What is the geographical environment of Zizhong County?

Zizhong County is located in the middle of Sichuan Basin and the middle reaches of Tuojiang River, with a land span of 29 34? ~30 24? East longitude 104 27? ~ 105 07? In the east, Anyue County, ziyang and Dongxing District of Neijiang City; South of Neijiang city center, Weiyuan County; Renshou County, Weiyuan County and Meishan City in the west; It is connected to Yanjiang District of Ziyang in the north. It is 64.49 kilometers long from east to west, 52. 13 kilometers wide from north to south, with an area of 1733.96 square kilometers.

Zizhong is located in the inclined stratum at the end of the northwest wing of Roewe Dome, which is a gently inclined stratum with a dip angle of 2 ~ 5 degrees and a basic earthquake fracture of 6 degrees. Affected by rock formations, the terrain is high in the southwest and low in the east and northeast. The highest point in China (Shanshu 'ao, xinqiao town) is 739.8 meters above sea level, and the lowest point (Tuojiang water in yinshan town) is 298 meters above sea level. The relative height difference of the mountain is relatively small, about 439 meters. The landform types are mainly hills (flat deep hills, middle shallow hills, gentle hills and wide valleys), with an altitude of 300-550m and an area of1478.96km2, accounting for 85% of the total area. Low mountains and narrow valleys, 500 ~ 700 meters above sea level, covering an area of 255 square kilometers, accounting for 15% of the total area.

Zizhong County has a subtropical humid monsoon climate with four distinct seasons, mild climate, abundant rainfall, early spring, long summer, short autumn and winter, no intense heat in summer, no severe cold in winter and long frost-free period. 84 days in spring (February 26th to May 20th), 8 days in summer1/kloc-0 (May 2nd1to September 15) and 76 days in autumn (September 16 to16544). 5438+ 10 is the coldest in June, with an average monthly temperature of 6 ~ 8℃. It is the hottest in July, with an average monthly temperature of 26 ~ 30℃. The average temperature over the years (198 1 to 20 10) is17.4℃ (17.7℃ in 20/kloc-4 years), and the highest year is18. The extreme maximum temperature is 465,438+0.9℃ (38.4℃ in 2065,438+04) and the minimum temperature is-2.4℃ (0.4℃ in 2065,438+04). The average frost-free period for many years is 332 days, with the longest being 365 days (1969, 1970, 1972, 1979) and the shortest being 293 days (1963). The average surface temperature is 19.3℃, and the extreme maximum surface temperature is 68.3℃. The extreme minimum surface temperature over the years is -3.5℃. The annual average rainfall is 977.6 mm (20 14 years 984.2 mm), the annual average evaporation is 1062.9 mm, and the annual average relative humidity is 8 1%. The average sunshine hours over the years are 1088.6 hours (20 1 102. 1 hour in 2004), with a maximum of 1558.6 hours and a minimum of 1978. The annual average sunny days are 178 days, accounting for 49% of the whole year; Cloudy day 142, accounting for 39%; Cloudy days (weather between cloudy and sunny days) last for 45 days, accounting for 12%. The annual average wind speed 1.9 m/s, and the air pressure is 965 ~ 983 hectopascals.

Zizhong County has four soil types: paddy soil, purple soil, yellow loam, old and new alluvial soil, and 14 soil genera (including 7 paddy soil, 3 purple soil, 2 yellow loam and 2 alluvial soil). The total cultivated land area in the county is 84,373.74 hectares, including 68 173 hectares of basic farmland, with diverse soil types, rich nutrients and thick soil layers.