Light acquisition and utilization may be vital to the successful invasion of invasive plants. Photosynthetic area and photosynthetic capacity are the two key indicators affecting light acquisition and utilization. Nevertheless, few investigators have verified the contribution intensity of photosynthetic area and photosynthetic capacity of invasive plants to their growth performance in the invaded communities, particularly under various invasion levels. This study aimed to evaluate the contribution intensity of photosynthetic area and photosynthetic capacity of the invasive weed Erigeron canadensis L. to its growth performance under various invasion levels. This study also elucidated the functional divergences in photosynthetic area and photosynthetic capacity between E. canadensis and natives in the communities under various invasion levels of E. canadensis. The invasion levels of E. canadensis were classified into the following three types: (I) without invasion, (II) light level of invasion, and (III) high level of invasion based on its relative abundance in the invaded communities. Photosynthetic capacity of E. canadensis was significantly greater than that of natives in the communities under E. canadensis invasion regardless of the invasion level. Photosynthetic area of E. canadensis was significantly lower than that of natives in the communities under E. canadensis invasion regardless of the invasion level. The direct effects and the indirect effects of photosynthetic capacity on the growth performance of E. canadensis were obviously higher than those of photosynthetic area. Thus, photosynthetic capacity of E. canadensis may be more critical to its growth performance than photosynthetic area during its invasion process.

光的获取和利用对于入侵植物的成功入侵可能至关重要。光合面积和光合能力是影响光的获取和利用的两个关键指标。然而，很少有研究人员验证入侵植物的光合面积和光合能力对其在入侵群落中生长性能的贡献强度，特别是在不同入侵水平下。本研究旨在评价不同入侵水平下入侵杂草加拿大飞蓬的光合面积和光合能力对其生长性能的贡献强度。该研究还阐明了E. canadensis之间光合面积和光合能力的功能差异加拿大桉树不同入侵程度下群落中的原住民。根据其在被入侵群落中的相对丰度，将加拿大桉树的入侵水平分为以下三种类型：(I) 无入侵，(II) 轻度入侵，(III) 高度入侵。无论入侵程度如何，加拿大桉树的光合能力均显着高于加拿大桉树入侵群落中的本地植物。E. canadensis的光合面积明显低于 E. canadensis 下群落中的本地人入侵与入侵级别无关。光合能力对加拿大桉树生长性能的直接影响和间接影响均明显高于光合面积。因此，在其入侵过程中，加拿大桉树的光合能力对其生长性能可能比光合面积更为关键。