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(一) 河北省分山丘、坝上、山前平原、黑龙港地区和滨海平原五个类型区,总面积18.7万平方公里,耕地近亿亩。本省属大陆性半干旱季风气候区,冬季寒冷干燥,夏季炎热多雨,一般年份降雨量450～600毫米,但年内分布很不均匀,70%以上集中在七、八两月。三至五月正是春播和小麦生长的关键时间,降雨量很少,只相当全年雨量的十分之一,因此,形成了春旱秋涝的自然规律,对农业生产威胁很大。据历史记载,从1368年至1948年581年间,发生旱灾407次,涝灾383次,旱、涝交替为害。解放后,经过
(A) Hebei Province, sub-hills, dam, piedmont plain, Heilonggang and coastal plain five types of area, with a total area of 187,000 square kilometers, nearly 100 million mu of arable land. The province is a continental semi-arid monsoon climate zone, cold and dry in winter, hot and rainy in summer, the average annual rainfall of 450 to 600 mm, but the distribution is very uneven during the year, more than 70% concentrated in July and August. From March to May is the key point of spring sowing and wheat growth. Rainfall is very small, only about 1/10 of the annual rainfall. As a result, the natural laws of spring, drought and floods are formed, threatening agricultural production. According to historical records, from 1368 to 58 years in 1948, there were 407 droughts and 383 floods, causing alternating drought and flood damage. After liberation, after