不同坡地条件木荷人工林的生长差异研究

Study on Growth Differences of 18-year-old Plantation of Schima superba Gardn. et Champ. among Different Slope Orientation and Slope Positions

对不同坡向、坡位之间18a生木荷(Schima superba Gardn.et Champ.)人工林进行生长差异分析,结果表明:1)不同坡向、坡位的木荷林胸径、树高和单株材积均有极显著差异;阳坡下坡位的胸径均值为9.17cm,树高均值为8.10m,单株材积均值为0.031 617m3;阴坡下坡位的胸径均值为8.84cm,树高均值为7.83m,单株材积均值为0.027 923m3;阳坡或阴坡下坡位的各生长指标均值均分别超过中坡位,中坡位均分别超过上坡位;阳坡生长优于阴坡;下坡位生长情况最佳,中坡位次之,上坡位最差。2)不同坡向之间的冠幅和活枝下高均有极显著差异,死枝下高(P>0.05)差异不显著;不同坡位之间的冠幅、活枝下高、死枝下高均有极显著差异;树高、胸径分别与活枝下高、死枝下高及冠幅等指标之间存在极显著相关关系,表明林分生长力的强弱与其自然整枝能力的强弱关系密切。3)由不同坡向的不同坡位DBH/H值可知,木荷林的生长随坡位的上升均表现出树高生长逐渐替代径向生长;郁闭的木荷林分,受到干扰较少,仅产生少量萌枝,表明萌枝的产生与干扰有关。

Growth differences of Schima superba Gardn. et Champ. at different slope orientation and slope positions were studied. The result showed that there was significant difference in DBH,tree height,individual volume at different slope orientation and slope positions. In the southern slope,the average DBH at downslope was 9. 17 cm. The average tree height at downslope was 8. 10 m. The average individual volume at downslope was 0. 031617m3. In the north slope,the average DBH at downslope was 8. 84 cm. The average tree height at downslope was 7. 83 m. The average individual volume at downslope was0. 027923m3. All growth mean indexes of mid-slope were higher respectively than those at upslope,which was less than those downslope. Sunny slope orientation was better than shady slope orientation. Growth at downslope was best,was better mid-slope and worst upslope. Slope orientation and slope positions were the important factors influencing canopy of plantations. There were significant differences in slope orientation at living branch height and crown,except dead branch height. There were significant differences in different slope positions at living branches height,dead branch height and crown. The tree height and DBH were respectively significantly associated with living branch height,dead branch height and crown. The mean DBH / H showed that height growth can be seen instead of radial growth with the rising of slope position. There was less interference in the stand of Schima superba Gardn. et Champ.,which produces a small amount of sprouting. It showed that sprouting was related to interference.