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承德县飞播造林自1976年开始实施到1996年,已搞了20个年头,飞播造林作业总面积108万亩,有效面积86万亩,占飞播作业总面积的79.6%经调查,成效面积为25.37万亩,占有效面积的29.5%。早期飞播的油松已经郁闭成林,最高生长已达4.5米,胸径达7厘米,平均亩蓄积达3.5立方米,经济效益日趋显著。据统计,1976年飞播的张营播区,仅1995年幼林抚
The implementation of aerial seeding in Chengde County started in 1976 to 1996, and has been carried out for 20 years. The total area for aerial seeding and afforestation is 1.08 million mu and the effective area is 86 million mu, accounting for 79.6% of the total area for aerial seeding. After investigation, the effective area is 25.37 Mu, accounting for 29.5% of the effective area. Early flight of the pine has closed forest, the maximum growth has reached 4.5 meters, diameter 7 cm, an average of 3.5 cubic meters of accumulated acreage, increasingly significant economic benefits. According to statistics, Zhangying Broadcasting Area, which flew in 1976, was only young in 1995