School of Nature Conservation, Beijing Forestry University, Beijing, China.
Department of Biology, University of Fribourg, Fribourg, Switzerland.
Plant Biol (Stuttg). 2020 Jul;22(4):591-599. doi: 10.1111/plb.13101. Epub 2020 Mar 18.
Highly biodiversity communities have been shown to better resist plant invasions through complementarity effects. Species richness (SR) is a widely used biodiversity metric but lacks explanatory power when there are only a few species. Communities with low SR can have a wide variety of phylogenetic diversities (PD), which might allow for a better prediction of invasibility. We assessed the effect of diversity reduction of a wetland community assemblage typical of the Beijing area on biotic resistance to invasion of the exotic weed Alternanthera philoxeroides and compared the reduction in SR and PD in predicting community invasibility. The eight studied resident species performed similarly when grown alone and when grown in eight-species communities together with the invasive A. philoxeroides. Variation partitioning showed that PD contributed more to variation in both A. philoxeroides traits and community indicators than SR. All A. philoxeroides traits and community indicators, except for evenness index, showed a linear relationship with PD. However, only stem length of A. philoxeroides differed between the one- and two-species treatments, and the diversity index of the communities differed between the one- and two-species treatments and between the one- and four-species treatments. Our results showed that in natural or semi-natural wetlands with relatively low SR, PD may be a better predictor of invasibility than SR. When designing management strategies for mitigating A. philoxeroides invasion, deliberately raising PD is expected to be more efficient than simply increasing species number.
高生物多样性群落通过互补效应被证明能够更好地抵抗植物入侵。物种丰富度（SR）是一种广泛使用的生物多样性指标，但在物种较少时缺乏解释力。SR 较低的群落可能具有广泛的系统发育多样性（PD），这可能有助于更好地预测可入侵性。我们评估了北京地区典型湿地群落组合多样性减少对入侵性外来杂草空心莲子草生物抗性的影响，并比较了 SR 和 PD 减少对群落可入侵性的预测。当单独种植和与入侵性空心莲子草一起种植在八物种群落中时，所研究的八种本地物种的表现相似。方差分解表明，PD 对空心莲子草的特征和群落指标的变异贡献大于 SR。除均匀度指数外，空心莲子草的所有特征和群落指标均与 PD 呈线性关系。然而，只有空心莲子草的茎长在一物种和两物种处理之间存在差异，而群落的多样性指数在一物种和两物种处理以及一物种和四物种处理之间存在差异。我们的研究结果表明，在 SR 相对较低的自然或半自然湿地中，PD 可能比 SR 更好地预测可入侵性。在设计减轻空心莲子草入侵的管理策略时，预计有意提高 PD 比简单增加物种数量更有效。
