Effective restoration strategies are needed to address habitat degradation that accompanies worldwide environmental change. One method used to enhance restoration outcomes is the leveraging of beneficial relationships (facilitation) among plants. In the southwestern United States, native mesquite trees (Prosopis spp.) are commonly planted to stabilize soil, but the value of using mesquite canopies for enhancing restoration success is unknown. We explored this possibility in an attempt to understand how common species, that both are and are not typically used for restoration, might differentially respond to mesquite canopies. We used a Bayesian multivariate generalized mixed model structure to analyze a dataset describing natural vegetation density in the Santa Rita Experimental Range, Arizona, United States. We found that more dominant species were not more likely to be distributed under mesquite. We also found that, while all of the focal species were more likely to be under mesquite with increased mesquite cover, they varied in the strength of their responses and the degree of saturation. Finally, we found that the aggressive invasive grass Eragrostis lehmanniana was found at lower incidences with increasing mesquite canopy cover, compared to the total species average as well as several of the natives investigated in this study. This work highlights the importance of being conscious of canopy size and continuity when considering understory species for restoration. This work also suggests that mesquite canopies can be used to provide a “safe site” for restoration species because competitive pressure from invasives is slightly reduced.

中文翻译：

---

确定原生豆科灌木冠下的修复机会

需要有效的恢复策略来应对伴随全球环境变化的栖息地退化。用于增强恢复结果的一种方法是利用植物之间的有益关系（促进）。在美国西南部，当地的豆科灌木树（Prosopisspp。）通常用于稳定土壤，但是使用豆科灌木冠提高恢复成功的价值尚不清楚。我们试图探讨这种可能性，以了解常见的和通常不用于恢复的物种对豆科灌木冠有不同的反应。我们使用贝叶斯多元广义混合模型结构来分析描述美国亚利桑那州圣塔丽塔实验岭自然植被密度的数据集。我们发现，更多的优势物种不太可能在豆科灌木下分布。我们还发现，虽然所有的焦点物种都更有可能在豆科灌木下生活，但豆科灌木覆盖率却有所提高，但它们的反应强度和饱和度却各不相同。最后，我们发现侵略性入侵草与总物种平均数以及本研究中调查的若干本地人相比，草皮草的草皮草的发生率较低，且豆科灌木冠层的覆盖率增加。这项工作凸显了在考虑进行林下物种恢复时意识到树冠大小和连续性的重要性。这项工作还表明，豆科灌木冠层可用于为恢复物种提供“安全场所”，因为入侵者的竞争压力会有所降低。