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一、天津市的自然气候特点天津市地形南北长(400公里),东西窄(150公里),产棉区集中在南北两端,南部以吴桥县为主,包括交河、宁津、盐山、献县及河间等县,棉田面积占全市棉田总面积的70%以上,为天津市主要产棉区,土质大部为砂壤土、壤土及轻粘壤土。武清北部产棉区以武清县为主。包括静海、壩县及天津市郊区,棉田面积比南部棉区少,土质多为黑红粘土和盐碱地。气候特点是全年无霜期180天左右(南部较长,北部较短),较平年4—8月分平均气温为22°,降雨量约为450毫米,蒸发量约为1200毫米。今年有些反常,4—8月分平均气温23.4℃比平年高1.4℃;降雨量北部仍为450多毫米,而南部仅253.3毫米,比平年少300多毫米:蒸发量为1,478.6毫米,比平年大
First, the natural climate characteristics of Tianjin Tianjin terrain north-south long (400 km), things narrow (150 km), cotton-producing areas concentrated in the north and south ends, mainly in the southern Wuqiao County, including cross river, Ningjin, Xianxian and Hejian counties, cotton area accounts for more than 70% of the total area of the city’s cotton fields, Tianjin is the main cotton-producing areas, most of the soil is sandy loam, loam and light clay loam. Wuqing northern cotton-producing areas to Wuqing mainly. Including Jinghai, dam county and suburb of Tianjin, cotton area less than the southern cotton area, soil mostly black and red clay and saline land. The climatic feature is that the annual frost-free period is about 180 days (longer in the south and shorter in the north), with an average temperature of 22 ° in April-August than in the same period, with a rainfall of about 450 mm and an evaporation of about 1200 mm. This year some abnormalities, April-August sub-average temperature of 23.4 ℃ higher than the average of 1.4 ℃; rainfall is still 450 mm in the north, while only 253.3 mm in the south, more than 300 mm less than normal: evaporation of 1,478.6 mm, larger than normal