Equipment to monitor the origin and direction of sandstorms has been put into use in　six cities and counties in north China's Inner Mongolia　Autonomous Region，according to the local Environmental Protection Bureau。　
　　
Statistics showed Mongolia has been one of the principal　sources of sandstorms across the country in the past half　century，especially since 1993。 In 1999 alone over 60　sandstorms hit the region。　
　　
In order to monitor and control the sandstorms，11 ground　stations using advanced lidar technology have been established　by the local environmental protection departments。　
　　
The lidar systems would be mainly used to observe and　monitor the origin，direction and sedimentation of the　sandstorms，to helpthe local authorities take measures，said　Li Yawei，director of the Science and Technology Monitoring　Office under the Environmental Protection Bureau。　
　　
This monitoring system was considered one of the most effective means to observe the space distribution of　particulate matter in the air。　　　
　　
(Source: Xinhuanet 2003-12-19)