There are 5 soil types, 13 subtypes and 52 soil types in China. Red soil, distributed in hilly areas below 500 meters, covers an area of 69,333.33 hectares, accounting for 64% of the county's land area. Yellow soil, mainly distributed at the back of the ridge below 500 meters, covers an area of 293.33 hectares, mostly in Xizhou Town. Tidal soil, mainly distributed in coastal dry land, Qiantang of military camp, Yong 'antang of Jinxing, Tang Ying pond of Gaotang Formation, etc. , covering an area of 3266.67 hectares, accounting for 2.6% of the county's territory. Its parent material is modern marine sediments with deep soil layers. Saline soil that was once submerged by tidal water has a heavy salt content, mostly newly reclaimed pond fields, covering an area of 4866.67 hectares. Paddy soil, distributed in coastal plains and river valleys, is the main agricultural soil in the county, covering an area of 30,200 hectares, accounting for about 29% of the total soil area.
Hilly slope
* * * 72000 hectares. 7953.33 hectares of arable land, mainly distributed below 250 meters above sea level, with gentle slope, deep soil layer and good water conservancy conditions, is suitable for the growth of grain crops, fruits and tea. There are 50,000 hectares of sloping land suitable for forest, mainly distributed in hills and low mountains. It is suitable to build timber forest slopes of 30,666.67 hectares, firewood forest slopes of 20,000 hectares and grass slopes of 4,666.67 hectares for grazing cattle and sheep. Nearly 4667 hectares are difficult to be used in agriculture, forestry and animal husbandry.
littoral plain
The flat land with a relative height of < 5m and a slope of < 3 is 462 13.33 hectares, accounting for 33.36% of the total land area. A small part is a small plain deposited by the mainland. Most of them are coastal marine sedimentary plains reclaimed from beaches in past dynasties, with a total area of 3 1 533.33 hectares, of which block 10 is distributed in Xiangshan Port, Dongwan and Sanmen Bay.
The coastal plain in the north of Xiangshan Port, 2950 hectares in Xizhou Plain, 200 hectares in Huang Bi Ao Plain, 0/.450 hectares in Xian 'ao Plain and 0/.600 hectares in Zhuxi Plain are mainly rice.
Nanzhuang Plain, the eastern coastal plain, is 6300 hectares, which is the largest marine plain in the county and one of the main grain producing areas. Zang Qianping used to cover an area of 850 hectares, mainly producing rice.
The coastal plain of Nansanmenwan is 5,800 hectares of Dingshan Plain, which is a marine plain, second only to Nanzhuang Plain, with an average elevation of 3-5 meters. It is one of the main grain producing areas and the largest vegetable base and soybean producing area in the county. Venus Plain covers an area of 1.400 hectares, with an average elevation of 3-5 meters. Mainly produces rice, rich in cotton and citrus. Gaotang Plain, 1900 hectares, an ocean plain with an average elevation of 3-5 meters, mainly produces rice, cotton and citrus.
beach
There are 25 large and small beaches, 1 1 beach (stone beach). The beach area is 20526.67 hectares, and the suitable reclamation area is 6526.67 hectares.
Construction land, towns, villages and industrial and mining land are mainly distributed in the central city, Shipu, Western Zhou, Qiangtou, Hepu, Xianlong and Tang Ding, with a total area of 1 14 16.63 hectares. plant resources
Woody plants 9 1 family, 242 genera, 479 species, including 2 15 species of trees. Heptacodium miconioides, Fokienia hodginsii, Ginkgo biloba, Cupressus orientalis, Phoebe chekiangensis and Magnolia Tianmu are national protected plants. Osmanthus fragrans is a precious flower in Xiangshan history and was called by Song people. Herbs are mainly weeds, and there are abundant resources of herbs, medicinal materials and flowers.
Animal resources
There are about 14 families of wild mammals, about 33 families of birds, about 40 species of reptiles in 9 families, about 7 families of amphibians, mainly frogs, and more than 700 species of insects in 2 1 order 122 families. Freshwater fish 152 family, 22 genera, marine fish, 4 classes, 29 orders 152 family, 300 genera, 442 species. Total water resources
The total amount of water resources in the county is 930 million cubic meters, and the total amount of water resources per capita is about 20% lower than that of the whole province and the whole country, which is a water-deficient area. The runoff area in the west is 163 square kilometers, and the total annual runoff is143.54 million cubic meters. The central runoff area covers an area of 222 square kilometers and the annual runoff is 1.8 1.22 million cubic meters. The southern runoff area covers an area of 389 square kilometers and the annual runoff is 286.09 million cubic meters. The runoff area in the north covers an area of 248 square kilometers and the annual runoff is19.05 million cubic meters. Island runoff area, with an area of 154 square kilometers and an annual runoff of 76.47 million cubic meters.
riverbed
The total length of rivers in the county is 7 10/0km, and the density of river network is 0.6 1 km/km2. The drainage area of Datang Port is 134 square kilometers and the river length is 18 kilometers. Nandahe River basin covers an area of 82. 17 square kilometers, with a river length of 7.8 kilometers. Guanggang, with a drainage area of 52.5 square kilometers and a river length of 5.5 kilometers. The drainage area of Bai Dun Port is 49.9 1 km2, and the river length is 7.8km.. The basin of Shenxia Port covers an area of 40 square kilometers and the river is 4.2 kilometers long. Hepu River, with a drainage area of 4 1.3 square kilometers and a river length of 5 kilometers. Dachangxi, with a drainage area of 32 square kilometers and a river length of 3 kilometers.
reservoir
The total storage capacity is 65.438+0.37 billion cubic meters. There are 20 reservoirs with a storage capacity of more than 6.5438+0000 cubic meters, including 6 reservoirs with a storage capacity of more than 5 million cubic meters and 4 reservoirs with a storage capacity of more than 6.5438+0000 cubic meters. The total storage capacity of Datang Port Reservoir is 3 1.35 million cubic meters, Xikou Reservoir 1.25 million cubic meters, Cang 'ao Reservoir 1.65 million cubic meters and Gexizhang Reservoir 1.50 million cubic meters. aquatic product
Xiangshan is close to the three major fishing grounds of Damuyang, Maotouyang and Yushan, and its fishery development conditions are superior. It is a big fishing county. The main aquatic resources are yellow croaker, hairtail, squid, pomfret, dragon head fish, catfish, shrimp, crab, grouper, sea eel, kelp, laver, mud snail and so on.
chemistry of sea waters
Salinity rises and falls twice a year, and it rains and falls in May and June. During September ~ 165438+ 10, the Yangtze River flows southward and falls; After June, the warm current in Taiwan Province Province rose; After 1 1 month, the vertical mixing of seawater is strong and rises. The highest salinity in summer is 28. 13‰ in Xiangshan port, 25. 14‰ in Sanmen bay and 26.5 ‰ ~ 30.8 ‰ in Damuyang.
sea salt
Xiangshan salt production has a long history. Salt was made from seawater in the Tang Dynasty, and Yuquan Salt Field was set up in the Northern Song Dynasty. After the founding of New China, there were six saltworks in Tang Wei, including Baiyanshan saltworks, Dawei saltworks, Xinqiao saltworks, Danmen saltworks, Guo Chang saltworks and Hua 'ao saltworks. At present, the production area of Yantian is 978.87 hectares. The average annual output is about 60 thousand tons, and the quality is among the best in provinces and cities.
tidal energy
Tidal range is small in winter and large in summer, and tidal level is low in winter and high in summer. Tidal range is generally more than 3 meters. The tidal current in the eastern shallow sea rotates obviously, and there are seasonal differences in velocity. The maximum surface velocity is 138 cm/s, and the tidal current in Xiangshan Port is reciprocating, with an average of 100 cm/s and a maximum of184 cm/s. The tidal current in Shipu Port is reciprocating, with a maximum velocity of 300 cm/s at the entrance. ..