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本区位于四川盆地中部,介于龙泉山与华蓥山之间,总土地面积9万km~2,占全省的15％。境内地势起伏不平,海拔多在250—600m之间,丘陵面积可占总土地面积的90％左右,河谷平坝只占4％,仅在边缘地带有少量低山。本区热量资源十分丰富,年均温达17—18℃,≥10℃的积温为5200—6000℃,无霜期一般为300—340天,有利于各种作物和林木生长。但水资源明显少于四川盆地其他地区。年降水量为900—1000mm,而且降水季节分配不均,多年平均径流深只有340mm,加之气温高,蒸发量大,成为全省春、夏旱的中心区域。不少年份伏旱
The area is located in the central Sichuan Basin, between Longquan Mountain and Huaying Mountain, the total land area of 90,000 km ~ 2, accounting for 15% of the province. Undulating uneven terrain, mostly in the 250-600m above sea level, the hilly area can account for about 90% of the total land area, the valley Pingba only 4%, only a small amount of low mountains in the margins. The area is very rich in heat resources, the average annual temperature of 17-18 ℃, ≥ 10 ℃ accumulated temperature of 5200-6000 ℃, frost-free period is generally 300-340 days, is conducive to all kinds of crops and forest growth. However, water resources are significantly less than the rest of the Sichuan Basin. Annual precipitation of 900-1000mm, and the uneven distribution of precipitation season, the average annual runoff depth of only 340mm, combined with high temperature, evaporation, become the province’s spring, summer drought center. Many years of drought