Lianas reduce community-level canopy tree reproduction in a Panamanian forest

Lianas are a key component of tropical forests, where they compete intensely with trees, reducing tree recruitment, growth and survival. One of the most important potential outcomes of liana competition is the reduction of tree reproduction; however, no previous study has experimentally determined the effects of lianas on tree reproduction beyond a single tree species.
We used a large-scale liana removal experiment to quantify the effect of lianas on community-level canopy and understorey tree and palm reproduction. In 2011, we removed lianas from eight 6,400-m2 plots (eight plots served as controls) and surveyed understorey tree reproduction in 2012, canopy tree and palm reproduction in 2013, and a second census of all plants in 2016.
We found that lianas significantly reduced canopy tree community flowering and fruiting after liana removal. Two years after liana removal, the number of canopy trees with fruits was 173% higher, fruiting individuals had 50% more of their canopy covered...

藤本植物（Lianas）是热带森林的关键组成部分，它们与树木激烈竞争，降低树木的更新、生长和存活率。藤本植物竞争最重要的潜在结果之一是减少树木繁殖；然而，此前尚无研究通过实验确定藤本植物对单一树种以外树木繁殖的影响。

我们通过大规模藤本植物移除实验，量化了藤本植物对群落水平上层和下层树木及棕榈繁殖的影响。2011年，我们从8个6400平方米的样地中移除藤本植物（另有8个样地作为对照），并于2012年调查下层树木繁殖情况，2013年调查上层树木和棕榈繁殖情况，2016年对所有植物进行第二次普查。

我们发现，藤本植物显著抑制上层树木群落的开花和结果，这一结论通过藤本植物移除实验得以验证。移除藤本植物两年后，结果的上层树木数量增加了173%，结果个体的冠层覆盖面积增加了50%……