Changes of natural elements and maintaining of water conservation function in northwestern Hebei Province

Northwest Hebei has an irreplaceable ecological position in the coordinated development of Beijing, Tianjin and Hebei. Zhangjiakou City as the main part of the northwestern Hebei is a important barrier for maintaining the ecological security of the Beijing-Tianjin urban agglomeration and the upper and middle reaches of the Yongding River. This paper briefly introduces the background and related research results about the natural elements changes and water conservation function improvement in northwestern Hebei. Papers in the special journal issue focus on the development and utilization of water resources, water environment quality, water conservation function and its influencing factors. These findings will help to promote the rational use of water resource, improve the water conservation function and achieve green development.