[state Forestry and Grass Administration: a net reduction of 50,000 square kilometers of desertified land in China compared with 2009] the national home commemoration of the 29th World Day to Combat Desertification and drought was held in Yulin, Shaanxi Province on June 17. According to the event, China's desertification and land desertification continued to be "double reduced", with a net reduction of 50, 000 square kilometers of desertified land and 43300 square kilometers of desertified land compared with 2009. Forest and grass vegetation in sandy areas in China has improved significantly. Compared with 2009, the average vegetation coverage in sandy areas has increased by 2.6%. Over the past 20 years, the comprehensive vegetation coverage of forest and grass in the Beijing-Tianjin wind and sand source control project area has increased from 39.8% to 45.5%, and the forest coverage in the "three North" project area has increased from 5.05% in 1978 to 13.84%. The key management area has achieved a historic change from "sand advance and human retreat" to "green advance and sand retreat".