西双版纳热带植物园引种植物物候特征比较

迁地保护是生物多样性保护的重要手段之一，前期的植物引种研究呵为迁地保护提供必要的理论支持。通过对西双版纳热带植物园内不同来源的引种植物和本地植物的4个物候期（萌叶期、落叶期、开花期和果熟期）分布格局及其气候影响因子进行对比，阐明引种植物对环境的适应性和对策。结果表明，引种植物比本地植物萌叶生长盛期更长，但对低温和干旱更加敏感的引种植物，在旱季其落叶比例明显高于本地植物，而3、4月由于气温的回升，使引种植物和本地植物在雨季之前就进入了萌叶盛期。而在繁殖物候方面，由于受气候因子影响较小，引种植物和本地植物的开花期和果熟期格局季节性表现都不明显。且规律性不强。总体上，各来源地的引种植物能根据环境的改变形成相应的生长与繁殖适应对策，可较好地适应西双版纳的环境。

A Comparison of the Phenological Characteristics of Introduced Plant Species in the Xishuangbanna Tropical Botanical Garden

Ex situ conservation is considered to be one of the most important ways for biodiversity conservation. Probe into introduced plant species that are to be conserved can provide some essential references for ex situ conservation. Here, we compared introduced and native plant species in Xishuangbanna Tropical Botanical Garden in terms of the patterns of 4 phenophases -- leaf flushing, leaf shedding, flowering and fruit ripening. We also analyzed the influence of climatic factors to illustrate the adaptability of these plants. The introduced species had a longer flushing period than the native ones, but their percentage of leaf shedding in the dry season was higher because of their higher sensitivity to low temperature and drought. With the increase in temperature in March and April, all plant species enter a flushing period before the rainy season. Flowering and fruit ripening patterns of both the introduced and native species showed both a weak seasonality and regularity because of their low susceptibility to climatic factors. In general, the introduced species develop proper growth and reproductive strategies to adapt to the environment in Xishuangbanna.