Beijing, April 9 (Youth.cn) - On April 7th, 2024, in the vast selenium-rich soil farmlands of Shuangqiao Village, Qingquan Town, Shandan County, Zhangye City, Gansu Province, farmers were utilizing sowing machinery integrated with seeding, fertilizing, film covering, and drip irrigation pipeline laying, guided by tractor autonomous driving systems powered by Beidou navigation technology, to sow selenium-enriched spring wheat. Photo/ VCG