A random check is also made once a week.

Supervisors rate every household's performance and award a mark, and once a month the total of marks can be converted into grocery purchases such as laundry detergent, toilet paper and cooking oil.

Yu says the village has spent more than 20,000 yuan ($3,100) a month on such awards over the past half year.

At the end of the year, villagers' performance in keeping their environment clean can be taken into account in naming exemplary families, with cash bonuses being awarded.

One of the villagers, Li Rongchun, said that at first there was a wide divergence in the performances but over time villagers' waste handling has improved, and most families perform well enough to be able to win the maximum number of points.