人为干扰下西双版纳地区几种优势树种和濒危树种功能性状的比较(英文)

Winners and losers among tree species in Xishuangbanna: which traits are most important?

本研究针对版纳地区的木质树种进行调查和功能性状数据的采集，旨在找出在人为干扰环境下的“胜利者（Winner）”和“失败者（Loser）”并对其功能性状（比叶面积、木材密度、种子质量、最大树高）进行比较．结合2012-2014年西双版纳所有被子植物的濒危等级普查结果，选取12种“失败者”和最优势的15种“胜利者”进行比较．结果发现两组在比叶面积和木材密度方面有显著差异，而种子质量和最大树高之间的差异不显著，当排除了系统发育的影响之后，只有木材密度的差异仍然存在．在西双版纳地区，共有本地树种831种，但在干扰严重的生境中，能很好地适应的仅几十种，这些结果都证明“少数的胜利者和多数的失败者”这一模式对西双版纳地区的本地树种是适用的．

Massive human interference in natural ecosystems is resulting in a few ＂winners＂ and many ＂losers＂. However, the drivers of this winner-loser replacement pattern remain poorly understood. The aim of the study reported here was to identify winners among the tree flora of Xishuangbanna and compare their functional traits, specific leaf area （SLA）, wood density （WD）, seed mass （SM） and maximum height （MH） with previously identified losers （i.e., endangered species）. Fifteen native tree species were identified as winners from expert opinion, plot-based surveys of secondary forests and plotless surveys along roads. Twelve endangered tree species for which trait information could be obtained were used for comparison. Traits were compared with a Wilcoxon rank-sum test. Winners had significantly higher SLA, but lower WD. SM and MH did not differ significantly between groups. When the effects of phylogeny were removed by using phylogenetic generalized least squares, the difference in SLA became marginally insignificant. Principal component analysis resulted in two overlapping groups, showing that the selected traits were insufficient to distinguish winners and losers. Our results suggest that the ＂few winners, many losers＂ paradigm applies to trees in Xishuangbanna, with15 species accounting for most trees in the disturbed habitats sampled.