杨树速生丰产林生长发育规律的研究

STUDY ON GROWTH PATTERN OF THE FAST-GROWING AND HIGH YIELD POPLAR PLANTATION

为提高杨树速生丰产林的经营效果,对喀左小钻杨生长规律进行了研究。结果表明,喀左小钻杨树高连年生长量最大值出现在第7年,平均生长量最大值出现在7～11a;胸径连年生长量最大值出现在第6年,平均生长量最大值出现在6～11a;材积连年生长量最大值出现在第8年。把工艺成熟和数量成熟结合起来加以考虑,喀左小钻杨的轮伐期为13～15a。经分析,喀左小钻杨生长过程分3期,1～5a为幼林期,6～11a为速生期;12～15a为近成熟期,应主伐利用。

For the plantation of Populus simonii×P. nigra var. italica, the biggest height current annual increment is in the seventh year, the biggest mean annual increment is from the seventh to the eleventh year. The biggest diameter at breast height current annual increment is in the sixth year,the biggest mean annual increment is from the sixth to the eleventh year. The biggest volume annual increment is in the eighth year. The rotation of P. simonii × P. nigra var. italica is from thirteen to fifteen year from the consideration of technological and quantitative maturity. The growth cycle of the poplar plantation can be divided into three periods:from the first to fifth year is young growth period; from sixth to eleventh year is fast-growing period; from twelth to the fifteeth year is maturity period, and should be cut and used.