西非布基纳法索共和国道路网干扰对路边环境Pteleopsis suberosa更新的影响

沿铺面道路和未铺面道路,调查了4种路边环境（缓变区,附近区,中间区和非缓变区）的Pteleopsis suberosa苗木种群结构和其更新机制。沿道路平行线调查了2m×5m的203块样方,记录每个样方内的种苗总数和每个种苗的活枝数。通过评价基部和水平枝芽和挖掘地下根系来确定更新机制。结果表明,在4种路边环境中,单一主干和多主干苗木的总密度及各自密度都有明显的变化（p〈0.05）。所有苗木都是无性繁殖而来,根出条占98%,眠芽蘖和萌生各占1%左右。研究表明,铺面道路和未铺面道路缓变区中等水平土壤的干扰可以刺激Pteleopsis suberosa根出条更新 道路类型（铺面和未铺面）对苗木密度没有影响,但对路边立地的P.suberosa种群的萌生能力来说,道路类型是一个重要变量。P.suberosa是一个耐干扰的物种,受道路网干扰后可以通过根出条繁殖。

Impact of disturbance from roadworks on Pteleopsis suberosa regeneration in roadside environments in Burkina Faso, West Africa

The seedling population structure of Pteleopsis suberosa and their regeneration mechanisms were investigated in four roadside environments (graded, adjacent, intermediate and ungraded areas) along paved and unpaved roads in West Africa. A total of 203 quadrats of 2 m × 5 m in size were surveyed and placed along transects parallel to the roads. Within each quadrat, the total number of seedlings and the number of living shoots per seedling base were recorded. Regeneration mechanisms were determined by assessing basal and aerial sprouts and excavating the root systems below ground level. The results show that the total seedling density and the densities of single- and multi-stemmed individuals varied significantly (p < 0.05) among the four roadside environments. However, all seedlings were produced asexually; root suckers were predominant (98%) compared to water sprout (1%) and coppices (less than 1%). This study demonstrates that an intermediate level of soil disturbance from grading along paved and unpaved roads may stimulate P. suberosa regeneration by root suckering. Road type (paved and unpaved) did not affect seedling density, but was a highly significant variable in relation to the coppicing ability of P. suberosa populations in roadside sites. In conclusion, P. suberosa is a disturbance-tolerant species which can proliferate mainly by root suckering after roadwork disturbance.