Xi-jie Chen, Li-qiong Jia, Ting Jia

Development and Research Center of China Geological Survey, Beijing 100037, China

1. Basic overview of China’s islands

The total length of China’s coastline is 32000 km,including 18000 km of mainland coastline and 14000 km of island coastline. There are more than 11000 islands in China,and the total area of islands accounts for about 0.8% of China’s land area. The number of islands in Zhejiang, Fujian,Guangdong, and Hainan ranks in the top four. Divided by region, the number of islands in the East China Sea accounted for about 59% of the total number of islands in China, the islands in South China Sea accounted for about 30%, and the islands in Bohai Sea and Yellow Sea accounted for about 11%. According to the distance from the shore, the number of islands less than 10 km away from the mainland accounted for about 57% of the total number of islands, 10-100 km away from the mainland accounted for about 39%, and more than 100 km away from the mainland accounted for about 4%. By the end of 2017, there were 7933 islands with names and landmark monuments in China.

2. Resources on the islands

2.1. Freshwater resources

The island’s fresh water supply mainly comes from water diversion from the mainland, water transport by ships or cars,and island wells, reservoirs, rainwater collection, and seawater desalination. There are 665 islands with fresh water supply, including 452 islands with residents and 213 islands without residents. There are 494 islands with reservoirs and 89 with water diversion from the mainland. Beginning in 2017, the construction and upgrading of seawater desalination projects will be implemented on about 100 islands, with a preliminary planned total scale of about 600000 t per day.

2.2. Vegetation coverage

In 2017, the total vegetation coverage of more than 10000 uninhabited islands under remote sensing monitoring was about 25181.5 hectares, and the vegetation coverage rate was about 52.0% (Fig. 1).

Fig. 1. The island vegetation in the Yacheng Bay of Ningde, Fujian Province in the East China Sea (Photo credit: Dr. Shi-pu Bi from Qingdao Institute of Marine Geology, China Geological Survey)

2.3. Animal and plant resources

The island and its surrounding waters are rich in animal and plant resources. By the end of 2017, 24 species and 86 species of national first- and second-level key protected wild animals were found on the island and its surrounding waters,and 5 and 32 species of national first- and second-level key protected wild plants were found.

2.4. Tourism resources

The island and its surrounding waters are rich in tourism resources. By the end of 2017, 1028 natural landscapes and 775 cultural landscapes have been confirmed on islands across China. 72 beaches of various types have been built and put into use. There are six 5A-level island-related tourist areas, 43 4A-level island-related tourist areas, and 25 3A-level island-related tourist areas. Island tourism has become a new hot spot for mass tourism.

3. Water quality of the sea area around the islands

3.1. Water quality of the sea area where the islands located

In 2017, the seawater quality of some islands in China was inferior to the fourth category, mainly located in Hangzhou Bay, the coast of Zhejiang, and the Pearl River estuary. In spring, 56.2% of the islands in which the water quality is in the first category accounted for 56.2%, and 25.2% were inferior to the fourth category; in autumn, 40.5% of the islands had the first category of water quality and 31.7% inferior to the fourth category.

In 2017, the degree of eutrophication in the sea area around the island has changed greatly. In spring, it accounted for 95.7%, of which: the number of islands with mild,moderate, and severe eutrophication accounted for 71.5%,14.3%, and 14.2%. In autumn, it accounted for 86.3%, of which: mild, moderate, and severe accounted for 68.4%,12.0%, and 19.6%, respectively.

3.2. Water quality of the sea area around the islands

In 2017, the water quality around the inhabited islands in spring, summer, autumn and winter is worse than the fourth category water quality by 45.2%, 36.5%, 52.8% and 48.7% respectively.

The main pollutants were inorganic nitrogen and phosphate etc. Among the islands in the reserve, the water quality of the surrounding sea areas in spring, summer,autumn, and winter have 27.9%, 11.1%, 24.2%, and 27.5% inferior to the fourth category, respectively. The main pollutants are inorganic nitrogen, phosphate and petroleum etc.

4. Island human settlements

4.1. Island power supply

By the end of 2017, a total of 801 islands across China had achieved power supply. There are 441 inhabited islands with power supply and 416 with 24-hour power supply; 360 uninhabited islands with power supply and 300 with 24-hour power supply. The power supply method is mainly from offisland power, supplemented by independent power generation, and some islands adopt a comprehensive power supply method that combines the two methods.

4.2. Island transportation

By the end of 2017, 1363 piers have been built on islands across China. Among them, there are 770 passenger and cargo wharves, 501 fishing ports and 92 official wharves. The total length of grade highways on the island is 6475 km. There are 12 airports, 8 submarine tunnels and 153 bridges on the island(Fig. 2). The travel conditions of island residents have gradually improved.

Fig. 2. The Changshan Liandao Bridge in the Bohai Sea connects the north and south islands, Shandong Province (Photo credit: Dr.Shi-pu Bi from Qingdao Institute of Marine Geology, China Geological Survey).

4.3. Island pollution prevention and control

By the end of 2017, 168 sewage treatment plants and 73 garbage treatment plants have been built on the islands in China; they have treated 38.53×106t of sewage and 1.43×106t of garbage. The island environment has been greatly improved.

4.4. Island air quality

In 2017, the number of days with good air quality in the counties (cities, districts) where the islands are located was an average of 305 days, which was higher than the average in the mainland. The air quality on the islands was generally good.

4.5. Island disaster prevention and mitigation

In 2017, China’s islands suffered 16 typhoons such as "Nesat", "Haitang", and "Hato", and 34 catastrophic waves.There are 6183 times red tides and green tides occurred in the surrounding waters of the islands. There are 254 safe havens built and put into use on the island, with 870 km of seawalls and 733 km of breakwaters. Disaster prevention and mitigation capabilities have been continuously improved.

5. Island protection and restoration

In 2017, there were more than 10000 uninhabited islands under remote sensing monitoring, with a natural coastline of about 5948 km, of which the sandy coastline was about 312 km. The retention rate of natural shorelines is about 93.5%.

5.1. Construction of various reserves involving islands

By the end of 2017, China had established 194 various types of reserves involving islands. Among them, there are 70 national-level reserves, 58 provincial-level reserves, 30 municipal-level reserves, and 36 county-level reserves.According to the types of reserves, there are 88 nature reserves. Among them: 75 special reserves (including ocean parks), 13 aquatic germplasm resource reserves, seven wetland parks, two geological parks, and nine other types of reserves.

5.2. Island ecological restoration

By the end of 2017, the central government+local government+enterprises have invested a total of approximately 9.1×109RMB in 198 island ecological restoration and restoration projects. A total of about 336 hectares of islands were restored, about 70 hectares of vegetation were planted, about 3.3 hectares of mangroves were planted, about 39 km of island coastline was renovated,about 74 hectares of island beaches were restored, and nearly 30×106km3of silt around the island was dredged, and the total amount of garbage removed from islands and beaches is approximately 85000 km3. The comprehensive ecological index has increased substantially.

5.3. Island public facilities

By the end of 2017, there were 3494 public welfare facilities on China’s islands, including 1470 navigation aids,1334 surveying points, 347 meteorological observation facilities, 240 marine monitoring stations, 103 earthquake monitoring stations, and the number of other public welfare facilities has increased.

6. Economic development in China’ islands

6.1. Overall development

In 2017, the total permanent population of the 12 main island counties (cities, districts) at the end of the year was approximately 3.44×106; the total fiscal revenue was approximately 48.4×109RMB, and the total fiscal expenditure was approximately 64.3×109RMB; the total investment in fixed assets was approximately 239.9×109RMB; The total output value of marine industry is about 355.7×109RMB,decrease by 16.3% from 2016.

6.2. Marine industry

The marine industries of the 12 main island counties(cities, districts) are dominated by marine tourism, marine aquatic product processing, marine fisheries and marine shipbuilding, accounting for approximately 71.6% of the total marine industry output value in 2017. The total output value of the marine tourism industry is about 89.7×109RMB, and the annual number of tourists is about 98.36×106; the total output value of the marine aquatic product processing industry is about 63.9×109RMB; the total output value of the marine fishery industry is about 60.5×109RMB; the total output value of the marine shipbuilding industry is about 40.6×109RMB, decrease by 60.0% from 2016.

On September 21, 2017, the “China-Small Island States Ocean-related Ministerial Round Table” with the theme of“Blue Economy ·Ecological Islands” was held in Pingtan,Fujian. Representatives from 12 island countries on four continents participated in the roundtable meeting. The meeting adopted the “Pingtan Declaration”, which deepened the mutual understanding and communication between China and island countries. Strengthen cooperation in areas such as applications, and call for continuous strengthening of coordination and cooperation in the United Nations Sustainable Development Framework, APEC and other relevant international and regional organizations to jointly promote the sustainable development of the global ocean.

(Source: “Statistical Communiqué on China ’s Island Survey in 2017” issued by the Ministry of Natural Resources of the People’s Republic of China in July 2018)