soil moisture, reduce overall vegetation cover, and lead to more severe wind erosion (10). The one-child policy, started in 1979, responded to inaction that had led to a population of 975 million, 80% higher than in 1949 (11). It averted more than 300 million births by 2005 (8), which has had debatable social effects but can be seen as beneficial to the environment. However, the number of households has increased much faster than the population since 1979 owing to such factors as more divorces and a lower proportion of multigenerational households. Reduction in household size alone added 80 million households from 1985 to 2000 (12). More households consume more resources and generate more waste, and smaller households lower the efficiency of resource use.

 

What will China's future road to sustainability look like? It will depend on the timing, durations, strength, and complex interactions of existing and emerging forces in China and elsewhere. Bolder actions are needed to weaken negative impacts and to strengthen positive ones. Here are two examples: Efforts to promote environmental sustainability should be a major criterion for evaluating government officials nationwide (13). More sustainability actions should take place in households, the basic socioeconomic units of consumption. Households can increase resource use efficiency and reduce emissions in many ways (14). Formation of new households can be slowed by discouraging divorce (e.g., implementing a longer waiting period for couples seeking to divorce) (15). Government incentives such as tax credits and subsidies can promote co-housing and thus increase sharing of household goods.

 

China's transition to sustainability should take advantage of its ability to implement massive programs that can infiltrate every aspect of society rapidly. Furthermore, China's economic strength gives it an unprecedented opportunity to become a global leader in sustainability through institutional, scientific, and technological innovations.