Presenter
Miss. Shuang Shuang LI, Yongding River Investment CO., LTD
Co-author(s)
Ms. JIAO Xiu QI, Yongding River Investment CO., LTD
Mr. Wei HE, Yongding River Investment CO., LTD
Sub-theme
4. Supporting Aquatic Ecosystem Health and Functions
Topic
4-4. Ecological restoration of degraded rivers and lakes
Body
(a)Yongding River is the mother river of Beijing, which is an important water conservation area, ecological barrier and ecological corridor of Beijing, Tianjin, Hebei and Shanxi. And it has an important strategic position. (b)Since the 1980s, problems such as over-exploitation of water resources, the dry flow of the river, and the severe degradation of the ecosystem in the Yongding River have been the most. In order to solve these problems. Since 2018, the trans-provincial River basin Governance Investment Company promoted by the top-level design was established, which is the first in China to base on the whole river basin, adhere to unified planning, unified governance, unified scheduling and unified management, and focus on improving the stability, sustainability and diversity of the ecosystem of Yongding River Basin. The "Yongding River" model of river basin governance has been preliminatively established, and remarkable governance results have been achieved. (c)This paper collected the measured runoff of three sections(such as Sanjiadian,) during 1956-2020, the historical remote sensing image data and the measured groundwater level data over the years and other basic data, and analyzed the governance effectiveness of six multi-dimensional indicators by using a variety of methods, such as cumulative anomaly curve method, GIS spatial analysis method and data comparison method. (d)The main conclusions are as follows: (1) Vertically, the normal ecological water supplement has broken the situation that Yongding River has been cut off for many years. In 2022, the annual runoff of Sanjiadian section is 369 million m3, and the annual runoff of the river has recovered to the average level of 1980s. With the change of underlying surface, the overall flow velocity increases after the full flow of the river. (2) Horizontally, the shape of river section is reshaped, which basically guarantees flood safety in flood season; River meandering has returned to the average level of the 1970s; (3) Vertically, restore the underlying surface of the river channel, replenish groundwater, and reduce the infiltration of surface water; The construction of river ecological corridor, promote the restoration of river habitat, vertical biodiversity significantly increased. And finally through comparative analysis of the multi-dimensional effects before and after the governance, it is clear that the watershed governance model of "Yongding River" is feasible, in order to provide reference for other small watershed ecological governance.