河北小五台山天然白桦林草本多样性影响因素研究

Study on effect factors of herb diversity of Betula platyphylla in Xiaowutai Mountain of Hebei

主要研究了河北省小五台山地区天然白桦林草本多样性与地形因子及林木生长因子之间的关系。研究结果表明:(1)林木生长因子与坡度呈正相关关系,其中坡度与冠幅相关性为极显著(p<0.01),与树高和胸径相关性为显著(p<0.05);海拔与胸径、冠幅成负相关关系,且相关性达到显著(p<0.05);(2)郁闭度、树高、胸径、冠幅基本与草本生物多样性呈负相关,其中郁闭度与草本多样性之间相关性较为明显,其他生长因子与草本多样性之间相关性均不显著;(3)在海拔1600 m—2000 m之间,草本多样性随着海拔的升高未呈现出规律性变化,草本多样性指数均波动范围较小;(4)坡形、坡位等对草本多样性影响较小,而坡度与草本多样性关系较为明显;各项草本多样性指数变化趋势基本相同,整体上均随着坡度的增加而呈现递减的趋势。

This paper studied the relationship between herbal diversity of Betulaplatyphylla in Xiaowutai with terrain factors and forest growth factors. The results showed that the forest growth factor was positively correlated with slope, and the relation between canopy and slope was significant （p〈0.01）; the relation between slope with tree height and DBH reached a significant level （p〈0.05）; altitude was negatively correlated with canopy size and DBH, and the relation reached a significant level （p〈0.05）. The herbal diversity was negatively correlated with canopy density, tree height, DBH and canopy size, and the relationship between canopy density with herbal diversity was obvious, and the relationship between herbal diversity with the other forest growth factors was not significant. The herbal diversity index showed an irregular fluctuation with increased altitude on the elevation of 1600 m to 2000 m, and it fluctuated on small-scale. The effect of slope shape and slope position to herbal diversity was relatively small, but the relation between slope and herbal diversity was significant; the changes of herbal diversity index showed the same trend of decreasing with increased slope as a whole.