Rapid invasion of Spartina alterniflora in coastal wetlands throughout the world has attracted much attention. Some field and imagery evidence has shown that the landward invasion of S. alterniflora follows the tidal channel networks as the main pathway. However, the specific patterns and processes of its invasion in salt marshes in relation to tidal channel networks are still unclear. Based on yearly satellite images from 2010 to 2018, we studied the patterning relationship between tidal channel networks and the invasion of S. alterniflora at the south bank of the Yellow River Estuary (SBYRE). At the landscape (watershed and cross-watershed) scale, we analyzed the correlation between proxies of tidal channel network drainage efficiency (unchanneled flow lengths (UFL), overmarsh path length (OPL), and tidal channels density (TCD)) and spatial distribution of S. alterniflora. At the local (channel) scale, we examined the area and number of patches of S. alterniflora in different distance buffer zones outward from the tidal channels. Our results showed that, overall, the invasion of S. alterniflora had a strong association with tidal channel networks. Watershed with higher drainage efficiency (smaller OPL) attained larger S. alterniflora area, and higher-order (third-order and above) channels tended to be the main pathway of S. alterniflora invasion. At the local scale, the total area of S. alterniflora in each distance buffer zones increased with distance within 15 m from the tidal channels, whereas the number of patches decreased with distance as expansion stabilized. Overall, the S. alterniflora area within 30 m from the tidal channels remained approximately 14% of its entire distribution throughout the invasion. The results implicated that early control of S. alterniflora invasion should pay close attention to higher-order tidal channels as the main pathway

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互花米草如何与潮汐河道网络一起侵入盐沼？模式和过程

互花米草在世界沿海湿地中的快速入侵引起了广泛关注。一些田野和图像证据表明，互花米草的陆路入侵以潮汐通道网络为主要途径。然而，与潮汐通道网络相关的盐沼入侵的具体模式和过程仍不清楚。基于2010年至2018年的年度卫星图像，我们研究了潮汐通道网络与互花米草的入侵之间的模式关系。在黄河口（SBYRE）的南岸。在景观（集水区和跨集水区）尺度上，我们分析了潮汐河道网络排水效率（无沟流长度（UFL），过沼泽路径长度（OPL）和潮汐河道密度（TCD））的代理与空间分布之间的相关性。的互花米草。在局部（河道）尺度上，我们检查了潮汐河道外不同距离缓冲带中互花米草的面积和数量。我们的结果表明，总体而言，互花米草的入侵与潮汐通道网络密切相关。流域的排水效率更高（OPL较小））获得了更大的互花米草面积，较高阶（三阶及以上）通道往往是互花米草入侵的主要途径。在地方尺度上，每个距离缓冲带中互花米草的总面积在距潮汐道15 m以内的距离处增加，而斑块的数量随着距离的增加而减小。总体而言，在整个入侵过程中，距潮汐通道30 m以内的互花米草面积约占其整个分布的14％。结果提示，早期控制互生链球菌入侵应密切注意高潮汐通道作为主要途径。