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一、自然条件和引种概况: 我所位于宜昌县东部丘陵地带,地理位置东经110°51’,北纬30°48’,海拔100-180米,年平均气温17℃左右,最高气温40℃,出现在七月份,最低气温-5℃,历史极端低温-22.5℃(1977年元月);年雨量800-1000毫米,多集中于4-7月;无霜期230-240天,早霜期11月上旬,晚霜期3月末至4月初,土壤为砾岩风化而成的红黄色粘土,PH值5.5-7之间,土层深度大多只有100厘米,少数仅50-90厘米.
First, the natural conditions and the introduction of introduction: I am located in the eastern hilly Yichang County, the geographical location of longitude 110 ° 51 ’, latitude 30 ° 48’, 100-180 meters above sea level, the annual average temperature of about 17 ℃, the maximum temperature of 40 ℃, there In July, the lowest temperature -5 ℃, the history of extreme low temperature - 22. 5 ℃ (January 1977); annual rainfall 800-1000 mm, mostly concentrated in April-July; frost-free period 230-240 days, early frost in early November, Night frost late March to early April, the soil is made of conglomerate weathered red-yellow clay, PH value between 5.5-7, the depth of the soil is only 100 cm, a few only 50-90 cm.