华北沙地小黑杨人工林生长特性

Growth Characteristic of Populus×xiaohei Plantaion in Sand Land of North China

对华北沙地小黑杨人工林生长特性进行研究。结果表明：小黑杨树高生长要早于胸径生长,生长中后期单株之间对资源的竞争增强;树高连年生长量最大值与平均生长量最大值几乎同步出现,胸径亦如此,而材积的连年生长量最大值比平均生长量最大值要早3年左右出现;树高连年生长量在接近第6年时与平均生长量相交,胸径连年生长量和平均生长量在第10年左右时相交,材积连年生长量和平均生长量在接近第16年时相交;黑杨生长过程分为4个时期：第0-3年为幼林期,第4-14年为速生期,第15-16年为近熟期,第17-26年为成熟期;轮伐期在16年左右。

Growth characteristic of Populus x xiaohei plantaion had been studied in sand land of North China. The results showed： Tree height growth of P. × xiaohei was earlier than the breast diameter growth, the competition for resources grew cruelly among the trees in later growth period; The maximum of current annual increment and mean annual increment of tree height appeared nearly synchronously, so did the breast diameter, But the maximum of current annual increment of timber volume appeared much more earlier than the maximum of mean annual increment; The current annual increment and mean annual increment of tree height, breast diameter and timber volume were respectively intersected in about 6, 10 and close to 16 a; The growth process of P. × xiaohei was divided into four periods： 0 - 3 a was the young stand period, 4 - 14 a was the fast-growing period, 15 - 16 a was the near mature period, 17 - 26 a was the overmature period; The rotation of P. x xiaohei was 16 a.