Technical Scheme for Early Warning of Spartina anglica Invasion Dynamics in High-Latitude Estuarine Areas of China Based on UAV Multispectral Remote Sensing

The estuaries in the northern Yellow Sea of China’s high-latitude regions have provided favorable conditions for the natural spread of Spartina anglica (S. anglica) with global warming. However, it is difficult to grasp the occurrence and development process of S. anglica by means of satellite remote sensing and manual on-site monitoring. The S. anglica of three typical river estuaries of Huli River, Yingna River and Zhuanghe River were monitored by unmanned aerial vehicle (UAV) multispectral remote sensing. This approach showed that the population area of S. anglica in the study areas increased year by year from 101,791 m2 in 2021 to 129,755 m2 in 2025, with an overall growth rate of 27.5%. The area proportion of S. anglica at the Huli River estuary has remained stably above 80%, while the Yingna River estuary has the fastest growth rate, with an increase of 90.9% over five years in terms of spatial distribution. It provides a new method for monitoring the dynamics of invasive plants in high-latitude coastal wetlands with UAV multispectral remote sensing in centimeter-level resolution, and accurately identifying early invasion points and their spread trends for early warning and precise control.