Aerial photo taken on May 12, 2019 shows a boat sailing on Songhua Lake in Jilin City, northeast China's Jilin Province. As a province rich in ecological resources, Jilin has promoted the conservation of fertile soil, natural forest resources and water systems to lay a solid foundation for its sustainable development. Located at the intersection of Changbai Mountains and Songnen Plain, Jilin City, is an important water conserving area for the Songhua River basin. Many rivers and tributaries of the Songhua River, Lalin River and Mudanjiang River also run through the region. In recent years, the improved water quality of the Songhua River helps provide citizens in Jilin City with approaches to the nature, and boost tourism and city construction. The Beijing International Horticultural Exhibition kicked off its "Jilin Day" event on Thursday and will last until Saturday. (Xinhua/Xu Chang)