冀北山地油松人工林天然更新研究

Study on the natural regeneration of Pinus tabuliformis plantation in the northern mountain of Hebei province

油松是易于天然更新的树种。对冀北山地油松人工林天然更新情况进行了调查,样方测定结果显示油松天然更新能力较强,更新幼树密度26~283株/100 m2,达到了常规造林的密度要求;更新幼树的树高结构呈左偏单峰形,年龄结构呈下降型种群;微地形对更新幼树的株数有明显影响,不平坦的地形相较于平地有利于更新;更新幼树的空间格局呈典型的聚集型分布状态。采用样带法测定油松母树种子传播距离主要在2倍树高以内,平均最远距离约2.8倍树高。建议今后应改变油松林皆伐再造林的生产模式,利用其天然更新能力对现有成熟龄、近熟龄人工林及疏林等进行人工促进更新;更新中适当采取人工措施如破土、疏伐、简易整地等辅助措施,保留带宽不超过4倍树高。

The Natural Regeneration of Pinus tabuliformis plantation was investigated in the northern mountain of Hebei Province. The result of quadrat investigation are showed that Pinus tabuliformis plantation has strong ability of natural regeneration, the sapling density is range 26 to 283 per hundred square meters.It can meet the requirement of normal afforestation. The sapling height structure is unimodal and left-avertence curve. The age structure showed that it is a diminishing population. The microtopography have a significant impact to amount of sapling, and the uneven microtopography is better. The spatial pattern of sapling is typical aggregated distribution. The propagation distance of seed-tree is mostly less than double tree height, the average farthest distance is 2.8 times.