Data from: The negative effect of lianas on tree growth varies with tree species and season

Lianas reduce tree growth, reproduction, and survival in tropical forests. Liana competition can be particularly intense in isolated forest fragments, where liana densities are high, and thus host tree infestation is common. Furthermore, lianas appear to grow particularly well during seasonal drought, when they may compete particularly intensely with trees. Few studies, however, have experimentally quantified the seasonal effects of liana competition on multiple tree species in tropical forests. We used a liana-removal experiment in a forest fragment in southeastern Brazil to test whether the effects of lianas on tree growth varies with season and tree species identity. We conducted monthly diameter measurements using dendrometer bands on 88 individuals of five tree species for 24 months. We found that lianas had a stronger negative effect on some tree species during the wet season compared to the dry season. Furthermore, lianas significantly reduced the diameter growth of two tree species but had no effect on the other three tree species. The strong negative effect of lianas on some trees, particularly during the wet season, indicates that the effect of lianas on trees varies both seasonally and with tree species identity.

在热带森林中，藤本植物（liana）会抑制树木的生长、繁殖与存活。在孤立的森林片段生境中，藤本植物的竞争压力往往更为强烈——此类生境内藤本种群密度较高，寄主树木被侵染的现象十分普遍。此外，藤本植物在季节性干旱时期的生长态势尤为旺盛，此时它们与树木的资源竞争会愈发激烈。然而，目前鲜有研究通过受控实验，量化热带森林中藤本植物的竞争对多树种的季节性影响效应。本研究于巴西东南部一处森林片段开展藤本移除实验，旨在验证藤本植物对树木生长的影响是否随季节波动，以及是否因树种属性而异。研究期间，我们采用测径带（dendrometer band）对5个树种共88株个体进行了为期24个月的月度胸径监测。结果表明，相较于旱季，藤本植物在湿季对部分树种的抑制作用更强。进一步分析显示，藤本植物显著降低了其中2个树种的胸径生长速率，但对其余3个树种未产生明显影响。藤本植物对部分树木的强烈抑制效应（尤其在湿季），证实了其对树木的影响兼具季节性差异与树种特异性。