Watershed characteristics of Heqian River

Above Longxian County, it flows through Longshan Mountain with good vegetation, and it is a forest-producing area in mountain products. Between Longxian and Qianyang is the hilly area of loess original beam. Below Qianyang, it flows through the loess tableland area. The two-kilometer-long section near Fengjiashan is canyon-shaped. The lower valley is widened, the water flow is dispersed and the main branch is unknown. The main tributaries are Shiguangou, Xianyi River, Diaoyu River, Xiakou River and Luopu River.

In Longxian County, the mainstream area of Heqian River was called Longzhou Chuan Dao in ancient times. In addition, there are major rivers in Longxian County, such as Puyuchuan, Xianyichuan, Liangfuchuan, Lilinchuan and Guguanchuan. The first terrace of Zhouchuan, Heqian River mainstream valley and Gao Man Beach starts from Shenquan of Chengguan Town in the west and reaches the junction village of Dongfeng Town in the east, with a length of 36 kilometers and a width of about 5 kilometers, showing a northwest-southeast trend. Chengguan, Duyang, Dongfeng and other township governments are all in it, with dense population, fertile land and good water conservancy conditions. This is the county's grain, oil, vegetables and cash crops area. The first and second terraces on the banks of Puyuchuan and Puyuhe River and Gao Man Beach are located on the south side of He Qian River. From broom beach in the west to Weijiazhuang in the east, it is about 7 kilometers long and 25 kilometers wide. Tiancheng township government is located in central Sichuan. Puyuchuan, a famous big lake, was called "string cattails" in ancient times. Gong Yu said, "There are nine scorpions in the world, and this is one of them". According to the Records of Nine Domains in Sui Dynasty, "Jiuyuan County has a string of cattails". After a long period of siltation, the lake even burst into a river. There is a cloud in Longzhou Chronicle and Eight Scenes of Longzhou in Qing Dynasty: "When the peak meets the potential, it enters the valley, and the spring fragrance is fertile, and Sang Ma is everywhere, like the valley of Taihang Mountain". There are Bao (Ji)-Tian (Shui) Highway and Puyu Canal in the middle of Sichuan, with convenient transportation and developed water conservancy, which is one of the grain and oil producing areas in this county. Xianyichuan is located in the west of the county seat and the south of Caojiawan Township. From taoyuan village in the west to Liuqu Village in the east, it is named after Xianyi River. It is about 6 kilometers long and 3 kilometers wide. Ancient Post Road, Old Xian Yi Store and Liuqu Store. With flat and fertile land and abundant water resources, it is one of the grain producing areas in this county. Liang Fuchuan, north-south, starts from Pantaopo in the south and ends at Fuliang Village in the north, with a length of 12.5km and a width of 0.25- 1.5km ... Ya township government is located in central Sichuan. Lilin starts from Xipo Village, Ba Du Township, and ends in Yutou Village, Dongfeng Town, with a length of 7.5km, a width of 3km and a narrow mouth. Flat land, fertile soil, rich in marijuana, pepper, is the county's grain and oil, cash crops producing areas. Guguanchuan is located in the west of the county seat. From the west to the fork, east to the shop mouth. It is 7 kilometers long from east to west and 2 kilometers wide from north to south. There are thousands of rivers crossing the border in northern Sichuan and Gudian Canal in southern Sichuan. It belongs to the valley plain, with good water conservancy conditions, cultivated land 1030.2 mu and fertile land. It is the main producing area of wheat and flue-cured tobacco in Guguan Township. In Qianyang County, there are three terraces on the south bank of He Qian River and three terraces on the north bank, and only a part of the third terrace is reserved. The first terrace is distributed along Bao (Ji)-Ping (Liang) Highway and Qianlong Highway, with a width of 0.2 ~ 0.5 km, and its front edge is 5 ~ 10 m higher than Heqian River, with an altitude of 720 ~ 730 m.. The second terrace is distributed in the "binary" area of Chuantai, Shigou and Shuigou Township in Chengguan Town. The terrace is 0.5 ~ 2.5 kilometers wide, and its front edge is 20 ~ 30 meters above the water level of He Qian, 730 ~ 780 meters above sea level, and it is inclined to He Qian by 2 ~ 4 degrees. The third terrace is located in the area of Xiao Yuan, Duanfang and Qianyuan in front of the third terrace in Wenjiapo Township of Chengguan Town. The terrace width is 0.3 ~ 1 km, the front edge is 60 ~ 75 meters higher than the water surface of He Qian River, and the elevation is 750 ~ 820 meters, which inclines to Heqian River by 2.5 ~ 3 degrees.

Among the first-class tributaries of He Qian, there are several large gullies, such as Huichuan (also called Fengfang River), Jiankou River and Caobiyuchuan, with a width of 0.3 ~ 0.5 km. In Fengxiang County, the He Qian River Basin is called the modest terrace, which is located in the southwest of the county and adjacent to Baoji and Qianyang counties in the west. The jurisdiction includes 8 administrative villages in Changqing Township, with a population of10.9 million, covering an area of 33 square kilometers, accounting for 2.9% of the total area of the county. It is the first and second terrace of river alluvial, with an altitude of 588 ~ 750 meters. The overburden is Quaternary Holocene alluvial sand, gravel and loam, and the soil is mostly silt and fluvo-aquic soil. The cultivated land is 43,000 mu, which is one of the main grain producing areas in Fengxiang. The fruits produced are precocious and crisp. The area of soil erosion in this area is large, accounting for about 68% of the whole tableland area, with surface erosion as the main factor, with an average annual erosion modulus of 236 tons/square kilometer and an annual sediment discharge of 08,400 tons. 1974 After the completion of Fengjiashan Reservoir, the phenomenon of river erosion and bank collapse gradually decreased, and soil erosion was controlled.

During the Western Zhou Dynasty, thousands of rivers flowed into the Weihe River in Changqing Town, Fengxiang County, and Qin Feizi came to Guanzhong from Tianshui to shepherd the Zhou royal family. According to Records of the Historian Qin Benji, the youngest son and concubine of the ancestor of the Qin people lived in Tianshui and Lixian during the Zhou Dynasty and was good at raising horses. Today, where chencang district died in Baoji City, he was called by the Zhou Emperor to raise horses for the Zhou royal family, and was sealed in Qin by the Zhou royal family. This is a brand-new tribe in the history of China. From four years (763 BC) to two years (7 14 BC), during the 48 years after Qin people moved from Tianshui to the east, Hui people were also the capital of Qin people. "Historical Records of Qin Benji" said: "In three years (763 BC), Wen Gong marched eastward with 700 soldiers. Four years, to Wei Zhihui. It is said that' I won this in the Book of Changes in the pre-Qin period, and then I became a vassal'. Zhan Ji, that is, camp. " However, for a long time, the specific meeting place of Wei's deathbed has been a hot topic in the history circle. In 2004, archaeologists discovered a large number of pre-Qin tombs in Sunjia Nantou Village, Changqing Town, Fengxiang County, which proved that the Wei Hui Club buried in the vast fog was in Changqing Town where the Heqian River and the Weihe River met. Chencang district (formerly Baoji County) is located on the banks of Weihe River and He Qian, including all the townships (towns) of Guozhen, Yangjiagou and Yangping, and the Sichuan roads of He Qian, Shiyangmiao, Cang Shu, Diaowei, Tianwang, Panxi, Qingxi and Bayu townships (towns), with an area of 24 1. Chuan Dao has a relatively flat terrain, with the organic matter content of topsoil above 65438 0%, and 97% of the county is distributed in this area. At an altitude of 507-600 meters, the annual average sunshine is 2 100-2130 hours, which is greater than or equal to10 degrees Celsius, and the accumulated temperature is 4010-4,200 degrees Celsius. Surface water and groundwater reserves account for 82% of the county's total groundwater reserves, with per capita arable land 1.4 mu, of which per capita irrigated land 1. 1 mu and per capita labor force arable land 3.2 1 mu. The level of agricultural mechanization cultivation is above 70%, and the yield per mu of crops such as grain and rape is higher than the county level.