Marshes in the Sanjiang Plain, China have decreased by 79.4% (around 2.99 million hectares) since 1954, mainly due to human activities like converting marshes into farmland. Human actions have had a bigger impact (87.86%) on marsh changes compared to natural factors over the last 60 years. This study used various methods to track and analyze the changes in marshes, showing a significant loss of marsh area and increased fragmentation. These findings help us understand wetland changes and can guide better management strategies for wetlands, like wetland restoration.