Abstract: We analyzed the typical landscape types and tidal channel changes of different landscape types in the Yellow River estuary, based on five remote sensing images of Yellow River estuary from 2000 to 2020 and field observation data. The area proportions of bare mudflats, Phragmites australis, and Suaeda salsa decreased, while the landscape fragmentation increased. The area of Spartina alterniflora patches increased by 38.32 km² from 2010 to 2020. The average annual length of tidal channels in different landscape types followed an order of bare mudflats>Spartina alterniflora>Suaeda salsa>Phragmites australis. Average number and density of tidal channels showed as: bare mudflats>Suaeda salsa>Spartina alterniflora>Phragmites australis. From 2000 to 2020, the length of tidal channels in bare mudflats and Suaeda salsa dominated landscape decreased by 15.28 and 14.35 km, respectively, while the length of tidal channels in Spartina alterniflora dominated landscape increased by 86.03 km. The network circuit connectivity, node connectivity, and network connectivity were at a low level. The hydrological connectivity in bare mudflats, Suaeda salsa, and Phragmites australis changed little. There were rapid increases of hydrological connectivity in the Spartina alterniflora dominated landscape from 2015 to 2020.

Key words: Yellow River estuary, coastal wetland, tidal channel, landscape type, distribution character.