Xuwen Coral Reef Nature Reserve

The coral reef of Xuwen was formed about 10 thousand years ago. It is the only modern coral reef developed and preserved along the Chinese mainland. It is also the largest natural resource with the largest concentration and the best preserved coral reef in China. When you come to Xuwen, you can take a private boat, look down from an airship or dive to visit the coral reef. Looking deep into the sea, you will see a vibrant undersea Park, colorful coral jungle, colorful schools of fish, dazzling shellfish and dense seaweed. The midday sunlight seeps into the boundless blue water, and the whole wave light is sparkling, like a plate of crystal falling into the sea.

Xuwen Coral Reef Nature Reserve

Xuwen Coral Reef Nature Reserve, located in Jiaowei Township and Xilian Town, west of Xuwen County, Zhanjiang City, Guangdong Province, covers an area of about 109 square kilometers. It is the largest contiguous area, the most concentrated species and the best preserved coral reef natural resources in China. In 1999, the people's Government of Xuwen County established a nature reserve to strengthen the protection of coral reef natural resources in the area; in 2002, it was upgraded to a municipal nature reserve with the approval of Zhanjiang Municipal People's government. Through scientific research and investigation, 49 species of coral in Xuwen Coral Reef Nature Reserve have been identified, including 2 orders, 17 families and 2 species to be identified.

brief introduction

Xuwen Coral Reef Nature Reserve is located in the southwest of Leizhou Peninsula, Guangdong Province, in Xuwen County, Zhanjiang City. It is distributed in the Western sea area of Jiaowei, Maichen and Xilian, with latitude of 20 ° 10 ′ 36 ″ - 20 ° 27 ′ 00 ″ N and longitude of 109 ° 50 ′ 12 ″ - 109 ° 56 ′ 24 ″ E. The total area of the reserve is 14378.5 hectares. In August 1999, the people's Government of Xuwen County approved the establishment of a coral reef nature reserve at the county level; in July 2002, the people's Government of Zhanjiang City approved the upgrading to a municipal Coral Reef Nature Reserve; in June 2003, the people's Government of Guangdong Province approved the upgrading to a provincial Coral Reef Nature Reserve; in April 2007, the State Council approved the upgrading to a national nature reserve.

Xuwen Coral Reef is the only modern coral reef developed and preserved along the coast of mainland China. Coral reef area is rich in fishery resources, with many species and rich economic biological resources. The coral reef area is 10867 hectares, including about 6000 hectares of dense areas. There are 82 species of Anthozoa in 19 families, 3 orders in Cnidaria, including 27 species in 7 families of soft corals, 1 species in 1 genus and 1 family of sea anemones, and 54 species in 11 families of lithocorals. All of these 54 species of lithocorals are the national second class protected animals and listed in the cites Convention on international trade in endangered species of Wild Fauna and flora.

Historical evolution

The historical evolution of Xuwen Coral Reef Nature Reserve.

The coral reef of Xuwen was formed about 10 thousand years ago. It is the only modern coral reef developed and preserved along the coast of Chinese mainland.

Coral reef area is rich in fishery resources, with many species and rich economic biological resources. The coral reef area is up to 163000 mu, of which the dense area is about 90000 mu.

In August 1999, Xuwen County People's Government approved the establishment of a county-level Coral Reef Nature Reserve; in July 2002, Zhanjiang City People's Government approved the upgrading to a municipal Coral Reef Nature Reserve; in June 2003, Guangdong Provincial People's Government approved the upgrading to a provincial Coral Reef Nature Reserve; in April 2007, the State Council approved the upgrading to a national nature reserve

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General situation

According to two comprehensive scientific surveys conducted by Zhanjiang Ocean University of Guangdong Province in 2001 and Nanhai Institute of Oceanography, Chinese Academy of Sciences in 2004, 65 species of Anthozoa, 18 families and 3 orders of Cnidaria, have been found in Xuwen Coral Reef Nature Reserve.

Corals live in the shallow water of tropical ocean at low latitude. The dead reef building corals are cemented with some shells and calcareous algae to form large porous calcareous solids, which are as strong as reefs, so they are called coral reefs. Apart from the extensive development of coral reefs in Xisha, China, Sha and Spratly Islands in China, it is rare to find such a large reef in Xuwen.

Coral reefs provide a good habitat for tropical marine organisms, and play a great role in protecting marine biological resources and ecological environment and preventing coastal erosion. Coral is widely used in paleogeomorphology, paleogeography and paleoclimate research. Coral can be developed into a variety of drugs, used for bone repair, made into anti ultraviolet shading agent, drugs for the treatment of cardiovascular system, anticancer drugs, artificial bone and so on. At present, it is found that the sea anemones distributed in the reserve can extract drugs 10000 times more toxic than cyanide for cancer treatment, which is worth ten thousand gold per gram. With the development of new molecular technology for isolation and identification of complex organic compounds, the application of coral will be more and more in-depth, and the research value of coral will be further reflected. Coral Reef Nature Reserve is a potential drug resource.

Geography and climate

1. Geology and geomorphology

Jiaowei Township and Xilian town near the reserve are coastal areas, facing the sea on three sides. The terrain is low and flat, slightly higher in the north and lower in the south. The geology is mostly sandy soil and sandy soil. The coast and intertidal zone of the reserve are basically sandy beaches and reefs, mainly composed of coastal shallow marine sandy argillaceous clastic rocks and lacustrine gypsum salt bearing clastic rocks. The lithological characteristics are mainly light gray green siltstone, brown red mudstone and gray black basalt. There are more corals growing on gray black basalt, and they are also more luxuriant.

2. Climate

The Nature Reserve belongs to the tropical monsoon climate zone, with sufficient sunshine, high annual average temperature and unobvious four seasons; abundant rainfall, large interannual change rate; the same season of rain and heat, and distinct dry and wet seasons.

3. Tide and tide

Tide: the tidal phenomenon in Xuwen coastal zone is mainly formed after the Pacific tide wave enters the South China Sea. Xuwen County is opposite to Hainan Island from north to south. The Qiongzhou Strait between Xuwen County and Hainan Island runs from east to west, slightly like a strip-shaped inland channel. The East and West outlets are respectively connected with the qizhouyang and Beibu Gulf. With the influence of the southeast, southwest and northeast monsoon and the uneven terrain at the bottom of the Strait gully every year, irregular mixed tides are formed. The reserve is mainly controlled by the irregular diurnal tide in Beibu Gulf.

Tidal current: the tidal current in the reserve is unevenly distributed, and the velocity in the sea area connected with Qiongzhou Strait in the South and the west of shuiweijiao is relatively high, while in the sea area to the west of Dongchang in the Bay, the velocity is very low or even not obvious.

4. Surface circulation

The surface circulation in the reserve is mainly controlled by the surface circulation in Beibu Gulf. In winter, it is strongly influenced by the surface circulation in the west direction of Qiongzhou Strait, and the circulation direction is mainly in the north and northwest directions. In summer, it is strongly influenced by the southwest monsoon and the eastward circulation of Qiongzhou Strait, and the circulation direction is mainly southeast and south.

5. Water temperature distribution and seasonal variation

The lowest water temperature in the reserve is about 18 ℃ in January every year. The highest water temperature occurs in July, about 30.5 ℃, and the annual average water temperature is about 26 ℃.

6. Disastrous weather

It is mainly affected by tropical cyclone, typhoon, hail, tornado and cold wave.

Introduction to coral

From a biological point of view, corals are animals. Corals are formed by the aggregation of numerous tiny corals, which are low-grade marine animals. Most of the stone corals live in groups with a large number of individuals, and the individual is very small, often only a few millimeters. The shape of a coral is like a flower, with a ring of tentacles at the top, like petals, and a cylindrical column, like the ovary of a flower. Corals absorb calcium carbonate that dissolves in seawater and use it to make their own bones. The white corals we usually see are actually the skeletons left behind by the dead corals, and the real living corals are the tender "little flowers" on them. In the sea, the living corals are colorful, with red, green, yellow and gray, interlacing with each other. During the day, most corals only expose pigmented tissues to absorb sunlight, allowing symbiotic algae inside the body to carry out photosynthesis; at night, they stretch out the corals, and the flower like corals become tools of predation.

In the coral tissue, there is a kind of unicellular algae called "zooxanthophyta", which forms a symbiotic relationship. The colorful colors of corals are formed by these zooxanthellae symbiotic in the coral muscle tissue. The main nutrients of Chrysophyta are nitrogen, phosphorus and potassium. Algae in sunlight photosynthesis, absorption of carbon dioxide, these nutrients can be converted into organic matter, and in the process of metabolism release oxygen. Corals, on the contrary, need to absorb oxygen and emit carbon dioxide, as well as waste containing nitrogen and phosphorus. Therefore, the two symbiotic, the yellow algae can use the coral excreta and carbon dioxide gas, and coral use the yellow algae metabolism of oxygen, accelerate their own growth and development. However, non reef building corals without the symbiosis of zooxanthophyta can not build reefs because of their slow growth rate of calcification. However, these close symbiotic creatures can only survive together, but can not share hardships.

Chinese PinYin : Xu Wen Shan Hu Jiao Zi Ran Bao Hu Qu