The Shenzhen Bay separates Hong Kong from the city of Shenzhen in Mainland China. The Bay is a political and cultural border between the cities, but creates an ecological continuity between them. The inner Bay’s costlines are covered by mangroves. Mangroves are intertidal ecosystems with tropical and subtropical trees and shrubs, and provide a wide range of ecosystem services. They belong to the most productive and also the most threatened ecosystems in the world.
Mangrove habitats have made the Shenzhen Bay an internationally important area for migratory birds, which use the area for a wintering site and stop-over point on East Asian-Australasian flyway. This global flyway is used by 50 million migratory waterbirds coming from the breeding grounds in Mongolia, Siberia and northern China. The Bay hosts tens of thousands migratory birds every year, and many of the bird species are globally threatened.
These were the background facts for our mangrove trips in the Shenzhen Bay area. The urban context is astonishing:
Shenzhen and Hong Kong are two urban clusters within the Pearl River Delta, which is said to be the biggest and most rapidly expanded urban area in human history
Shenzhen started to grow from some small fishing villages in 1980 to its current population of more than 10 million, perhaps even 19 million people
The cities face big environmental challenges, such as water pollution and habitat loss. Both cities have made efforts to safeguard the Shenzhen Bay mangrove ecosystem. Mai Po Nature Reserve (380 hectares) was established at Hong Kong side of the bay in 1976 and later managed under the policies of the Ramsar Convention on Wetlands (https://www.wwf.org.hk/en/whatwedo/water_wetlands/mai_po_nature_reserve/).
At the other side of the bay in Shenzhen, Futian Mangrove Nature Reserve (368 hectares) was conserved in 1984, following China’s National Nature Reserve System. These two conservation areas have been successful in increasing the areal extent of mangroves (Jia et al. 2016). In both areas, the conservation is roughly based on three zones: a core, a buffer and a zone for experimentation and research.
Other mangrove sites still exist in both cities, but they are scattered. The problem is that many of them are shrinking due to urbanization and infrastructure development particularly in Shenzhen. In Hong Kong, the town planning board has followed the principle of no net loss of wetlands since 1999. Recently, the amenity values of mangroves have been appreciated and utilized in city renovation projects and urban design in Shenzhen. In our field trip, we could see a massive building project at the northern side of Shenzhen Bay. The aim of this landscaping project was to halt an aggressive 30-year landfill at the coastline and integrate recreation, urban renovation and mangrove conservation (http://www.swagroup.com/projects/shenzhen-bay/).
We made two other field trips to take a closer look at mangrove wetlands. In Shenzhen, we could not enter the Futian reserve but had access to the OCT Wetland (see more here), which is a smaller one and categorized as a wetland park. The park was created by the city and companies as a part of a brownfield project. In this wetland park connected to the Shenzhen Bay system, we could walk into a mangrove planting area; restoration by planting and replanting is an important measure to conserve mangrove wetlands. In Hong Kong, we visited Wetland Park (see more here), which is an open-access wetland area next to Mai Po Nature Reserve and serves as a buffer between it and the built city.
The picture above is a view of the mangrove park in Shenzhen
The picture above is a view of the mangrove park in Hong Kong
The visits in these two wetland parks guaranteed our success in seeing mangroves, masses of birds, hundreds of plant species and taking photos. Using nature trails, board walks and bird-watching hides, we had a memorable experience to feel the diversity of subtropic nature and its various stages of development. We spotted black-faced spoonbills, which exist in both parks. It is an endangered bird species and the main symbol of nature conservation in the region. It breeds in North Korea, and even a quarter of its world population can be found in Mai Po Nature Reserve during migration.
Both of these wetland parks follow the idea that mass tourism can be allowed without compromising the conservation values, if the access of visitors is strictly coordinated. This has required heavy investment in structures, design, personnel, and big visitor centers with exhibition galleries. The wetland parks also want to enforce habitat conservation and ecological monitoring, develop education and research programs, school visits and guided tours. The figures are high in these parks. In 2016, Wetland Park attracted 490 000 visitors, including over 51 000 overseas tourists, and arranged 4 100 guided tours. This kind of multi-task conservation of ecosystem services with massive crowds of people requires that stakeholder collaboration has to be developed accordingly.
Visitors can get close to birds in the wetland parks (Hong Kong)
The infrastructure in these parks is created to support different stakeholders interests (Hong Kong)
Mangrove ecologist, professor Nora F. Y. Tam from the City University of Hong Kong has studied the use and conservation of mangroves across both sides of the Bay. She has categorized stakeholders into four groups (Tam 2004, 170):
Primary stakeholders: local communities whose livelihoods are directly dependent on mangrove resources, such as fishermen, paddy farmers and wood makers
Key stakeholders: government officials, developers and resource economists whose actions directly affect decision-making
Secondary stakeholders: tourists and traders who have an interest in the mangroves but without any direct involvement
Ecologists and conservationists who have a strong view to preserve the mangroves
The list is helpful for considering the human-natural problematics of mangrove ecosystems. To update and contextualize the list, we provide some additions to it from our field trips, document data, and our conversations with local people and conference participants:
Designers, consultants and other experts who apply global models in urban regeneration and ecological restoration
Local and global NGOs, such as Shenzhen Bird Watching Society and WWF Hong Kong
Private companies who take responsible roles in conservation activities
State-owned companies operating as a commercial enterprise, such as the OCT Group in Shenzhen
Charity organizations that interlink entrepreneurs and stakeholders in conservation activities, such as Shenzhen Mangrove Wetlands Conservation Foundation
Citizens as volunteers in conservation activities
Potential brokers who are able to work across various departments in government, making conservation more efficient
Media stakeholders, bloggers, people interested in networking
Learners who are impressed by mangroves and produce creative ideas for collaborative conservation
A growing platform in Shenzhen. Growing local mangrove species, that will be later planted into the wetlands
We found that ’primary stakeholders’ in the original list are not totally disappeared. There are still fishponds and gei wais operating in traditional ways in Mai Po Nature Reserve. They are a central part of the history of this wetland area, enrich its biodiversity values and belong to its key habitats. Gei wai means a pond enclosed by bunds, and it has been long used in tidal coastal areas in Asia to produce shrimp, fish and oysters. We could see several ponds from a tower in Wetland Park.
Soon after returning back to Finland, we found news that the Shenzhen city government is planning to build China’s first mangrove museum in the city to promote mangrove conservation.
Jia, M., Liu, M., Wang, Z., Mao, D., Ren, C., & Cui, H. (2016) Evaluating the effectiveness of conservation on mangroves: A remote sensing-based comparison for two adjacent protected areas in Shenzhen and Hong Kong, China. Remote Sensing, 8(8), 627.
Tam, N. F. Y. (2004) Conservation and uses of mangroves in Hong Kong and Mainland China. In M. H. Wong (ed.) Wetlands ecosystems in Asia: function and management. London: Elsevier, pp. 161–182.