The government has approved a $36-million protection scheme for the Dunhuang Mogao Grottoes, a World Heritage Site in Gansu province.The plan, approved by the National Development and Reform Commission, includes the construction of a digital display hall that can accommodate 800 visitors and facilities for consolidation, erosion prevention, security and visitor services, the Gansu provincial cultural heritage bureau said.Around 70 percent of the money will come from the central government and the rest from the province.The 1,600-year-old Mogao Grottoes boast more than 2,000 colored sculptures and 45,000 sq m of frescoes.The site was given World Heritage status in 1987.Wang Xudong, vice-president of the Dunhuang Academy, which protects and researches the grottoes, said: "The new facilities are designed to reduce the amount of time visitors spend inside the grottoes."Experts have said the vapors and carbon dioxide exhaled by visitors cause damage to the frescoes and sculptures.About 1,000 years ago, during the Sui and Tang dynasties, Dunhuang was a major trade hub on the Silk Road. It also became an important religious center. The sculptures and murals found in the grottoes have Buddhist, Islamic and Tibetan influences.About 550,000 domestic and overseas tourists visited the site last year, up from about 200,000 in 1998.The small grottoes are often packed with visitors and that poses a severe threat to the preservation of the frescoes and sculptures," Wang said.