加拿大一枝黄花对庐山自然保护区林地植物多样性及其季节动态的影响

Seasonal Dynamics of Plant Diversity in Woodland Invaded by Solidago canadensis(Asteraceae) in Lushan Nature Reserve

为揭示加拿大一枝黄花(Solidago canadensis)在庐山自然保护区的扩散过程及其对林地的可能影响及规律,调查了庐山自然保护区周边加拿大一枝黄花的分布现状,并在庐山自然保护区加拿大一枝黄花入侵群落设置了长期监测样地,对7个1 m×1 m的样方进行了植物多样性季节变化的定点研究。结果发现,加拿大一枝黄花已在庐山自然保护区周边大量发生,尤其是在城镇周边和高速公路两侧。庐山自然保护区森林覆盖率较高,光弱、多雾天气不利于加拿大一枝黄花的生长与繁殖,因此,加拿大一枝黄花在样地内的扩散较慢。但是,加拿大一枝黄花在所处的植物群落草本层一直长期存在,并导致样地内部分本土草本植物多度下降,尤其在每年10月期间群落植物多样性下降到最低。研究结果表明,加拿大一枝黄花也有可能在郁闭度较好的林地实现种群更新,对自然保护区的潜在影响不容忽视。

Solidago canadensis （Asteraceae）,a noxious invasive plant in central and eastern China,has invaded woodland in Lushan Natural Reserve of Jiangxi Province,central China. To reveal the spread pattern of S. canadensis and the possible effects on biodiversity in this woodland,we investigated the seasonal dynamics of S. canadensis over two years and the species diversity of the main native plants by establishing seven plots. Results showed that low sunlight and predominance of foggy weather of the Lushan Nature Reserve were not suitable for the growth of S. canadensis, while S. canadensis was always the dominant species in the herb layer and caused a significant decline in species diversity in this layer, especially in au- tumn （October）. Although low sunlight in the woodland inhibited the growth and the further spread of S. canadensis,this plant invader was able to survive and regenerate by sexual and clonal reproduction. Therefore, the invasion of S. canadensis into the woodlands and nearby habitats in Lushan Natural Reserve remains a possibility and deserves further study.