the mountain to investigate the forests. He was rendered unconscious and lost a lot of blood.

"Later, I learned nine villagers carried me down a dangerous mountain path to reach a hospital 4 kilometers away, which saved my life. The story confirmed the belief that common people won't treat us as outsiders if we members of the CPC treat them well," Zhou said.

Zhou was born into a poor family in Bazhong. His mother passed away when he was 6. Both his grandfather and father had to support the family as farm laborers hired by the year.

As a result, he is very thrifty. He has lived in an old apartment for 36 years and has used an old sofa given to him by his son for 20 years. But each month, he gives half his wages to needy students, Li said.

In 2014, Zhou went to a primary school in Bazhong where he had been a student and saw a boy sitting alone in one corner of the playground. He found the student had a strong sense of inferiority because his family was poor.

Zhou encouraged him not to be deterred by poverty and muster up courage instead. Since then, Zhou has sent 3,000 yuan ($463) to the school the boy attends whenever the new semester starts.

On Feb 13 last year, amid the throes of the COVID-19 epidemic, Zhou and his wife, Wu Yingming, donated 100,000 yuan to the Red Cross Society of China and asked it to give the money to people working on the front lines of the battle against the disease.