ABSTRACT Background: Promoting changes in abiotic conditions and ecosystem processes, such as decomposition, is a mechanism by which some exotic plant species displace native plants and become invasive. Aims: We monitored ramets of Hedychium coronarium over 30 months to estimate the litter decay rate, biomass dynamics and litter accumulation over time in riparian sites invaded by the species in southeastern Brazil. Methods: We measured the number, height, emergence and mortality of ramets in three environments invaded by H. coronarium (natural, rural and urban). We also measured litter decay in situ and in in vitro experiments. We used sinusoidal models to describe height fluctuation and exponential models to simulate litter decay and litter accumulation. Results: Ramets of H. coronarium showed high seasonal variation in terms of height and emergence, as well as low litter decay. Accordingly, our models predicted high litter production and a seasonal pattern of litter accumulation in invaded sites. Conclusions: H. coronarium produces a great amount of litter, which shows slow decay and hence seems to affect decomposition processes. Investigating seasonal variation on the effects of invasive species on ecosystem functioning shed light on the factors driving the success and impact of invasive plants.

中文翻译：

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亚洲入侵植物 Hedychium coronarium J. König (Zingiberaceae) 热带南美洲河岸带的凋落物积累和生物量动态

摘要背景：促进非生物条件和生态系统过程的变化，例如分解，是一些外来植物物种取代本地植物并成为入侵者的一种机制。目的：我们在 30 个月内监测了 Hedychium coronarium 的分株，以估计巴西东南部物种入侵的河岸地点随时间推移的凋落物衰减率、生物量动态和凋落物积累。方法：我们测量了 H. coronarium 入侵的三种环境（自然、农村和城市）中分株的数量、高度、出现和死亡率。我们还测量了原位和体外实验中的凋落物衰减。我们使用正弦模型来描述高度波动和指数模型来模拟凋落物衰减和垃圾堆积。结果：H. 冠层在高度和羽化方面表现出很大的季节性变化，以及低凋落物腐烂。因此，我们的模型预测了入侵地点的高凋落物产量和凋落物积累的季节性模式。结论：H. coronarium 产生大量枯枝落叶，腐烂缓慢，因此似乎影响分解过程。调查入侵物种对生态系统功能影响的季节性变化揭示了驱动入侵植物成功和影响的因素。