Environmental Filtering Drives Plant Community Assembly Processes in the Riparian Marsh of Downstream Yellow River, China

The driver of plant community assembly in riparian marshes is vital but still unclear. In this study, we report the results of sixty plots located along the downstream Yellow River to identify the driver of plant community assemblages. Seven functional traits were measured and compiled to calculate functional beta diversity, and phylogenetic tree was constructed to assess phylogenetic dissimilarity. The analyses show that all of traits had weak phylogenetic signals using the Blomberg's K statistic. The phylogenetic and functional beta diversity present clustering patterns, with the exception of leaf nitrogen concentration and leaf phosphorus concentration; and the standardized effect sizes based on multi-traits, maximum height, leaf dry matter content are well correlated with the environmental gradient. The findings imply that environment filtering was responsible for the variation of beta diversity, and drove community assembly in the riparian marsh. Of all environmental factors, soil salinity is the most crucial indicator to dominate the pattern of beta diversity.