XINING - China injected 1 billion yuan ($158.4 million) in 2011 to protect the natural environment of northwestern Sanjiangyuan, the headwaters of China's three major rivers.

The money was spent on afforestation projects and recovery of degraded grasslands in the area, Li Xiaonan, vice director of the Qinghai Sanjiangyuan Office, told Xinhua.

Sanjiangyuan, with an area of 150,000 square kilometers, is the headwaters of the Yangtze, Yellow, and Lancang rivers. The Lancang is also known as the Mekong, which originates from China and flows through Myanmar, Laos, Thailand, Cambodia and Vietnam.

The regional ecology significantly deteriorated in recent years due to global warming and excessive herding, before the government initiated a 7.5-billion-yuan program, which included the resettlement of 50,000 Tibetan herders in 2005.