First grade, 0: 48, 6: 48.

The next day, 1:36 7:36.

Grade three, 2: 24, 8: 24.

Grade 4, 3: 12 9: 12.

Fifth grade, 4 o'clock 10 o'clock.

On the sixth day, 4:48 10:48.

On the seventh day, 5:36 1 1:36.

Day 8, 6:24 12:24.

On the ninth day, 7: 12 13: 12.

Day 10, 8:00 14:00.

Hydrological climate:

Coastal rivers have large sediment concentration, vast beaches and serious siltation. The main rivers flowing into the bay are the Yellow River, Haihe River, Jiyun Canal and Luanhe River.

The Yellow River is famous for its less water and more sand. The annual average runoff is 44 billion cubic meters (Huayuankou Hydrological Station near Zhengzhou), and the annual average sediment discharge is 65.438+0.6 billion tons, accounting for more than 90% of the sediment discharge in Bohai Bay, which is the main source of modern sediments in Bohai Bay.

② The average annual runoff of Haihe River system is 2110.60 billion cubic meters, and the average annual sediment discharge is 6 million tons. After the completion of 1958 Haihe sluice, the runoff decreased sharply, with an average annual runoff of only 71100,000 cubic meters and an annual sediment discharge of less than 300,000 tons, which greatly reduced the impact on the development of the Bohai Bay landform.

③ Jiyun Canal is a storage and discharge channel, with an average annual runoff of 740 million cubic meters in 1922 ~ 1957 and an average annual sediment discharge of 700 million ~1000000 tons. After 1958 sluice is built, the annual runoff and annual sediment discharge are 66 million cubic meters and 15600 tons respectively.

④ The average runoff of Luanhe River for many years is 4.79 billion cubic meters, and the annual sediment discharge is 226.5438+10,000 tons. It can be seen from the above that the influx and diffusion of a large amount of sediment from the Yellow River is the main source of sediment in Bohai Bay. Although the migration of Luanhe River sediment to the southwest into the sea is rare, it can not be ignored, which makes the underwater siltation shallow and the beach surface enlarged in Bohai Bay. For example, on the beach surface of Bao Bei-Jianhe River, from 1958 to 1984, the average annual extension to the sea is 1.5 km, and the average annual increase in sedimentary thickness is 1 1.5 cm. It is rare in other sea areas.

Refer to Baidu Encyclopedia for the above content? Bohai Gulf