HOHHOT, March 11 (Xinhua) -- Inner Mongolia Autonomous Region, lying at the forefront of China's fight against desertification, has mobilized 76.6 million volunteers to plant trees over the past seven years, local authorities said Monday.

The campaign has planted 445 million trees to guard north China against sandstorms and desert encroachment in the period, the autonomous region's forestry and grassland bureau said ahead of China's Arbor Day on March 12.

The bureau said Inner Mongolia has since 2012 beefed up its tree-planting efforts with measures such as assigning afforestation targets to local officials and encouraging volunteer participation.

The autonomous region has planted over 1.7 billion trees on about 400,000 hectares of lands since 1981, when China started to encourage the public to plant trees.

Inner Mongolia is home to several large deserts such as Badain Jaran, Tengger, Ulan Buh and Kubuqi. Its success in taming desertification in recent decades has been credited to the decrease of sandstorms in northern China.