The geographical environment of Aksu

Aksu city is located in the depths of Eurasia, far from the ocean, and has typical warm temperate continental arid climate characteristics.

Precipitation is scarce, evaporation is large, climate is dry and frost-free period is long.

Spring is dry and windy, accompanied by floating dust and sand blowing, and there are many thunderstorms in summer, sometimes accompanied by local strong convective weather such as heavy rain and hail. The weather is better in autumn, the rainfall is obviously reduced, the temperature is suitable, the winter is relatively warm, and there is less rain and snow.

sunlight

Aksu city has dry air, less clouds and more sunny days.

Distribution characteristics are more in the south and less in the north.

The annual sunshine hours are 2505 ~ 3 136 hours, the average sunshine hours are 2 809 hours, and the annual sunshine percentage is 60% ~ 70%.

The total solar radiation is 130 ~ 140 kW/cm2.

temperature

The annual average temperature in Aksu is 10.8℃, the extreme maximum temperature is 40.7℃, and the extreme minimum temperature is -27.6℃.

The days when the daily average temperature is higher than 10℃ are 197 days.

cumulative temperature

Aksu city has good light and heat conditions and rich heat resources.

The annual average is ≥ 10℃, and the stable accumulated temperature reaches 3953℃, ≥ 15℃? The stable accumulated temperature reaches 3299℃, and the stable accumulated temperature of ≥20℃ reaches 1857℃.

frost-free period

Aksu has a long frost-free period, which is generally 190 ~ 25 1 day, with the longest frost-free period reaching 295 days and the shortest frost-free period reaching 160 days.

soil temperature

The average ground temperature in Aksu is12.0℃ ~15.1℃, the extreme maximum ground temperature is 62.4℃ ~ 7 1℃, and the extreme minimum ground temperature is -27℃~ 20℃.

The average freezing period in Aksu area is generally from the end of June 165438+ to the beginning of February, with the earliest being June 65438+ 10/0 and the latest being June 65438+February 2 1.

The depth of frozen soil is generally 40 ~ 60 cm, and the deepest part can reach 80 cm.

The thawing date of 10 cm soil layer is from March 7th to 20th, with an average of11March.

wind speed

Due to the barrier of Tianshan Mountain, the annual wind speed in Aksu City is relatively low, with annual average wind speed 1.5m/s, maximum wind speed 10 ~ 15m/s and historical maximum wind speed 18.5m/s,

wind direction

The wind direction is mostly northwest wind or west wind, with the largest wind speed in spring, followed by summer and the smallest wind speed in autumn and winter.

deposit

The annual precipitation in Aksu City is generally 60 ~ 90 mm, with an average annual precipitation of 80.4 mm. The main rainfall period is from May to September, accounting for 70% ~ 80% of the annual precipitation. 1 1 mm has the least precipitation, and the average monthly precipitation is only 1 mm.

Snowfall is mainly concentrated between 65438+February and February of the following year.

evaporate

The annual evaporation is 1643 ~ 2202 mm, which is 27 times of the annual precipitation.

In a year, it is the largest in May-August, with an average monthly evaporation of 260-360 mm, and the smallest in winter, only about 20 mm The Xia Dong difference is more than 13 times, and the average annual evaporation is1948 mm.

Aksu River is one of the three major international rivers in Xinjiang and the main water supply river of Tarim River.

The average amount of water that the Aksu River flows into the Tarim River for many years accounts for 73.2% of the three headwaters in the upper reaches of the Tarim River (Hetian River, Yeerqiang River and Aksu River), which plays a decisive role in the formation, development and evolution of the Tarim River.

Aksu River: an international river in China and Kyrgyzstan, with a total drainage area of 52,000 square kilometers, including 6,543,800 square kilometers in Kyrgyzstan and 33,000 square kilometers in China, with an annual runoff of 8.059 billion cubic meters. Aksu River is formed by the confluence of two tributaries, Kumarak River and Tuoshigan River, which respectively flow through Akqi County and Aksu City in Kizilsu Autonomous Prefecture, Wushi County and Wensu County in Aksu region.

After flowing through 12km, Aksu River is divided into two tributaries, the new river in the east and the old river in the west.

Kumarak River: Originating from Keshhar Mountain in Kyrgyzstan, it flows into Pahadi Village, Wensu County, China after crossing the Keshhar Ridge, and joins the Tuoshi River to enter the Aksu River. The total length of the river is 293km, of which the foreign exchange water area in China is 10 150km2, and the catchment area in China is 2306km, accounting for only 17.99% of the total water area.

The average annual runoff for many years is 4.788 billion cubic meters.

The maximum annual runoff of the river is 6.9965438 billion cubic meters, and the minimum annual runoff is 3.644 billion cubic meters.

The river drop is 336 meters, the water surface ratio is reduced to 9.2‰, and the river section is V-shaped, with steep slope and strong erosion.

Tosh River: Originating from Koksal Mountain in Kyrgyzstan, it flows through Akqi County in Kizilsu Kirgiz Autonomous Prefecture, Wushi County and Wensu County in Aksu Prefecture, and joins the Kurakurak River in the south of Pahadi Village and flows into Aksu River.

The total length of the river is 457 kilometers, including 140 kilometers in Kyrgyzstan and 3 17 kilometers in China. The average annual runoff for many years is 2.663 billion cubic meters, the maximum annual runoff is 2.767 billion cubic meters, and the minimum annual runoff is10.78 billion cubic meters.

The river drop is 47 1m, and the water surface ratio is reduced to 4. 1%.

The upstream valley is narrow and the current is swift. The river banks are mostly intermittent terraces or stepped valley slopes, and the riverbed is sandy pebble riverbed.

Laoda River: Located in the southwest of Aksu City, it originated from the Aixi barrage of Aksu River and then entered the West Bridge water diversion hub. After passing through Topluk Township, Ayikule Township, Kumbashi Township, Yingairike Township, Bagto Gerakl Township and Wuluchele Town in Aksu City, it flows into the new river below Kaldun Public Security Farm, with a total length of 1 15.8km and an average annual runoff of 26.

In the early 1980s, with the completion of Xiqiao Hydropower Station of the First Agricultural Division of the Production and Construction Corps, the upper reaches of the Laoda River were basically channelized and replaced by Awati main canal.

Xinda River: Originating at the tail end of Aksu River, it flows directly into Xinda River after being diverted from Ailixi barrage, and flows into Tarim River from Airike Town of Awati Baishi via Yiganqi Township of Aksu City, Tugeman Township of Baishi, Lezhen Town of Carata, Topluk Township, Kumbashi Township and Xiaojia Shuiwen Station, with a total length of 132km and an average annual runoff of 35.

The runoff distribution of Xinhe River is extremely uneven during the year, mainly from June to August. After the water from Xinhe River flows into Tarim River according to the planning requirements, the rest of the water flows into Tabei Irrigation District and Tarnum Irrigation District of No.1 Agricultural Division of Corps.

Duolang River (also known as Duolang Canal) is an ancient man-made river, which was built in the 25th year of Qing Daoguang (1845). Water is taken from the Duolang Canal Diversion Hub of Kumarak River, flows from north to south through four townships (towns) such as Yiganqi Township, thoroughbred farm, Baishi Tugeman Township and Carata Lezhen in Aksu City, and flows into Aksu New River at Namat Retreat Canal. .

Duolanghe Irrigation District is 78km long from north to south and 2 ~10km wide from east to west.

Tarim River: It is the largest river flowing through Aksu City and the longest inland river in China.

Tarim River is located in the southeast of Aksu City/the First Agricultural Division of the Production and Construction Corps/the Xiao jacket near Jiahezi Natural Town of Kloc-0/50 km. It is formed by the confluence of Aksu River, Hotan River, Kashigar River and Yeerqiang River, with a total length of 2 179km, a total drainage area of 198000 square kilometers and a city boundary of 164km. 1 100 million cubic meters, the minimum low flow rate is 0.42 cubic meters per second, and the maximum peak flow rate is 1.750? Cubic meters per second, the river often swings from north to south, with the flood season from July to September and the dry season in winter. In flood season, Populus euphratica forests and desert grasslands on both sides can be irrigated, which usually plays a role in drainage.

During the flood season from July to August every year, the flow velocity is 0.7 ~ 2.3m/s, the water depth is 1 ~ 7.5m, and the water width is 40 ~ 600m. In normal water period, the flow velocity is 0.3 ~ 1m/s, the water depth is 1 ~ 3.4m, the water width is 20 ~ 100m, 165438+ 10, which freezes in late October and thaws in early March, and the ice thickness is 0.3 ~ 0. ..

The annual average sediment concentration is 4.89 kg/m3.