Litter feedbacks, evolutionary change and exotic plant invasion
Litter feedbacks, evolutionary change and exotic plant invasion
复制标题
DOI：
10.1111/j.1365-2745.2010.01781.x
复制
发表时间：
2011-03-01
影响因子：
5.5
通讯作者：
Molofsky, Jane
中科院分区：
文献类型：
--
作者：
Eppinga, Maarten B.;Kaproth, Matthew A.;Molofsky, Jane
1.了解外来植物入侵的驱动机制对于设计成功的入侵控制策略非常重要。以往的研究强调了不同的入侵机制，包括通过植物土壤反馈改变营养循环和进化改变更具竞争力的基因型。我们探讨了这两种机制相互影响外来植物入侵的可能性。使用最近的实验数据，在北美湿地的草（Phalaris）的入侵，我们参数化的营养物质和光的经典资源竞争模型，并扩展了这个模型，包括凋落物动态。我们还研究了在另一组最近的实验中观察到的进化变化的潜在影响。凋落物反馈和观察到的进化变化都可能增加Phalaris在入侵栖息地的表现。这些机制可能会相互放大，这种协同作用可能会加速Phalaris入侵已经存在的地区，导致高凋落物状态，Phalaris胜过其他物种。在养分供应不足的地区，如果没有蝴蝶兰的存在，凋落物反馈和进化变化的结合可能会导致从低凋落物、本地物种占主导地位的状态向高凋落物、蝴蝶兰占主导地位的状态转变。我们的模型结果表明，凋落物反馈和进化变化的重要性，可以在未来的实证研究中验证，通过非加性和非线性效应的凋落物添加实验，并通过增加凋落物：地上生物量的比例在植物群落与入侵和本地栖息地的Phalaris之间的地理比较。后者的结果可能是由于更多的入侵基因型的寄生凋落物的积累。合成.我们的研究说明了如何外来植物入侵可能会加剧凋落物反馈和进化变化之间的相互作用。这种相互作用可能会在入侵过程中产生积极的反馈，这表明即使是短期事件，如营养脉冲，也可能导致相对较大和快速的生态系统变化，这种变化可能是长期的，难以逆转。
1. Understanding the mechanisms driving exotic plant invasions is important for designing successful invader control strategies. Previous studies have highlighted different invasion mechanisms, including alteration of nutrient cycles through plant soil feedback and evolutionary change toward more competitive genotypes.2. We explored the possibility of these two mechanisms interactively affecting exotic plant invasion. Using data from recent experiments on the invasion of Phalaris arundinacea (Phalaris) in North American wetlands, we parameterized a classical resource competition model for nutrients and light, and expanded this model by including litter dynamics. We also examined the potential effects of evolutionary changes as observed in another set of recent experiments.3. Both litter feedbacks and observed evolutionary changes may increase Phalaris' performance in invasive habitats. These mechanisms may amplify each other and this synergy may accelerate Phalaris invasion in areas where it is already present, leading to a high-litter state with Phalaris outcompeting other species. In areas with low nutrient supply where Phalaris is not yet present, a combination of litter feedbacks and evolutionary change may induce a critical transition from a low-litter, native-species-dominated state toward a high-litter, Phalaris-dominated state.4. Our model results suggest that the importance of litter feedbacks and evolutionary change could be verified in future empirical studies through non-additive and nonlinear effects in litter addition experiments, and by increased litter : above-ground biomass ratios in biogeographical comparisons between plant communities with Phalaris in invasive and native habitats. The latter result may be caused by the accumulation of more recalcitrant litter from invasive genotypes.5. Synthesis. Our study illustrates how exotic plant invasions may be exacerbated by the interaction between litter feedbacks and evolutionary change. This interaction may induce a positive feedback in the invasion process, suggesting that even short-term events, such as a nutrient pulse, may lead to relatively large and rapid ecosystem shifts that could be long-lasting and difficult to reverse.