THE ENVIRONMENT UNDER MAO ZEDONG

-- Harnessing nature for agricultural production was a key goal for Mao Zedong's communists, who took power in 1949.

-- Workers were deployed to the countryside's newly collectivised farms during the 1958-1960 Great Leap Forward. The now-discredited ideas of Soviet biologist Trofim Lysenko were championed to boost harvests, and entire mountains were moved by peasant labour for irrigation schemes.

-- Campaigns such as the "war on the four pests", to eliminate rats, flies, mosquitoes and sparrows, took a toll as locusts ate grain crops, plunging parts of China into famine.

RAPID INDUSTRIALISATION:

-- China's late 1970s transition from a planned to market economy saw it open its doors to industry, under an officially endorsed "development first, environment later" policy.

-- Cars replaced bicycles as wealth grew in eastern seaboard cities that attracted millions of migrants keen to "catch up" with Western economies. Power plants, refineries and chemical factories sprouted. Plentiful, polluting coal, which supplies about two thirds of electricity, fuelled the drive to modernise.

THE RISE OF ENVIRONMENTAL AWARENESS:

-- UN figures showing China is home to 16 of the world's 20 most polluted cities raised alarm overseas. Worsening air pollution from factories and transport as well as sand storms from the Gobi Desert have annoyed China's neighbours for years.

-- Inside China, natural disasters and several mid-1980s protests against dams and power plants by disaffected villagers saw awareness rise about environmental problems.

-- China's first legal green NGO, Friends of Nature, was founded in 1994, a decade and a half after the World Wide Fund for Nature (WWF) became the first conservation group to work in China in 1979.

A SENSITIVE SUBJECT AT HOME:

-- Resource-based conflicts remain a sensitive subject for authorities who fear protests over pollution might upset social stability by breeding discontent with the ruling Communist Party.

-- China established the State Environmental Protection Administration in the 1990s and it now has several strict environmental laws. While critics say the problem is enforcement, scandals such as the Nov. 2005 Songhua River disaster, where chemicals poisoned the water supply for millions of people with cancer-causing benzene, forced officials to be more accountable.

A SENSITIVE SUBJECT ABROAD:

-- China says it has just as much right to develop its economy as rich nations, pointing out that they also polluted their environments to grow. But adding to tensions, environmental economists calculate the planet's finite resources mean China's huge population cannot achieve a US-style lifestyle.

-- In early 2007, China set up a national body on global climate change and in June it unveiled a plan for coping with global warming. But it also says rich countries are mainly to blame for greenhouse pollution to date.