Park pruning prompts a competitive reversal of an exotic tree, Ligustrum lucidum, in urban forest of Japan
Park pruning prompts a competitive reversal of an exotic tree, Ligustrum lucidum, in urban forest of Japan
复制标题
公园修剪促使日本城市森林中一种外来树女女贞的竞争性逆转
DOI：
10.1007/s11252-016-0539-z
复制
发表时间：
2016
期刊：
影响因子：
2.9
通讯作者：
Naoko Yamashita
中科院分区：
文献类型：
--
作者：
Thomas Lei,Naoki Nishikawa;Naoko Yamashita
女贞，一种原产于中国的树，已经在日本归化，它经常被种植在公园和沿着。城市林地中的归化个体对本地物种具有不确定的竞争力，特别是在这些林地中进行频繁修剪的情况下。我们比较了健身相关的性状ofLigustrum对两个共同发生的本地物种：先锋树（野桐）和林下乔木（Eurya japonica）下修剪和un-pruned设置。在模拟林缘和林内两种环境和两种修枝处理（有或无）下，对3个树种的叶片和全株特征进行了生长试验。在模拟林缘条件下，女贞的树干生长量和最大光合速率（Amax）均低于野桐，说明乡土树种可以竞争性地抑制入侵扩展。修剪后，女贞在春季和夏季都能旺盛地重新萌发，在林缘和林内，其顶端生长量和总枝数分别显著高于白梧桐和芡实。此外，在相似的Amax之间的女贞和野桐，我们看到了一个逆转的竞争优势，有利于女贞在林缘。在森林内部，女贞表现出耐荫特性（即，Amax、叶绿素a/B和叶密度）与Euryabut相似，有更多的重新萌发芽，表明入侵者在弱光下也保持优势。人工干扰以公园修剪的形式明显提高了女贞的竞争力。这种管理做法可能会无意中增强外来物种在城市环境中的入侵性。
Ligustrum lucidum, a tree native to China has naturalized in Japan where it is often planted in parks and along roads. Naturalized individuals in urban woodlands have uncertain competitiveness against native species, particular in light of the frequent pruning undertaken in these woodlands. We compared fitness-related traits ofLigustrumagainst two co-occurring native species: a pioneer tree (Mallotus japonicus) and an understory tree (Eurya japonica) under pruned and un-pruned settings. A growth experiments where we assessed the leaf and whole plant characteristics of the 3 species under two environments simulating forest edge and forest interior, and two pruning treatments (with or without) was conducted. Under simulated forest edge without pruning,Ligustrumhad lower stem growth and Amax(maximum photosynthetic rate) thanMallotus, suggesting that native species can competitively suppress invasive expansion. With pruning, however,Ligustrumresprouted vigorously in both spring and summer with significantly higher apical growth and total shoots thanMallotusandEuryain forest edge and interior, respectively. Also, with similar Amaxbetween resprouts ofLigustrumandMallotus, we see a reversal of competitive advantage in favor ofLigustrumin forest edge. In the forest interior,Ligustrumexhibited shade tolerant properties (i.e., Amax, chlorophyll a/b, and leaf density) similar toEuryabut had more resprout shoots, suggesting that the invader also maintains an advantage under low light. The competitiveness ofLigustrumclearly increased with human disturbance in the form of park pruning. Such management practice can inadvertently enhance the invasiveness of exotic species in urban settings.