The natural resources of the South China coastal zone are as diverse as its landscape. Abundant surface runoff is enriching to coastal biodiversity. As a sea-land transit area, the interactions between multiple factors in the surrounding environment make the area more sensitive to natural changes and human activities. Shenzhen Bay is one of the largest bays in the South China coastal zone. It is located between Shenzhen and Hong Kong, which are the two economic centers of the Guangdong–Hong Kong–Macao Greater Bay Area (GBA). Eight rivers, including the Fengtang River, flow into Shenzhen Bay. Because of population growth, urbanization, beach reclamation, tidal flat reclamation, and sewage discharge in the early development of Shenzhen City, the coastal zone has experienced an accelerated series of ecological problems. These problems include the serious pollution of the river water, habitat degradation, and the destruction of natural vegetation, resulting in a dramatic reduction in regional biodiversity. Therefore, Shenzhen City has conducted a comprehensive ecological management and restoration plan in the Shenzhen Bay since 2007. The implemented restoration plan improved water pollution management and ecological restoration methods to achieve the core strategy of enhanced water purification and rebuilding a healthy estuary ecosystem. During this progress, Professor Hai Ren (South China Botanical Garden) led the Fengtang River ecological restoration research subject which is in the National Science and Technology Support Program, and the Shenzhen Bay ecological restoration research subject which is funded by the Shenzhen Government. This research supported an ecologically sound build of Shenzhen Bay.

Under the leadership of Professor Hai Ren, a research group composed of a Ph.D. student Ke Liu (South China Botanical Garden), senior engineer Hualin Xu (Futian National Nature Reserve Administration Bureau of Guangdong), Tianzhu Ning (CSCEC Aecom Consultants Co., Ltd Shenzhen Branch) and others assessed pollution control and ecological restoration in Fengtang river. The results show a substantial improvement of the water quality after conducting the treatment of sewage water from the established rain and sewage flow diversion systems that directed the flow through the constructed wetland, and then through a natural wetland, a restored natural embankment, and finally through mangrove communities. With improved water quality and restored habitat, the biodiversity increased in a stepped process and the richness and abundance of alien invasive plants were significantly reduced. The assessment indicates that the ecological restoration approaches of coastal cities and estuary increase the biodiversity. This precedent in Shenzhen Bay provides a fitting ecological restoration and an ecosystem management model for the Guangdong–Hong Kong–Macao Greater Bay Area (GBA).

The results were recently published in Ecosystem Health and Sustainability, titled “Environmental remediation promotes the restoration of biodiversity in the Shenzhen Bay Estuary, South China”, Article link：

https://www.tandfonline.com/doi/full/10.1080/20964129.2022.2026250