The geographical environment of Chengdu

Chengdu is located in the transition zone from the western Sichuan Plateau to the Sichuan Basin, and has its own unique climate resources: First, the climate in the east and west is different. Due to the disparity between the east and the west of Chengdu, with the rapid increase of altitude, the heat decreased sharply, so the pattern of warm in the east and cool in the west appeared. Moreover, in the mountainous areas around the western basin, the temperature difference between mountains at the same time can be several degrees, and even there are many climate types from bottom to top, such as warm temperate zone, temperate zone, cold temperate zone and cold zone. This vertical change of heat has created very favorable conditions for Chengdu to develop agriculture, especially diversified economy. Second, the winter is wet and cold, the spring is early, the frost-free period is long, the four seasons are distinct and the heat is rich. The annual average temperature is about 16℃, the annual average active accumulated temperature ≥ 10℃ is 4700 ~ 5300℃, and the frost-free period is 278 days. The first frost period generally appears at the end of 1 1, and the final frost period is generally in late February, with Leng Yue in winter (66. The weather with the lowest temperature below 0℃ mainly occurs in the middle and late February of 65438+and the early October of 65438+ 10, and a small part occurs in the middle and late October of 65438+ 10. The average temperature is 1 ~ 2℃ higher than that in the middle and lower reaches of the Yangtze River at the same latitude, and it enters spring half a month earlier. Third, there is little spring rain in winter, rainy in summer and autumn, and abundant rainfall. The average annual precipitation is 900 ~ 1300mm, and the annual precipitation changes little. The ratio of the maximum annual precipitation to the minimum annual precipitation is about 2: 1. Fourth, light, heat and water are basically in the same season, and the combination of climate resources is reasonable, which is very conducive to biological reproduction. Fifth, the wind speed is small, and the wind speed in the vast plains and hilly areas is1~1.5m/s; There are few sunny days, the sunshine rate is between 24% and 32%, the annual average sunshine hours 1042 ~ 14 12 hours, and the annual average total solar radiation is 83.0 ~ 94.9 km/cm2.

The extreme minimum temperature in Chengdu is -5.9℃, with most districts and counties appearing in 65438+February and a few in 65438+ 10. According to the monthly data of wind direction, wind speed and precipitation climate in Chengdu published on the website of Chengdu Meteorological Bureau, Chengdu belongs to the humid monsoon climate zone in the middle subtropical zone, and the most common wind direction in Chengdu is static wind. The second wind direction: north wind in June, July and August, and north-northeast wind in other months. Chengdu is rich in mineral resources. First, there are many kinds of metal minerals such as iron, titanium, vanadium, copper, lead, zinc, aluminum, gold, silver, strontium and rare earth, and there are more than 60 kinds of nonmetallic mineral resources such as calcium fern, serpentine, gypsum, calcite, limestone, marble, coal and natural gas. Second, the distribution is relatively concentrated. There are more than 400 large and small mining areas in the city, and most of the mineral resources are relatively concentrated. The proven coal reserves 1.46 billion tons are mainly concentrated in Pengzhou, Dujiangyan, chongzhou city and Dayi counties in the western marginal mountainous areas. The proven reserves of natural gas are167.7 billion cubic meters, and the prospective reserves are 422 1 100 million cubic meters, mainly concentrated in Pujiang County, Qionglai City, Dayi County, Dujiangyan City and Jintang County. Glauberite reserves rank first in China, reaching 9.862 billion tons, mainly concentrated in Xinjin County and Shuangliu District. Various metal mineral resources in Pengzhou are relatively concentrated. The third is * * * ore.