Positive interactions influence the assembly of plant communities globally, particularly in stressful environments such as deserts. However, few studies have measured the intensity and relative importance of positive interactions involving native and invasive species along aridity gradients. These measures are essential for predicting how dryland communities will respond to biological invasions and environmental change. Here, we measured the intensity and importance of positive associations formed between native shrubs and the annual plant community, which included highly invasive Bromus madritensis ssp. rubens (“B. rubens”) and native neighbours, along an aridity gradient across the Mojave and San Joaquin Deserts.

中文翻译：

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与本地灌木的积极联系对于外来入侵者非常重要，但对于整个干旱梯度而言，却不是本地年度社区

积极的互动会影响全球植物群落的组装，尤其是在沙漠等压力较大的环境中。但是，很少有研究测量沿干旱梯度涉及本地和入侵物种的正向相互作用的强度和相对重要性。这些措施对于预测旱地社区将如何应对生物入侵和环境变化至关重要。在这里，我们测量了天然灌木和一年生植物群落之间形成的正向关联的强度和重要性，其中包括高度侵入性的Bromus madritensis ssp。鲁本斯（“ B. rubens ”）和当地邻居，沿莫哈韦沙漠和圣华金沙漠的干旱梯度分布。