Yangma Island

Yangma Island

Yangma Island, Mouping District, Yantai City, Shandong Province. It is located 9 kilometers north of Muping District, covering an area of 13.52 square kilometers. Yangma Island, also known as xiangdao, is named after the legend that Emperor Qinshihuang raised horses here during his East tour. Yangma island is not only the northern barrier of Muping port, but also the fishery level area of Muping District.

Yangma island is known as "Oriental Hawaii" for its beautiful mountains and sea and pleasant climate. Tourism development began in the 1980s. The island has many scenic spots such as racecourse and bathing beach, and more than 40 special and public convalescent reception facilities. It is a comprehensive tourist resort integrating sports, entertainment and seaside leisure. By 2008, it is a national AAAA scenic spot in China.

The origin of the name

The name of Yangma island has changed many times in history. It is said that Ju people were exiled here during the Warring States period, because they were named Ju Island, and because there was a small island in the east of the island, which looked like a giant elephant bathing in water, it was also called Xiang island.

There are two legends about the origin of the name "Yangma island". First, in the autumn of 219 BC, the first emperor of Qin toured the East and moved eastward through the Zhifu coast. One day at noon, people and horses came to the opposite side of Ju Island, only to feel sleepy. Suddenly, a gust of wind sent bursts of fragrance, neighing horse. When people looked around, they saw the green mountains, green vegetation and a group of horses playing on the island. Qin Shihuang couldn't help praising: "what a treasure island for raising horses!" So it was called "Royal Horse Island". He also ordered to send horses to all parts of the island to train horses for the Royal use. Later, the people were dissatisfied with the rule of Qin Shihuang, so they removed the word "Royal" and called it Yangma island.

Second, in the early Ming Dynasty, Japanese pirates harassed coastal residents. In order to avoid Japan, a large number of residents of Ju Island moved inland, and the land was idle for a while. Because of the fertile soil, the Japanese soldiers used this place to raise horses, thus leaving the name of Horse Island.

Location context

Yangma island is 1.5km away from the nearest land in Muping District, Yantai City, Shandong Province. It is located at 37 ° 28 ′ 00 ″ N and 121 ° 37 ′ 00 ″ E. The island is 7 kilometers long from east to west and 1.5 kilometers wide from north to south, with a total area of 13.52 square kilometers. The coastline of the island is 17.23 km long.

Geology and geomorphology

Stratigraphically, Yangma island is a Metamorphic Rock Island dominated by marble.

In the coastal area of Yangma Island, there are Cenozoic Quaternary strata, alluvial marine deposits. Its thickness varies from place to place, generally around 25 meters. The lithology from top to bottom is as follows: one is gravel. The sand is mainly composed of quartz and feldspar, light yellow and black minerals, with different particle sizes and good roundness; the gravel is mainly composed of gneiss, with a diameter of 1-10 cm, good roundness and a thickness of 11 m; the second is muddy clayey sand, which is grayish brown and grayish black, and contains more fine silt and humus, with poor viscoplasticity. This part of the strata is characterized by the development of carbonate rocks with complex lithology, containing a large amount of graphite and hosting metasomatic iron ore.

In terms of geological structure, Yangma island is located in the West Wing of Rushan Weihai anticline. The axis of the anticline is from Rushan Shitai to northeast, passing through the main peak of Kunyu Mountain, Wendeng Wangtuan and Yangting in Huancui District of Weihai, and then to Tiancun of Huancui District, with the axis of northeast. The first member of the second formation of Jiaodong Group is the core, and the second member is the two wings. Due to the influence of many magmatic activities, the fold morphology has been seriously damaged. Yangmadao kongtongdao fault zone is a NW trending tension torsion fault, which is distributed in the outer sea of Muping and similar to Penglai Weihai fault zone which also passes through the outer sea of Muping. The fault is large in scale, about 100 km long and 5-50 m wide.

Coastal topography. The beach coast of Yangma island is sandy, the front coast of Yangma island is muddy, and the back coast of Yangma island is gravel. The results show that the anti erosion ability of the bedrock in the coastal promontory is strong, and the speed of sea erosion retreat is slow; the loose sediment in the southern Bay is mainly the erosion material of the seabed bedrock, followed by the mud and sand carried by the river. The sedimentation rate of mud and sand in the bay is high, and there are long, narrow and intermittent sand mouths in the South and both sides of the bay. In 1979, after the East and West Long dikes of Yangma Island were completed, a long and narrow beach plain was formed along the East long dikes.

Yangma Island, a mountain range across the east-west, long and narrow terrain, northeast southwest. The northern part of the island is steep and rocky, while the southern part is gentle and Sandy. The landform is dominated by hills, which are connected by more than 10 hills. The highest point is xidashan, which is 108.4 meters above sea level. The island land landform types include bedrock slope and accumulation slope, and the bottom material mainly includes reef, gravel, coarse sand, medium sand, argillaceous silt and silty mud, which is suitable for the habitat and reproduction of a variety of marine organisms.

Sea area around the island

Yangma island is located in the north of the Yellow Sea. It is separated from the inland of Muping District in the south by Muping Bay. The water area is narrow. The nearest place is only more than 1 km. It is adjacent to the North Yellow Sea in the north.

Marine geomorphology

Muping harbor is located between moushan and ximiaojiang of Yangma island. The mouth of the Bay faces north. The bay is 1 km long from east to west and 0.5 km wide from north to south, covering an area of 0.5 square kilometers. The water depth is - 4m to - 6m. Because of the influence of Yangma Island levee, there is more silt at the entrance. Muping port is located on the South Bank of the harbor, with a general cargo wharf and a special chemical wharf; Yangma Island fishing wharf is located on the North Bank of the harbor.

Hulutou Bay, located in the south of sunjiatuan village, Yangma Island, is 0.5 km long from east to west and 0.5 km wide from north to south. The mouth of the Bay faces north, the water depth is quiet, the deepest is - 6 meters, and the bottom material is mostly sand and gravel, which is a good shelter. Due to the influence of the long dike connecting the islands, there is a lot of silt at the entrance, and the Bay moves about 0.5 km inward. It used to be a fishing port, but it has been abandoned.

Marine hydrology

sea wave. The main wave type in Yangma island is wind wave, with the frequency of 79% and swell frequency of 21%. The seasonal variation of wind wave frequency is obvious, most of which occurs in winter and most in December. Wave direction characteristics: in winter, there are more northerly and northwesterly winds, and northward waves are dominant along the coast with a frequency of 22%, followed by Northwest waves and northeast waves with a frequency of 18%. In spring, the wind direction along the coast is unstable, and there are still more northward waves. In summer, the wave direction is scattered, and the total frequency of southward wave is less than 25%. Distribution of wave height: in winter, under the attack of cold wave and strong wind, there are many big waves and big waves in the north direction. The maximum wave height is 7.28 meters in January and 6.6 meters in February. The wave height is smaller in summer, and the highest is 0.58M in June. In autumn, the distribution of coastal wave height is similar to that in spring.

tide. The tidal type of Yangma island is irregular semidiurnal tide. The diurnal tide in spring and summer is greater than that in night, and vice versa. The rising tide is the West current and the falling tide is the southeast current. It is a "revolving flow" rotating clockwise. The duration of high tide is longer than that of low tide. The average high tide level of spring tide is 2.07M, and that of neap tide is 1.46M. The mean low water level of neap tide is 0.81M. Due to the influence of Yangma Island trend (northeast to southwest), the opposite flow direction often appears. In addition, at the end of 1970s, the ten mile long dike of Qianhai in Yangma island was built, which made the west end of Qianhai flow southeast at high tide and northwest at low tide; the east end of Qianhai flow southeast at high tide and northeast at low tide. The average annual tidal range is 160-288mm.

Intertidal sediments. The bedrock outcropped along the coast of Yangma island is mostly Lower Proterozoic middle deep regional metamorphic rocks. Its lithology is mainly mixed granite. The stratum is the second member of Lower Proterozoic Jiaodong Group. The lithology is mainly gneiss, granulite and amphibolite. In some headlands, metamorphic granites with strong erosion resistance are exposed. There are obvious differences between the headland and the top of the beach.

Intertidal water quality. In 1990, the pH value of sea water in Yangma island was 7.2-8.2, and the contents of nitrite nitrogen, cyanide, arsenic, iron and chromium were small. The measured value of nitrite nitrogen was 0.018 in September, and the measured value of dissolved oxygen was 7.1-7.84 in Qianhai and Houhai of Yangma Island, which met the fishery water standard. The oxygen consumption in Houhai and Qianhai of Yangma island in May is in line with the requirements, and it is slightly higher in September. The sulfide is between 0.02 and 0.24, which basically meets the standard. The content of volatile phenol in the sea before and after Yangma island was zero.

climatic conditions

Yangma island is located in the middle latitude, belonging to the north temperate monsoon continental climate, with a continental degree of 57.4%. Due to marine regulation, it shows the characteristics of marine climate, such as cold spring, cool summer, warm autumn and winter, small temperature difference between day and night, long frost free period, strong wind and high humidity. The advance and retreat of monsoon and the change of four seasons are obvious.

There is a mirage in Yangma island. At 9:30 on September 26, 1990, a large area of mirage gradually appeared over the northeast of Yangma island in Muping County from northwest to Southeast, lasting about half an hour.

hydrologic condition

The island is short of water, no river.

The groundwater is karst fissure water, which is mainly distributed in the exposed area of metamorphic rocks in Yangma island. The aquifer is medium thick marble and feldspar quartzite. It belongs to calcium chloride water group, with pH value between 6.4 and 6.7, total hardness between 3.92 and 19.9 mg equivalent / L, oxygen consumption between 1.8 and 3.4 mg / L, and mineralization between 0.2 and 1.0 g / L.

Mineral resources

Limestone, distributed in the hills of Yangma Island, has been mined for generations, 198

Chinese PinYin : Yang Ma Dao