Caojing physical geography

Caojing Town is located in the southeast edge of the dished depression in Taihu Lake Basin. The town is located in the middle of high plains, with flat and low-lying terrain in the south and high plains in the southeast. The highest ground elevation is 4.4m based on Wusong datum, the northern part is the central plain, the lowest ground elevation is 3. 17m, and the average ground elevation is 4.05m The general ground elevation of reservoirs, Jianguo, Ruanxiang, Jiangzhuang and Hutang villages is 3.8m to 4m; In seven villages, such as Zengfeng, Donghai, Guangjin, Barracks, Shaji, Haiyan and Yuhai, the ground elevation is generally more than 4 meters.

Coasts and beaches

The coastline of Caojing Town is long 1 1 km, and it runs in an arc to the northeast and southwest. It starts from Yangjiayuan, Zengfeng Village in the south and enters Jia Zhu Village, Qiaohu Town, Fengxian District via Zengfeng Village, Shojimura, Yuhai Village and Haiya Village.

1. Changes in coastline

Historically, the coastline of this town has changed greatly. According to textual research, Shaji Road, which starts from Longqiao in the east and extends to the north in the west, is an ancient Shagang body, which is about 6000 years ago and is a relic of the ancient coast. To the east of Shagang, the coast continues to extend outward. During the Three Kingdoms period, the coast was far south of Jinshan Island. Since the Eastern Jin Dynasty, the coastline continued to collapse, and by the end of the Tang Dynasty, the coastline had approached the foot of Jinshan. During the Song Dynasty, Jinshan fell into a sea of people and became an island. At this time, the coast is 2.5 kilometers southeast of Que.

In the middle of Ming Dynasty, the coast collapsed from east to west. In the middle of Jiajing, the coast of the missing section was eroded by the tidal head, and a large area of land fell into the sea, forming a concave gap from Zhelin to Caojing. During the Hongzhi period (1488- 1505), Dongxin Wharf and Xixin Wharf in the south of Caojing Town collapsed into the sea. During the Kangxi period of the Qing Dynasty, Hujiagang Fort was also invaded by seawater.

During the reign of Qing Qianlong and Jiaqing (1736- 1820), the peak of tidal current began to move westward, and the coastline around Caojing collapsed. However, the coastline west of Haicun is still dominated by collapse. In Daoguang 15 (1835), the outer retaining pond in the west of Yucun completely collapsed, and the retaining pond in the east has been preserved to this day because of its wide beach. Later, the beach continued to rise, forming the current coastline.

2. Caojing Beach

In the first year of Jiaqing in Qing Dynasty (1796), the tidal wave crest moved westward to the west of Haicun. Originally, the washed sea villages began to deposit on the east coast, and the coastline became a silted coast. In the seventeenth year of Daoguang (1837), after the bank protection of Pantou Dam in Qijiadun was built, the tidal wave crest point in Jinshanzui area was stable and the sedimentation in Caojing Beach was accelerated. At the end of the Qing Dynasty and the beginning of the Republic of China, there was 1-3 Litan outside Dong Tang, which was close to the coastline in the early Yuan Dynasty. Measured in July, 1985, the beach section has been1450m wide. During the 66 years from 1929 to 1985, the growth at home and abroad was more than 1400 meters, with an average annual growth of 2l meters.

The distance between 0 meter line and seawall in Caojing section 1958 198 1 year 1500m, 1985 1500m, with an average annual increase of 24m.

Caojing beach is 4.7 meters above Wusong point, and its slope gradually inclines to the sea l/372.

1968 February to 65438+February, the commune built Caojing Xintang 3.062 km and 3,225 mu of beach at the place 500m to1200m from Yongzheng Shitang (Shanghai-Hangzhou Highway), which was first used for agriculture and salt production, and then 900 mu of prawn pond and 200 mu of freshwater fish pond were dug.

1986165438+1October, the then township and county water conservancy bureaus jointly built a 4.429-kilometer seawall 400-700 meters away from the newly-built pond in 1968, enclosing 2622.07 mu of tidal flats, including 2022 in the township.

199265438+On February 26th, a new pond built 600-700 meters from Zhangjiashe, Shitang, Yongzheng (Shanghai-Hangzhou Highway) to Laotagang Bridge in Nanshe South was closed by Municipal Finance Bureau and Water Conservancy Bureau, and 1800 mu of beach land was enclosed, which needed planning and development.

1April 1996, Tang Wei was 10 square kilometers. This beach, which has been surrounded many times, is now Shanghai Chemical Industry Zone.

River course and water level

Caojing Town has large and small rivers 1279, with a total length of 425.7 kilometers. The density of river network is 9.46 kilometers per square kilometer, which is the highest in the county. Among them, there are 3 county-level rivers, which flow through the whole town 19.97 km; There are 4 county-town boundary rivers, which flow through the town length11.65km; Town river 17, with a total length of 41.66 km; Village-level rivers 1255, with a total length of 352.42 kilometers.

Original main river course

East-west trend

1, Xianshuitang (including Changyan Port) starts from Longquan Port in the west and ends at the border of Qiao Hu Town in Fengxian District in the east, with a territory of 3.3 kilometers. 1972 dredging Longquan port to Hejia port in Changyan village is 2.7 kilometers long.

2. Yaojia Port starts from Longquan Port in the east and ends in Kannonji, Zhuxing Town in the west. Within the town 1.67 km, dredging within the town 1957.

3. Meilinjing starts from Shihe River in the east and reaches the border of Qiao Hu Town in Fengxian District in the west. The territory of this town is 1.25 km. Dredge the town at 1959.

4. North Hengtang starts from the canal in the east and ends in the west Hengtang, with a total length of 3 kilometers.

5. Nanhengtang starts from the canal in the east and ends in the west, with a total length of 2.55 kilometers.

6. The military and civilians start from Meilinjing in the east and reach Hengtang in the west, with a total length of 4.2 kilometers.

7. Tiedian Port starts from the Canal in the east and ends at Longquan Port in the west. Mayor 1.66 km, dredging 1954.

North-south trend

1, Longquan Port starts from the east gate of Jinshan in the south and connects with Yexietang in the north, with a total length of19.53km and a domestic section of 7.25km.. Dredging in 1955 and 1977.

2. The marble south river starts from the south gate of jinshanwei and ends at Meilinjing in the north, with a total length of 15.6 km and the town's territory of 7.5 km. 1950, 1956, and 200 1 are dredged for three times, allowing navigation to 300-ton ships.

3. Moutou River starts from flagpole port in the south and ends at Tonghai in the north, with a total length of1.8km. ..

4. The tanker port is 2.6 kilometers long, starting from the sea in the south and reaching Hengtang in the north.

Bending trend

1, Jiangzhuang Port starts from He Jie Port in the north, ends in Jiangzhuang Town and ends in Longquan Port in the east, with a total length of 2.8km..

2. Ruanxiang City starts from Minghua Village in the south of the Yangtze River in the east, reaches Ruanxiang small market town, and reaches Ying Long Temple in Qiaohu Township, Fengxian County in the east, with a territory of 2.54 kilometers.

2. Newly dug major rivers

East-west trend

1. The middle canal starts from Longquan Port in the east and ends at the trunk lane in the west, with a total length of 12.66 km. The section from Longquan Port to Huanglangyang in this town is 2. 1 km, which is dug at 1978.

2. Minghua Central starts from Longquan Port in the west and ends at Group 6 of Jingxi Village in the east, with a total length of 2. 15km. 1972.

3. Qianjin Port starts from the Central Canal in the west and ends at Longquan Port in the east, with a total length of 0.64 km. Excavated in 197 1 year.

4. Xinfeng Port starts from Jiangzhuang Port in the west and ends at Longquan Port in the east, with a total length of 1.74km. Excavated in 197 1 year.

5. South Central starts from the Stone River in the east and ends at the preparatory port in the west, with a total length of 2.05 kilometers. 1973.

6. North Central Hexi starts from Shaxi Xikou of Shaji Village and ends at Meilinjing in the east, with a total length of 1.8km.. 1975.

7. Tonghai starts from Yunshi River in the east and reaches Longquan Port in the west, with a total length of 5.22 kilometers. Excavated at 1959. Dredged in 1970, it is the north-south main river channel of the town.

8. Xindong Seaport starts from Yunshi River in the east and ends at Longquan Port in the west, with a total length of 5.22km. It is excavated at 200 1 and can be used for navigation of 300-ton ships.

North-south trend

1. It is planned to start from Shihe River in the south and reach Tonghai in the north, with a total length of 4.0 15km .. It was excavated in 197 1 year.

2. Guangjin Center starts from flagpole port in Henan and ends at Tonghai in the north, with a total length of 2.7 kilometers. 1978.

3. The center of Venus starts from the estuary of Henan and ends at the central canal in the north, with a total length of 2.7 kilometers. Excavated in 197 1 year.

Bending trend

Stafford Port in flug starts from Tonghai to Group 3 of Ogari Village in the north, and ends at Longquan Port in the west. The mayor is 5.93 kilometers. The southern section is excavated at 1953, and the northern section is excavated at 1956.

3. Hydrology and tide level

1. The inland river cultural area belongs to the Huangpu River system, and the inland water level is affected by the Huangpu River tide. Because it is far away from Huangpu River, and the river network in the territory is dense, the water flow is slow and the tidal range changes little. At low tide, the water level in the south is higher than that in the north, especially during the rainstorm, a large amount of water in the upper reaches of Yunshi River and Longquan Port flows downwards, which is easy to cause local high water level and is easy to be flooded in case of typhoon and flood. The historical highest water level of the Yunshi River appeared in1September 3 1963, reaching 4.28 meters. The lowest tide level appeared on April 5th 1963, only1.76m..

2. The waters in this sea area belong to Hangzhou Bay, and the tidal current is controlled by the inter-shore current on the north bank and the tidal current in Jinshan deep trough. Tidal current belongs to non-semidiurnal shallow water tide, with two high tides and two low tides in one day and night. 1 month has tidal changes, generally from vernal equinox to autumnal equinox, the night tide is greater than the diurnal tide, and the diurnal tide is greater than the night tide from autumnal equinox to the following vernal equinox. Tidal level is obviously influenced by meteorological tides. When typhoon strikes in summer, the tide level rises obviously, and when cold air blows frequently in winter, the tide level drops obviously. The average high tide lasts 5 hours and 24 minutes, and the low tide lasts 7 hours and 2 minutes, with a difference of 1 hour and 38 minutes. The tidal current is a shallow water reciprocating current, the period is consistent with the tidal level, the maximum velocity is 1.77m/s, and the high tide is greater than the low tide. At high tide, seawater flows into the open sea; at low tide, the tidal current approaches Beisong, and the sediment in the north of Haicun quickly deposits, forming a beach.

climate

Caojing Town is located in the mid-latitude, on the coast of the East China Sea, and belongs to the subtropical monsoon region. The climate is characterized by four distinct seasons, short spring and autumn, long winter and summer, mild and humid climate, abundant rainfall, abundant sunshine and long frost-free period, which is suitable for the growth and development of animals and plants. However, it is also affected by the alternation of cold and warm air, and the climate is changeable, and there are also disastrous weather such as typhoon, extreme heat, rainstorm and high tide.

1. temperature

The annual average temperature is 65438 05.5℃, with a range of 65438 05℃ to 65438 06.5℃. The average temperature in July and August is about 27.7℃, and the average temperature in 1 month is about 3.65438 0℃.

Spring lasts about 70 days from early April to early June (that is, from Qingming to awning). The weather is getting warmer, and the daily average temperature is 10 ~ 22℃. Since 1959, the average temperature in spring in this town has been 17.3℃, and the temperature is suddenly cold and warm, but there is basically no severe cold weather below 0℃, and the weather above 30℃ is rare.

From mid-June to mid-September in summer (that is, from summer solstice to cold dew), the weather is getting hotter and hotter, and the average daily temperature is above 20℃. Since 1959, the average summer temperature in this town is 26.2℃, and July and August are the hottest weather in the whole year, with the average daily maximum temperature around 3 1.5℃. The maximum temperature is above 35℃, with an average of 6-7 days per year, reaching 197 1 6 days per year and138C on August 6, 966.

Autumn lasts about 60 days from late September to165438+1mid-October (that is, light snow in first frost). The weather turned cold, and the average daily temperature was between 12℃ and 2 1℃. Since 1959, the average temperature in autumn in this town has been 16.7℃, and the high temperature above 30℃ has appeared for several days in autumn, commonly known as "autumn tiger". 165438+1There was a cold wave at the beginning of October, and the temperature dropped obviously, generally it could drop to about 10℃.

Winter is165438+/kloc-0 from late October to March of the following year (i.e. from heavy snow to vernal equinox), about 130 days. The weather is cold and dry, and the average daily temperature is below 10℃. Since 1959, the average temperature in winter in this town is 5.7℃, and the average temperature in June of 1 year is about 3℃. 1977 65438+1October 3 1 daily minimum temperature-10.8℃.

2. sunshine

The town is located at 30.47 degrees north latitude, with an average total solar radiation of 1 12.5 1 kcal per square meter and an average sunshine of 2049 hours. Sunny days and cloudy days are different every year, and the sunshine hours are also different, which varies greatly between years and months. During the 23 years from 1959 to 198 1, the maximum sunshine hours are 197 1, and the minimum sunshine hours are 1959,180/kloc. In a year, the sunshine hours in February are the least, and the monthly average sunshine 123.2 hours. 1959 February sunshine 4 1.5 hours. August has the most sunshine hours, with an average monthly sunshine of 258.6 hours. 1967 August sunshine is 363.4 hours.

Step 3: Rain

The annual average rainfall is about 1 100 mm, and the annual rainfall days are about 136 days. Due to the influence of monsoon intensity and alternating times of cold and warm air, rainfall changes greatly. The rainfall in rainy years is about twice that in dry years. 1977 rainfall is 13 15.3mm, 1978 rainfall is 7 1 1.6mm ... The most rainy day in the whole year is now 1977, reaching/kloc. The minimum rainfall sunrise is now 1967, which is 108 days. Winter is cold and rainy, and summer is wet and rainy. The rainfall from April to September accounts for about 68% of the annual rainfall, and the rainfall is mainly concentrated in three rainy seasons.

During the spring rain from April to May, the average annual rainfall was about 233.2 mm, accounting for 2 1.4% of the annual rainfall, with an average rainy day of 29.2 days. The general rainfall process is concentrated in late April to mid-May.

During the Meiyu period from June to July, the rainfall was concentrated, rainy and continuous, with high humidity and sultry weather. The average rainfall over the years is 248.3 mm, accounting for 22.8% of the annual rainfall. The average rainy day is 28.5 days. Especially from mid-June to early July, the average rainy day 19.5438+0 days. However, the length of meiyu period varies from year to year, which is very different. In recent years, Ren Mei first appeared in1974may19; Appeared on June 28th at the latest,1969; The earliest appearance of plum blossom was1961June 15, and the latest appearance was1977 on July 28th. Meiyu period occurred in 1974 and lasted for 67 days, including 37 rainy days with rainfall of 466.6 mm; 1964 occurs for 6 days at the shortest, and it rains for 6 days, with rainfall of 93.6 mm.

During the autumn rain from August to September, the average rainfall over the years is 260mm, accounting for 23.8% of the annual rainfall. The average rainy day is 20.5 days, and the rainfall process mainly occurs when the cold air in the north meets the wet warm air flow in the ocean, and sometimes the typhoon transits to bring heavy rain.

4. frost and fog

The frost-free period in this town is relatively long, from 1959 to 198 1 year, with an average frost-free period of 228 days, including frost period of about 137 days, frost-free period of 3 18 days and frost day of 47 days. Frost generally begins in mid-June 165438+ 10 and ends in mid-April of the following year. Agricultural proverb "Snow breaks in Qingming Festival, frost breaks in Grain Rain". The frost period is different in different years. In recent years, the earliest first frost is now197910/0/October 22nd, and the latest first frost is now1970101October 30th. The earliest final frost sunrise is now1979 March 6th, and the latest final frost sunrise is now1962 April19th.

Fog may appear in the whole year 12 months, most in autumn and winter every year, usually from midnight to the early morning of the next day. 1959 ~ 1985 The average foggy day is 42. 1 day. Fog days occurred in 1979 in 2008, with 83 foggy days. The youngest ones appeared in 1959, 1964, 1967, 27 days each for three years. The town is located in the coastal area, and fog appears from time to time, especially in the eastern villages. Mostly sea fog, mostly in autumn and winter. They came suddenly and went quickly, like a misty cloud, drizzling.

5. Bioclimatology

Early warning of rain: the foot of the tide rings, the moon is dizzy, the rainbow rises in the west, the snow is frosty, the water tank sweats, the toad barks, the dragonfly flies low, the ants move, the ground returns to the tide, the cat eats grass, the rainbow is high and the sun is low, the river is covered with moss, the turtle comes out of the water, and the smoke is not in the sky.

Sunny omen: northeast rainbow, cicada singing, September frog singing, Jinshan Qing, spider web, chickens and ducks staying early.

Warning wind: fog and dew in the three dynasties, sun halo, eastern daylight, sunrise climbing the cloud wall.