Native woody legumes respond more negatively to extreme drought than invasive ones

本地木本豆科植物比外来入侵木本豆科植物对极端干旱事件的负面响应更强

Plant invasion potentially will be affected by increased extreme drought events and deposition of atmospheric N.However,results from previous research indicate that it is not clear as to how extreme drought,N deposition and their interaction affect alien plant invasion,in particular for the invasive woody legumes.We conducted a greenhouse experiment with three invasive and three native woody species of legumes(Fabaceae).We grew plants in extreme drought and in well-watered conditions combined with low and high levels of N and compared plant height,number of leaves and biomass production and allocation.Growth of native woody legumes was suppressed more by extreme drought than that of invasive woody legumes.Although an increase in soil N availability decreased the root mass fraction of plants of all species,it did not affect their overall performance.We found that invasive woody legumes can tolerate the adverse effects of the prolonged extreme drought better than native woody legumes.These results enhance our understanding of the effects of drought due to climate change on the invasion of alien woody legumes.

植物入侵可能会受到极端干旱事件增加和大气氮沉降的影响。然而,极端干旱、氮沉降及其相互作用如何影响外来木本豆科植物的成功入侵尚不清楚。本研究选取3种入侵木本豆科植物和3种本地木本豆科植物,开展温室控制实验。分别将这些植物种植在不同干旱处理(极端干旱和对照)和不同氮水平(低氮和高氮)下,然后对比分析两类植物的株高、叶片数、生物量以及根质量分数的差异。研究结果表明,极端干旱对本地木本豆科植物生长的抑制效应强于入侵木本豆科植物。尽管土壤氮素有效性的增加降低了植物的根质量分数,但这并不影响植物的整体表现。入侵木本豆科植物比本地木本豆科植物更能耐受长期极端干旱的负面效应。本研究加深了我们对气候变化导致的干旱事件如何影响外来木本豆科植物入侵的了解。