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通过对民勤绿洲二白杨和新疆杨林带生长状况调查及单株解析木分析表明 :杨树林带生长迅速 ,高生长进程具有前期速生性 ,5年生树高可达 1 0 m左右 ,1 5龄树高生长已稳定在 1 4～ 1 9m,平均连年生长量为速生期的 1 /3,基本达到了防护成熟状态 ;径生长和材积生长都具有后期速生性 ,速生期可延长到 2 0年以后 ,年均径生长量为 1 .0～ 1 .5 cm,年均材积生长量为 0 .1～ 0 .3m3;最后以林带的防护成熟、经济成熟和数量成熟综合分析确定新疆杨和二白杨林带更新年龄分别为 2 5年和 2 0年。
Through the investigation on the growth of Populus euphratica Populus and Poplar Belt in Minqin Oasis and wood analysis of single plant, the results showed that poplar forest belonged to rapid growth and rapid growth in the early stage. The 5-year-old tree height was about 10 m, Tree height growth has stabilized at 14 ~ 19m, average annual growth rate of 1/3 of fast-growing period, basically reached the state of protective maturity; diameter growth and volume growth have the late rapid growth, fast-growing period can be extended to 20 years After that, the average annual growth was 1.0 ~ 1.5 cm, and the average annual volume growth was 0.1-1.3 m 3. Finally, the results of protective maturation, economic maturity and quantitative maturity of Xinjiang were used to determine Xinjiang Yang and II Poplar forest renewal age were 25 years and 20 years.