Abstract: Large-scale invasion of Spartina alterniflora on coastal wetlands has a great impact on the morphological characteristics of tidal creeks and the succession of plant communities. Based on the remote sensing images from 2008 to 2020, we analyzed the evolution characteristics of S. alterniflora invasion and its effect on the morphological characteristics and plant community distribution of tidal flats in the Yellow River Estuary by using 3S technology, regression analysis, and statistical analysis. The results showed that the area of S. alterniflora had increased rapidly in the Yellow River Estuary since 2008, with a growth rate of 4.47 km²·a^-1. By 2020, the distribution area of S. alterniflora accounted for 26% of the estuary area. With the expansion of S. alterniflora, the areas of Phragmites australis and Suaeda salsa were decreased gradually, with arate of 0.72 and 0.39 km²·a^-1, respectively. In the typical tidal flat area of the Yellow River Estuary, the length and density of tidal creeks were decreased by 8.12 km and 0.24 km·km^-2, respectively. The distribution area of P. australis and S. salsa, as well as the length and density of tidal creeks were significantly negatively correlated with the distribution area of S. alterniflora.

Key words: estuary wetland, Spartina alterniflora, plant community, tidal creeks system, remote sensing.